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<book id="client-api-tutorial">
<title>Programming in Apache Qpid</title>
<subtitle>Cross-Platform AMQP Messaging in Java JMS, .NET, C++, and Python</subtitle>
<chapter>
<title>Introduction</title>
<para>Apache Qpid is a reliable, asynchronous messaging system that
supports the AMQP messaging protocol in several common programming
languages. Qpid is supported on most common platforms.
</para>
<itemizedlist>
<listitem>
<para>
On the Java platform, Qpid uses the
established <ulink url="http://java.sun.com/products/jms/">Java JMS
API</ulink>.
</para>
</listitem>
<listitem>
<para>
For Python, C++, and .NET, Qpid defines its own messaging API, the
<firstterm>Qpid Messaging API</firstterm>, which is
conceptually similar in each.
</para>
<para>
On the .NET platform, Qpid also provides a WCF binding.
</para>
</listitem>
<listitem>
<para>
Ruby will also use the Qpid Messaging API, which will soon
be implemented. (Ruby currently uses an API that is closely
tied to the AMQP version).
</para>
</listitem>
</itemizedlist>
</chapter>
<chapter>
<title>Using the Qpid Messaging API</title>
<para>The Qpid Messaging API is quite simple, consisting of only a
handful of core classes.
</para>
<itemizedlist>
<listitem>
<para>
A <firstterm>message</firstterm> consists of a standard set
of fields (e.g. <literal>subject</literal>,
<literal>reply-to</literal>), an application-defined set of
properties, and message content (the main body of the
message).
</para>
</listitem>
<listitem>
<para>
A <firstterm>connection</firstterm> represents a network
connection to a remote endpoint.
</para>
</listitem>
<listitem>
<para>
A <firstterm>session</firstterm> provides a sequentially
ordered context for sending and receiving
<emphasis>messages</emphasis>. A session is obtained from a
connection.
</para>
</listitem>
<listitem>
<para>
A <firstterm>sender</firstterm> sends messages to a target
using the <literal>sender.send</literal> method. A sender is
obtained from a session for a given target address.
</para>
</listitem>
<listitem>
<para>
A <firstterm>receiver</firstterm> receives messages from a
source using the <literal>receiver.fetch</literal> method.
A receiver is obtained from a session for a given source
address.
</para>
</listitem>
</itemizedlist>
<para>
The following sections show how to use these classes in a
simple messaging program.
</para>
<section>
<title>A Simple Messaging Program in C++</title>
<para>The following C++ program shows how to create a connection,
create a session, send messages using a sender, and receive
messages using a receiver.</para>
<example>
<title>"Hello world!" in C++</title>
<programlisting lang="c++"><![CDATA[
#include <qpid/messaging/Connection.h>
#include <qpid/messaging/Message.h>
#include <qpid/messaging/Receiver.h>
#include <qpid/messaging/Sender.h>
#include <qpid/messaging/Session.h>
#include <iostream>]]>
using namespace qpid::messaging;
int main(int argc, char** argv) {
std::string broker = argc > 1 ? argv[1] : "localhost:5672";
std::string address = argc > 2 ? argv[2] : "amq.topic";
std::string connectionOptions = argc > 3 ? argv[3] : "";
Connection connection(broker, connectionOptions);
try {
connection.open(); <co id="hello-cpp-open" linkends="callout-cpp-open"/>
Session session = connection.createSession(); <co id="hello-cpp-session" linkends="callout-cpp-session"/>
Receiver receiver = session.createReceiver(address); <co id="hello-cpp-receiver" linkends="callout-cpp-receiver"/>
Sender sender = session.createSender(address); <co id="hello-cpp-sender" linkends="callout-cpp-sender"/>
sender.send(Message("Hello world!"));
Message message = receiver.fetch(Duration::SECOND * 1); <co id="hello-cpp-fetch" linkends="callout-cpp-fetch"/>
<![CDATA[std::cout << message.getContent() << std::endl;]]>
session.acknowledge(); <co id="hello-cpp-acknowledge" linkends="callout-cpp-acknowledge"/>
connection.close(); <co id="hello-cpp-close" linkends="callout-cpp-close"/>
return 0;
} catch(const std::exception&amp; error) {
<![CDATA[std::cerr << error.what() << std::endl;]]>
connection.close();
return 1;
}
}</programlisting>
<calloutlist>
<callout id="callout-cpp-open" arearefs="hello-cpp-open">
<para>Establishes the connection with the messaging broker.</para>
</callout>
<callout id="callout-cpp-session" arearefs="hello-cpp-session">
<para>Creates a session object on which messages will be sent and received.</para>
</callout>
<callout id="callout-cpp-receiver" arearefs="hello-cpp-receiver">
<para>Creates a receiver that receives messages from the given address.</para>
</callout>
<callout id="callout-cpp-sender" arearefs="hello-cpp-sender">
<para>Creates a sender that sends to the given address.</para>
</callout>
<callout id="callout-cpp-fetch" arearefs="hello-cpp-fetch">
<para>Receives the next message. The duration is optional, if omitted, will wait indefinitely for the next message.</para>
</callout>
<callout id="callout-cpp-acknowledge" arearefs="hello-cpp-acknowledge">
<para>Acknowledges receipt of all fetched messages on the
session. This informs the broker that the messages were
transferred and processed by the client successfully.</para>
</callout>
<callout id="callout-cpp-close" arearefs="hello-cpp-close">
<para>Closes the connection, all sessions managed by the connection, and all senders and receivers managed by each session.</para>
</callout>
</calloutlist>
</example>
</section>
<section>
<title>A Simple Messaging Program in Python</title>
<para>The following Python program shows how to create a
connection, create a session, send messages using a sender, and
receive messages using a receiver.</para>
<example>
<title>"Hello world!" in Python</title>
<programlisting lang="python"><![CDATA[
import sys
from qpid.messaging import *
broker = "localhost:5672" if len(sys.argv)<2 else sys.argv[1]
address = "amq.topic" if len(sys.argv)<3 else sys.argv[2]]]>
connection = Connection(broker)
try:
connection.open() <co id="hello-python-open" linkends="callout-python-open"/>
session = connection.session() <co id="hello-python-session" linkends="callout-python-session"/>
sender = session.sender(address) <co id="hello-python-sender" linkends="callout-python-sender"/>
receiver = session.receiver(address) <co id="hello-python-receiver" linkends="callout-python-receiver"/>
sender.send(Message("Hello world!"));
message = receiver.fetch(timeout=1) <co id="hello-python-fetch" linkends="callout-python-fetch"/>
print message.content
session.acknowledge() <co id="hello-python-acknowledge" linkends="callout-python-acknowledge"/>
except MessagingError,m:
print m
finally:
connection.close() <co id="hello-python-close" linkends="callout-python-close"/>
</programlisting>
<calloutlist>
<callout id="callout-python-open" arearefs="hello-python-open">
<para>Establishes the connection with the messaging broker.</para>
</callout>
<callout id="callout-python-session" arearefs="hello-python-session">
<para>Creates a session object on which messages will be sent and received.</para>
</callout>
<callout id="callout-python-receiver" arearefs="hello-python-receiver">
<para>Creates a receiver that receives messages from the given address.</para>
</callout>
<callout id="callout-python-sender" arearefs="hello-python-sender">
<para>Creates a sender that sends to the given address.</para>
</callout>
<callout id="callout-python-fetch" arearefs="hello-python-fetch">
<para>Receives the next message. The duration is optional, if omitted, will wait indefinitely for the next message.</para>
</callout>
<callout id="callout-python-acknowledge" arearefs="hello-python-acknowledge">
<para>Acknowledges receipt of all fetched messages on
the session. This informs the broker that the messages were
transfered and processed by the client successfully.</para>
</callout>
<callout id="callout-python-close" arearefs="hello-python-close">
<para>Closes the connection, all sessions managed by the connection, and all senders and receivers managed by each session.</para>
</callout>
</calloutlist>
</example>
</section>
<section>
<title>A Simple Messaging Program in .NET C#</title>
<para>The following .NET C#
<footnote>
<para>
The .NET binding for the Qpid C++ Messaging API
applies to all .NET Framework managed code languages. C# was chosen
for illustration purposes only.
</para>
</footnote>
program shows how to create a connection,
create a session, send messages using a sender, and receive
messages using a receiver.
</para>
<example>
<title>"Hello world!" in .NET C#</title>
<programlisting lang="c++">
using System;
using Org.Apache.Qpid.Messaging; <co id="hello-csharp-using" linkends="callout-csharp-using"/>
namespace Org.Apache.Qpid.Messaging {
class Program {
static void Main(string[] args) {
String broker = args.Length > 0 ? args[0] : "localhost:5672";
String address = args.Length > 1 ? args[1] : "amq.topic";
Connection connection = null;
try {
connection = new Connection(broker);
connection.Open(); <co id="hello-csharp-open" linkends="callout-csharp-open"/>
Session session = connection.CreateSession(); <co id="hello-csharp-session" linkends="callout-csharp-session"/>
Receiver receiver = session.CreateReceiver(address); <co id="hello-csharp-receiver" linkends="callout-csharp-receiver"/>
Sender sender = session.CreateSender(address); <co id="hello-csharp-sender" linkends="callout-csharp-sender"/>
sender.Send(new Message("Hello world!"));
Message message = new Message();
message = receiver.Fetch(DurationConstants.SECOND * 1); <co id="hello-csharp-fetch" linkends="callout-csharp-fetch"/>
Console.WriteLine("{0}", message.GetContent());
session.Acknowledge(); <co id="hello-csharp-acknowledge" linkends="callout-csharp-acknowledge"/>
connection.Close(); <co id="hello-csharp-close" linkends="callout-csharp-close"/>
} catch (Exception e) {
Console.WriteLine("Exception {0}.", e);
if (null != connection)
connection.Close();
}
}
}
}
</programlisting>
<calloutlist>
<callout id="callout-csharp-using" arearefs="hello-csharp-using">
<para> Permits use of Org.Apache.Qpid.Messaging types and methods without explicit namespace qualification. Any .NET project must have a project reference to the assembly file <literal>Org.Apache.Qpid.Messaging.dll</literal> in order to obtain the definitions of the .NET Binding for Qpid Messaging namespace.</para>
</callout>
<callout id="callout-csharp-open" arearefs="hello-csharp-open">
<para>Establishes the connection with the messaging broker.</para>
</callout>
<callout id="callout-csharp-session" arearefs="hello-csharp-session">
<para>Creates a session object on which messages will be sent and received.</para>
</callout>
<callout id="callout-csharp-receiver" arearefs="hello-csharp-receiver">
<para>Creates a receiver that receives messages from the given address.</para>
</callout>
<callout id="callout-csharp-sender" arearefs="hello-csharp-sender">
<para>Creates a sender that sends to the given address.</para>
</callout>
<callout id="callout-csharp-fetch" arearefs="hello-csharp-fetch">
<para>Receives the next message. The duration is optional, if omitted, will wait indefinitely for the next message.</para>
</callout>
<callout id="callout-csharp-acknowledge" arearefs="hello-csharp-acknowledge">
<para>Acknowledges receipt of all fetched messages on the
session. This informs the broker that the messages were
transfered and processed by the client successfully.</para>
</callout>
<callout id="callout-csharp-close" arearefs="hello-csharp-close">
<para>Closes the connection, all sessions managed by the connection, and all senders and receivers managed by each session.</para>
</callout>
</calloutlist>
</example>
</section>
<section id="section-addresses">
<title>Addresses</title>
<para>An <firstterm>address</firstterm> is the name of a message
target or message source.
<footnote><para>In the programs we have just seen, we used
<literal>amq.topic</literal> as the default address if none is
passed in. This is the name of a standard exchange that always
exists on an AMQP 0-10 messaging broker.</para></footnote>
The methods that create senders and receivers require an
address. The details of sending to a particular target or
receiving from a particular source are then handled by the
sender or receiver. A different target or source can be used
simply by using a different address.
</para>
<para>An address resolves to a <firstterm>node</firstterm>. The
Qpid Messaging API recognises two kinds of nodes,
<firstterm>queues</firstterm> and <firstterm>topics</firstterm>
<footnote><para>The terms <emphasis>queue</emphasis> and
<emphasis>topic</emphasis> here were chosen to align with
their meaning in JMS. These two addressing 'patterns',
queue and topic, are sometimes refered as point-to-point
and publish-subscribe. AMQP 0-10 has an exchange type
called a <emphasis>topic exchange</emphasis>. When the term
<emphasis>topic</emphasis> occurs alone, it refers to a
Messaging API topic, not the topic
exchange.</para></footnote>.
A queue stores each message until it has been received and
acknowledged, and only one receiver can receive a given message
<footnote><para>There are exceptions to this rule; for instance,
a receiver can use <literal>browse</literal> mode, which leaves
messages on the queue for other receivers to
read.</para></footnote>.
A topic immediately delivers a message to all eligible
receivers; if there are no eligible receivers, it discards the
message. In the AMQP 0-10 implementation of the API,
<footnote><para>The AMQP 0-10 implementation is the only one
that currently exists.</para></footnote>
queues map to AMQP queues, and topics map to AMQP exchanges.
<footnote><para>In AMQP 0-10, messages are sent to
exchanges, and read from queues. The Messaging API also
allows a sender to send messages to a queue; internally,
Qpid implements this by sending the message to the default
exchange, with the name of the queue as the routing key. The
Messaging API also allows a receiver to receive messages
from a topic; internally, Qpid implements this by setting up
a private subscription queue for the receiver and binding
the subscription queue to the exchange that corresponds to
the topic.</para></footnote>
</para>
<para>In the rest of this tutorial, we present many examples
using two programs that take an address as a command line
parameter. <command>spout</command> sends messages to the
target address, <command>drain</command> receives messages from
the source address. The source code is available in C++, Python, and
.NET C# and can be found in the examples directory for each
language. These programs can use any address string as a source
or a destination, and have many command line options to
configure behavior&mdash;use the <command>-h</command> option
for documentation on these options.
<footnote><para>Currently, the C++, Python, and .NET C#
implementations of <command>drain</command> and
<command>spout</command> have slightly different
options. This tutorial uses the C++ implementation. The
options will be reconciled in the near
future.</para></footnote>
The examples in this tutorial also use the
<command>qpid-config</command> utility to configure AMQP 0-10
queues and exchanges on a Qpid broker.
</para>
<example>
<title>Queues</title>
<para>Create a queue with <command>qpid-config</command>, send a message using
<command>spout</command>, and read it using <command>drain</command>:</para>
<screen>
$ qpid-config add queue hello-world
$ ./spout hello-world
$ ./drain hello-world
Message(properties={spout-id:c877e622-d57b-4df2-bf3e-6014c68da0ea:0}, content='')
</screen>
<para>The queue stored the message sent by <command>spout</command> and delivered
it to <command>drain</command> when requested.</para>
<para>Once the message has been delivered and and acknowledged
by <command>drain</command>, it is no longer available on the queue. If we run
<command>drain</command> one more time, no messages will be retrieved.</para>
<screen>
$ ./drain hello-world
$
</screen>
</example>
<example>
<title>Topics</title>
<para>This example is similar to the previous example, but it
uses a topic instead of a queue.</para>
<para>First, use <command>qpid-config</command> to remove the queue
and create an exchange with the same name:</para>
<screen>
$ qpid-config del queue hello-world
$ qpid-config add exchange topic hello-world
</screen>
<para>Now run <command>drain</command> and <command>spout</command> the same way we did in the previous example:</para>
<screen>
$ ./spout hello-world
$ ./drain hello-world
$
</screen>
<para>Topics deliver messages immediately to any interested
receiver, and do not store messages. Because there were no
receivers at the time <command>spout</command> sent the
message, it was simply discarded. When we ran
<command>drain</command>, there were no messages to
receive.</para>
<para>Now let's run <command>drain</command> first, using the
<literal>-t</literal> option to specify a timeout in seconds.
While <command>drain</command> is waiting for messages,
run <command>spout</command> in another window.</para>
<para><emphasis>First Window:</emphasis></para>
<screen>
$ ./drain -t 30 hello-word
</screen>
<para><emphasis>Second Window:</emphasis></para>
<screen>
$ ./spout hello-word
</screen>
<para>Once <command>spout</command> has sent a message, return
to the first window to see the output from
<command>drain</command>:</para>
<screen>
Message(properties={spout-id:7da2d27d-93e6-4803-8a61-536d87b8d93f:0}, content='')
</screen>
<para>You can run <command>drain</command> in several separate
windows; each creates a subscription for the exchange, and
each receives all messages sent to the exchange.</para>
</example>
<section>
<title>Address Strings</title>
<para>So far, our examples have used address strings that
contain only the name of a node. An <firstterm>address
string</firstterm> can also contain a
<firstterm>subject</firstterm> and
<firstterm>options</firstterm>.</para>
<para>The syntax for an address string is:</para>
<programlisting><![CDATA[
address_string ::= <address> [ / <subject> ] [ ; <options> ]
options ::= { <key> : <value>, ... }
]]></programlisting>
<para>Addresses, subjects, and keys are strings. Values can
be numbers, strings (with optional single or double quotes),
maps, or lists. A complete BNF for address strings appears in
<xref linkend="section-address-string-bnf"/>.</para>
<para>So far, the address strings in this tutorial have only
used simple names. The following sections show how to use
subjects and options.</para>
</section>
<section>
<title>Subjects</title>
<para>Every message has a property called
<firstterm>subject</firstterm>, which is analogous to the
subject on an email message. If no subject is specified, the
message's subject is null. For convenience, address strings
also allow a subject. If a sender's address contains a
subject, it is used as the default subject for the messages
it sends.
If a receiver's address contains a subject, it is used to
select only messages that match the subject&mdash;the matching
algorithm depends on the message source.
</para>
<para>
In AMQP 0-10, each exchange type has its own matching
algorithm. This is discussed in
<xref linkend="section-amqp0-10-mapping"/>.
</para>
<note>
<para>
Currently, a receiver bound to a queue ignores subjects,
receiving messages from the queue without filtering. Support
for subject filtering on queues will be implemented soon.
</para>
</note>
<example>
<title>Using subjects</title>
<para>In this example we show how subjects affect message
flow.</para>
<para>First, let's use <command>qpid-config</command> to create a topic exchange.</para>
<screen>
$ qpid-config add exchange topic news-service
</screen>
<para>Now we use drain to receive messages from <literal>news-service</literal> that match the subject <literal>sports</literal>.</para>
<para><emphasis>First Window:</emphasis></para>
<screen>
$ ./drain -t 30 news-service/sports
</screen>
<para>In a second window, let's send messages to <literal>news-service</literal> using two different subjects:</para>
<para><emphasis>Second Window:</emphasis></para>
<screen>
$ ./spout news-service/sports
$ ./spout news-service/news
</screen>
<para>Now look at the first window, the message with the
subject <literal>sports</literal> has been received, but not
the message with the subject <literal>news</literal>:</para>
<screen>
Message(properties={qpid.subject:sports, spout-id:9441674e-a157-4780-a78e-f7ccea998291:0}, content='')
</screen>
<para>If you run <command>drain</command> in multiple
windows using the same subject, all instances of
<command>drain</command> receive the messages for that
subject.</para>
</example>
<para>The AMQP exchange type we are using here,
<literal>amq.topic</literal>, can also do more sophisticated
matching.
A sender's subject can contain multiple words separated by a
<quote>.</quote> delimiter. For instance, in a news
application, the sender might use subjects like
<literal>usa.news</literal>, <literal>usa.weather</literal>,
<literal>europe.news</literal>, or
<literal>europe.weather</literal>.
The receiver's subject can include wildcard characters&mdash;
<quote>#</quote> matches one or more words in the message's
subject, <quote>*</quote> matches a single word.
For instance, if the subject in the source address is
<literal>*.news</literal>, it matches messages with the
subject <literal>europe.news</literal> or
<literal>usa.news</literal>; if it is
<literal>europe.#</literal>, it matches messages with subjects
like <literal>europe.news</literal> or
<literal>europe.pseudo.news</literal>.</para>
<example>
<title>Subjects with multi-word keys</title>
<para>This example uses drain and spout to demonstrate the
use of subjects with two-word keys.</para>
<para>Let's use <command>drain</command> with the subject
<literal>*.news</literal> to listen for messages in which
the second word of the key is
<literal>news</literal>.</para>
<para><emphasis>First Window:</emphasis></para>
<screen>
$ ./drain -t 30 news-service/*.news
</screen>
<para>Now let's send messages using several different
two-word keys:</para>
<para><emphasis>Second Window:</emphasis></para>
<screen>
$ ./spout news-service/usa.news
$ ./spout news-service/usa.sports
$ ./spout news-service/europe.sports
$ ./spout news-service/europe.news
</screen>
<para>In the first window, the messages with
<literal>news</literal> in the second word of the key have
been received:</para>
<screen>
Message(properties={qpid.subject:usa.news, spout-id:73fc8058-5af6-407c-9166-b49a9076097a:0}, content='')
Message(properties={qpid.subject:europe.news, spout-id:f72815aa-7be4-4944-99fd-c64c9747a876:0}, content='')
</screen>
<para>Next, let's use <command>drain</command> with the
subject <literal>#.news</literal> to match any sequence of
words that ends with <literal>news</literal>.</para>
<para><emphasis>First Window:</emphasis></para>
<screen>
$ ./drain -t 30 news-service/#.news
</screen>
<para>In the second window, let's send messages using a
variety of different multi-word keys:</para>
<para><emphasis>Second Window:</emphasis></para>
<screen>
$ ./spout news-service/news
$ ./spout news-service/sports
$ ./spout news-service/usa.news
$ ./spout news-service/usa.sports
$ ./spout news-service/usa.faux.news
$ ./spout news-service/usa.faux.sports
</screen>
<para>In the first window, messages with
<literal>news</literal> in the last word of the key have been
received:</para>
<screen>
Message(properties={qpid.subject:news, spout-id:cbd42b0f-c87b-4088-8206-26d7627c9640:0}, content='')
Message(properties={qpid.subject:usa.news, spout-id:234a78d7-daeb-4826-90e1-1c6540781eac:0}, content='')
Message(properties={qpid.subject:usa.faux.news, spout-id:6029430a-cfcb-4700-8e9b-cbe4a81fca5f:0}, content='')
</screen>
</example>
</section>
<section>
<title>Address String Options</title>
<para>
The options in an address string can contain additional
information for the senders or receivers created for it,
including:
</para>
<itemizedlist>
<listitem>
<para>
Policies for assertions about the node to which an address
refers.
</para>
<para>
For instance, in the address string <literal>my-queue;
{assert: always, node:{ type: queue }}</literal>, the node
named <literal>my-queue</literal> must be a queue; if not,
the address does not resolve to a node, and an exception
is raised.
</para>
</listitem>
<listitem>
<para>
Policies for automatically creating or deleting the node to which an address refers.
</para>
<para>
For instance, in the address string <literal>xoxox ; {create: always}</literal>,
the queue <literal>xoxox</literal> is created, if it does
not exist, before the address is resolved.
</para>
</listitem>
<listitem>
<para>
Extension points that can be used for sender/receiver configuration.
</para>
<para>
For instance, if the address for a receiver is
<literal>my-queue; {mode: browse}</literal>, the receiver
works in <literal>browse</literal> mode, leaving messages
on the queue so other receivers can receive them.
</para>
</listitem>
<listitem>
<para>
Extension points providing more direct control over the underlying protocol.
</para>
<para>
For instance, the <literal>x-bindings</literal> property
allows greater control over the AMQP 0-10 binding process
when an address is resolved.
</para>
</listitem>
</itemizedlist>
<para>
Let's use some examples to show how these different kinds of
address string options affect the behavior of senders and
receives.
</para>
<section>
<title>assert</title>
<para>
In this section, we use the <literal>assert</literal> option
to ensure that the address resolves to a node of the required
type.
</para>
<example>
<title>Assertions on Nodes</title>
<para>Let's use <command>qpid-config</command> to create a
queue and a topic.</para>
<screen>
$ qpid-config add queue my-queue
$ qpid-config add exchange topic my-topic
</screen>
<para>
We can now use the address specified to drain to assert that it is
of a particular type:
</para>
<screen>
$ ./drain 'my-queue; {assert: always, node:{ type: queue }}'
$ ./drain 'my-queue; {assert: always, node:{ type: topic }}'
2010-04-20 17:30:46 warning Exception received from broker: not-found: not-found: Exchange not found: my-queue (../../src/qpid/broker/ExchangeRegistry.cpp:92) [caused by 2 \x07:\x01]
Exchange my-queue does not exist
</screen>
<para>
The first attempt passed without error as my-queue is indeed a
queue. The second attempt however failed; my-queue is not a
topic.
</para>
<para>
We can do the same thing for my-topic:
</para>
<screen>
$ ./drain 'my-topic; {assert: always, node:{ type: topic }}'
$ ./drain 'my-topic; {assert: always, node:{ type: queue }}'
2010-04-20 17:31:01 warning Exception received from broker: not-found: not-found: Queue not found: my-topic (../../src/qpid/broker/SessionAdapter.cpp:754) [caused by 1 \x08:\x01]
Queue my-topic does not exist
</screen>
</example>
<para>Now let's use the <literal>create</literal> option to
create the queue <literal>xoxox</literal> if it does not already
exist:</para>
</section>
<section>
<title>create</title>
<para>In previous examples, we created the queue before
listening for messages on it. Using <literal>create:
always</literal>, the queue is automatically created if it
does not exist.</para>
<example>
<title>Creating a Queue Automatically</title>
<para><emphasis>First Window:</emphasis></para>
<screen>$ ./drain -t 30 "xoxox ; {create: always}"</screen>
<para>Now we can send messages to this queue:</para>
<para><emphasis>Second Window:</emphasis></para>
<screen>$ ./spout "xoxox ; {create: always}"</screen>
<para>Returning to the first window, we see that <command>drain</command> has received this message:</para>
<screen>Message(properties={spout-id:1a1a3842-1a8b-4f88-8940-b4096e615a7d:0}, content='')</screen>
</example>
<para>The details of the node thus created can be controlled by further options within the node. See <xref linkend="table-node-properties"/> for details.</para>
</section>
<section>
<title>browse</title>
<para>Some options specify message transfer semantics; for
instance, they may state whether messages should be consumed or
read in browsing mode, or specify reliability
characteristics. The following example uses the
<literal>browse</literal> option to receive messages without
removing them from a queue.</para>
<example>
<title>Browsing a Queue</title>
<para>
Let's use the browse mode to receive messages without
removing them from the queue. First we send three messages to the
queue:
</para>
<screen>
$ ./spout my-queue --content one
$ ./spout my-queue --content two
$ ./spout my-queue --content three
</screen>
<para>Now we use drain to get those messages, using the browse option:</para>
<screen>
$ ./drain 'my-queue; {mode: browse}'
Message(properties={spout-id:fbb93f30-0e82-4b6d-8c1d-be60eb132530:0}, content='one')
Message(properties={spout-id:ab9e7c31-19b0-4455-8976-34abe83edc5f:0}, content='two')
Message(properties={spout-id:ea75d64d-ea37-47f9-96a9-d38e01c97925:0}, content='three')
</screen>
<para>We can confirm the messages are still on the queue by repeating the drain:</para>
<screen>
$ ./drain 'my-queue; {mode: browse}'
Message(properties={spout-id:fbb93f30-0e82-4b6d-8c1d-be60eb132530:0}, content='one')
Message(properties={spout-id:ab9e7c31-19b0-4455-8976-34abe83edc5f:0}, content='two')
Message(properties={spout-id:ea75d64d-ea37-47f9-96a9-d38e01c97925:0}, content='three')
</screen>
</example>
</section>
<section>
<title>x-bindings</title>
<para>Greater control over the AMQP 0-10 binding process can
be achieved by including an <literal>x-bindings</literal>
option in an address string.
For instance, the XML Exchange is an AMQP 0-10 custom exchange
provided by the Apache Qpid C++ broker. It allows messages to
be filtered using XQuery; queries can address either message
properties or XML content in the body of the message. The
xquery is specified in the arguments field of the AMQP 0-10
command. When using the messaging API an xquery can be
specified in and address that resolves to an XML exchange by
using the x-bindings property.</para>
<para>An instance of the XML Exchange must be added before it
can be used:</para>
<programlisting>
$ qpid-config add exchange xml xml
</programlisting>
<para>When using the XML Exchange, a receiver provides an
XQuery as an x-binding argument. If the query contains a
context item (a path starting with <quote>.</quote>), then it
is applied to the content of the message, which must be
well-formed XML. For instance, <literal>./weather</literal> is
a valid XQuery, which matches any message in which the root
element is named <literal>weather</literal>. Here is an
address string that contains this query:</para>
<programlisting><![CDATA[
xml; {
link: {
x-bindings: [{exchange:xml, key:weather, arguments:{xquery:"./weather"} }]
}
}
]]></programlisting>
<para>When using longer queries with <command>drain</command>,
it is often useful to place the query in a file, and use
<command>cat</command> in the command line. We do this in the
following example.</para>
<example>
<title>Using the XML Exchange</title>
<para>This example uses an x-binding that contains queries, which filter based on the content of XML messages. Here is an XQuery that we will use in this example:</para>
<programlisting>
<![CDATA[
let $w := ./weather
return $w/station = 'Raleigh-Durham International Airport (KRDU)'
and $w/temperature_f > 50
and $w/temperature_f - $w/dewpoint > 5
and $w/wind_speed_mph > 7
and $w/wind_speed_mph < 20 ]]>
</programlisting>
<para>We can specify this query in an x-binding to listen to messages that meet the criteria specified by the query:</para>
<para><emphasis>First Window:</emphasis></para>
<screen>
$ ./drain -f "xml; {link:{x-bindings:[{key:'weather',
arguments:{xquery:\"$(cat rdu.xquery )\"}}]}}"
</screen>
<para>In another window, let's create an XML message that meets the criteria in the query, and place it in the file <filename>rdu.xml</filename>:</para>
<programlisting>
<![CDATA[
<weather>
<station>Raleigh-Durham International Airport (KRDU)</station>
<wind_speed_mph>16</wind_speed_mph>
<temperature_f>70</temperature_f>
<dewpoint>35</dewpoint>
</weather>
]]></programlisting>
<para>Now let's use <command>spout</command> to send this message to the XML exchange:</para>
<para><emphasis>Second Window:</emphasis></para>
<screen>
spout --content "$(cat rdu.xml)" xml/weather
</screen>
<para>Returning to the first window, we see that the message has been received:</para>
<screen><![CDATA[$ ./drain -f "xml; {link:{x-bindings:[{exchange:'xml', key:'weather', arguments:{xquery:\"$(cat rdu.xquery )\"}}]}}"
Message(properties={qpid.subject:weather, spout-id:31c431de-593f-4bec-a3dd-29717bd945d3:0},
content='<weather>
<station>Raleigh-Durham International Airport (KRDU)</station>
<wind_speed_mph>16</wind_speed_mph>
<temperature_f>40</temperature_f>
<dewpoint>35</dewpoint>
</weather>') ]]>
</screen>
</example>
</section>
<!--
<para>When sending data using <command>cat</command> to provide arguments to <command>spout</command>, you can use <command>sed</command> to change the values that are sent:</para>
<screen>
spout - -content "$(cat rdu.xml | sed -e 's/70/45/')" xml/weather
</screen>
-->
<!--
TODO: Add some reliability option examples
-->
<section>
<title>Address String Options - Reference</title>
<table pgwide="1">
<title>Address String Options</title>
<tgroup cols="3">
<thead>
<colspec colnum="1" colwidth="1*"/>
<colspec colnum="2" colwidth="3*"/>
<colspec colnum="3" colwidth="3*"/>
<row>
<entry>option</entry>
<entry>value</entry>
<entry>semantics</entry>
</row>
</thead>
<tbody>
<row>
<entry>
assert
</entry>
<entry>
one of: always, never, sender or receiver
</entry>
<entry>
Asserts that the properties specified in the node option
match whatever the address resolves to. If they do not,
resolution fails and an exception is raised. <!-- ###
Which exception -->
</entry>
</row>
<row>
<entry>
create
</entry>
<entry>
one of: always, never, sender or receiver
</entry>
<entry>
Creates the node to which an address refers if it does
not exist. No error is raised if the node does
exist. The details of the node may be specified in the
node option.
</entry>
</row>
<row>
<entry>
delete
</entry>
<entry>
one of: always, never, sender or receiver
</entry>
<entry>
Delete the node when the sender or receiver is closed.
</entry>
</row>
<row>
<entry>
node
</entry>
<entry>
A nested map containing the entries shown in <xref linkend="table-node-properties"/>.
</entry>
<entry>
Specifies properties of the node to which the address
refers. These are used in conjunction with the assert or
create options.
</entry>
</row>
<row>
<entry>
link
</entry>
<entry>
A nested map containing the entries shown in <xref linkend="table-link-properties"/>.
</entry>
<entry>
Used to control the establishment of a conceptual link
from the client application to or from the target/source
address.
</entry>
</row>
<row>
<entry>
mode
</entry>
<entry>
one of: browse, consume
</entry>
<entry>
This option is only of relevance for source addresses
that resolve to a queue. If browse is specified the
messages delivered to the receiver are left on the queue
rather than being removed. If consume is specified the
normal behaviour applies; messages are removed from the
queue once the client acknowledges their receipt.
</entry>
</row>
</tbody>
</tgroup>
</table>
<table id="table-node-properties" pgwide="1">
<title>Node Properties</title>
<tgroup cols="3">
<thead>
<colspec colnum="1" colwidth="1*"/>
<colspec colnum="2" colwidth="3*"/>
<colspec colnum="3" colwidth="3*"/>
<row>
<entry>property</entry>
<entry>value</entry>
<entry>semantics</entry>
</row>
</thead>
<tbody>
<row>
<entry>
type
</entry>
<entry>
topic, queue
</entry>
<entry>
Indicates the type of the node.
</entry>
</row>
<row>
<entry>
durable
</entry>
<entry>
True, False
</entry>
<entry>
Indicates whether the node survives a loss of
volatile storage e.g. if the broker is restarted.
</entry>
</row>
<row>
<entry>
x-declare
</entry>
<entry>
A nested map whose values correspond to the valid fields
on an AMQP 0-10 queue-declare or exchange-declare
command.
</entry>
<entry>
These values are used to fine tune the creation or
assertion process. Note however that they are protocol
specific.
</entry>
</row>
<row>
<entry>
x-bindings
</entry>
<entry>
A nested list in which each binding is represented by
a map. The entries of the map for a binding contain
the fields that describe an AMQP 0-10 binding. Here is
the format for x-bindings:
<programlisting><![CDATA[
[
{
exchange: <exchange>,
queue: <queue>,
key: <key>,
arguments: {
<key_1>: <value_1>,
...,
<key_n>: <value_n> }
},
...
]
]]></programlisting>
</entry>
<entry>
In conjunction with the create option, each of these
bindings is established as the address is resolved. In
conjunction with the assert option, the existence of
each of these bindings is verified during
resolution. Again, these are protocol specific.
</entry>
</row>
</tbody>
</tgroup>
</table>
<table id="table-link-properties" pgwide="1">
<title>Link Properties</title>
<tgroup cols="3">
<thead>
<colspec colnum="1" colwidth="1*"/>
<colspec colnum="2" colwidth="3*"/>
<colspec colnum="3" colwidth="3*"/>
<row>
<entry>option</entry>
<entry>value</entry>
<entry>semantics</entry>
</row>
</thead>
<tbody>
<row>
<entry>
reliability
</entry>
<entry>
one of: unreliable, at-least-once, at-most-once, exactly-once
</entry>
<entry>
Reliability indicates the level of reliability that
the sender or receiver. <literal>unreliable</literal>
and <literal>at-most-once</literal> are currently
treated as synonyms, and allow messages to be lost if
a broker crashes or the connection to a broker is
lost. <literal>at-least-once</literal> guarantees that
a message is not lost, but duplicates may be
received. <literal>exactly-once</literal> guarantees
that a message is not lost, and is delivered precisely
once. Currently only <literal>unreliable</literal>
and <literal>at-least-once</literal> are supported.
<footnote><para>If at-most-once is requested,
unreliable will be used and for durable messages on
durable queues there is the possibility that messages
will be redelivered; if exactly-once is requested,
at-most-once will be used and the application needs to
be able to deal with duplicates.</para></footnote>
</entry>
</row>
<row>
<entry>
durable
</entry>
<entry>
True, False
</entry>
<entry>
Indicates whether the link survives a loss of
volatile storage e.g. if the broker is restarted.
</entry>
</row>
<row>
<entry>
x-declare
</entry>
<entry>
A nested map whose values correspond to the valid fields
of an AMQP 0-10 queue-declare command.
</entry>
<entry>
These values can be used to customise the subscription
queue in the case of receiving from an exchange. Note
however that they are protocol specific.
</entry>
</row>
<row>
<entry>
x-subscribe
</entry>
<entry>
A nested map whose values correspond to the valid fields
of an AMQP 0-10 message-subscribe command.
</entry>
<entry>
These values can be used to customise the subscription.
</entry>
</row>
<row>
<entry>
x-bindings
</entry>
<entry>
A nested list each of whose entries is a map that may
contain fields (queue, exchange, key and arguments)
describing an AMQP 0-10 binding.
</entry>
<entry>
These bindings are established during resolution
independent of the create option. They are considered
logically part of the linking process rather than of
node creation.
</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
</section>
<section id="section-address-string-bnf">
<title>Address String Grammar</title>
<para>This section provides a formal grammar for address strings.</para>
<formalpara>
<title>Tokens</title>
<para>The following regular expressions define the tokens used
to parse address strings:</para></formalpara>
<programlisting><![CDATA[
LBRACE: \\{
RBRACE: \\}
LBRACK: \\[
RBRACK: \\]
COLON: :
SEMI: ;
SLASH: /
COMMA: ,
NUMBER: [+-]?[0-9]*\\.?[0-9]+
ID: [a-zA-Z_](?:[a-zA-Z0-9_-]*[a-zA-Z0-9_])?
STRING: "(?:[^\\\\"]|\\\\.)*"|\'(?:[^\\\\\']|\\\\.)*\'
ESC: \\\\[^ux]|\\\\x[0-9a-fA-F][0-9a-fA-F]|\\\\u[0-9a-fA-F][0-9a-fA-F][0-9a-fA-F][0-9a-fA-F]
SYM: [.#*%@$^!+-]
WSPACE: [ \\n\\r\\t]+
]]></programlisting>
<formalpara>
<title>Grammar</title>
<para>The formal grammar for addresses is given below:</para>
</formalpara>
<programlisting><![CDATA[
address := name [ SLASH subject ] [ ";" options ]
name := ( part | quoted )+
subject := ( part | quoted | SLASH )*
quoted := STRING / ESC
part := LBRACE / RBRACE / COLON / COMMA / NUMBER / ID / SYM
options := map
map := "{" ( keyval ( "," keyval )* )? "}"
keyval "= ID ":" value
value := NUMBER / STRING / ID / map / list
list := "[" ( value ( "," value )* )? "]"
]]></programlisting>
<formalpara>
<title>Address String Options</title>
<para>The address string options map supports the following parameters:</para>
</formalpara>
<programlisting><![CDATA[
<name> [ / <subject> ] ; {
create: always | sender | receiver | never,
delete: always | sender | receiver | never,
assert: always | sender | receiver | never,
mode: browse | consume,
node: {
type: queue | topic,
durable: True | False,
x-declare: { ... <declare-overrides> ... },
x-bindings: [<binding_1>, ... <binding_n>]
},
link: {
name: <link-name>,
durable: True | False,
reliability: unreliable | at-most-once | at-least-once | exactly-once,
x-declare: { ... <declare-overrides> ... },
x-bindings: [<binding_1>, ... <binding_n>],
x-subscribe: { ... <subscribe-overrides> ... }
}
}
]]></programlisting>
<itemizedlist>
<title>Create, Delete, and Assert Policies</title>
<para>The create, delete, and assert policies specify who should
perfom the associated action:</para>
<listitem><para><emphasis>always</emphasis>: the action is performed by any messaging client</para></listitem>
<listitem><para><emphasis>sender</emphasis>: the action is only performed by a sender</para></listitem>
<listitem><para><emphasis>receiver</emphasis>: the action is only performed by a receiver</para></listitem>
<listitem><para><emphasis>never</emphasis>: the action is never performed (this is the default)</para></listitem>
</itemizedlist>
<itemizedlist>
<title>Node-Type</title>
<para>The node-type is one of:</para>
<listitem><para><emphasis>topic</emphasis>: in the AMQP 0-10
mapping, a topic node defaults to the topic exchange, x-declare
may be used to specify other exchange types</para></listitem>
<listitem><para><emphasis>queue</emphasis>: this is the default node-type</para></listitem>
</itemizedlist>
</section>
</section>
<section id="replay">
<title>Sender Capacity and Replay</title>
<para>The send method of a sender has an optional second parameter
that controls whether the send call is synchronous or not. A
synchronous send call will block until the broker has confirmed
receipt of the message. An asynchronous send call will return
before the broker confirms receipt of the message, allowing for
example further send calls to be made without waiting for a
roundtrip to the broker for each message. This is desirable where
increased throughput is important.</para>
<para>The sender maintains a list of sent messages whose receipt
has yet to be confirmed by the broker. The maximum number of such
messages that it will hold is defined by the capacity of the
sender, which can be set by the application. If an application
tries to send with a sender whose capacity is already fully used
up, the send call will block waiting for capacity regardless of
the value of the sync flag.</para>
<para>The sender can be queried for the available space (i.e. the
unused capacity), and for the current count of unsettled messages
(i.e. those held in the replay list pending confirmation by the
server). When the unsettled count is zero, all messages on that
sender have been successfully sent.</para>
<para>If the connection fails and is transparently reconnected
(see <xref linkend="connection-options"/> for details on how to control
this feature), the unsettled messages for each sender over that
connection will be re-transmitted. This provides a transparent
level of reliability. This feature can be controlled through the
link's reliability as defined in the address (see
<xref linkend="table-link-properties"/>). At present only
at-least-once guarantees are offered. </para>
</section>
<section id="prefetch">
<title>Receiver Capacity (Prefetch)</title>
<para>By default, a receiver requests the next message from the
server in response to each fetch call, resulting in messages being
sent to the receiver one at a time. As in the case of sending, it
is often desirable to avoid this roundtrip for each message. This
can be achieved by allowing the receiver
to <firstterm>prefetch</firstterm> messages in anticipation of
fetch calls being made. The receiver needs to be able to store
these prefetched messages, the number it can hold is controlled by
the receivers capacity.</para>
</section>
<section id="acknowledgements">
<title>Acknowledging Received Messages</title>
<para>Applications that receive messages should acknowledge their
receipt by calling the session's acknowledge method. As in the
case of sending messages, acknowledged transfer of messages to
receivers provides at-least-once reliability, which means that the
loss of the connection or a client crash does not result in lost
messages; durable messages are not lost even if the broker is
restarted.
Some cases may not require this however and the reliability can be
controlled through a link property in the address options (see
<xref linkend="table-link-properties"/>).</para>
<para>The acknowledge call acknowledges all messages received on
the session (i.e. all message that have been returned from a fetch
call on a receiver created on that session).</para>
<para>The acknowledge call also support an optional parameter
controlling whether the call is synchronous or not. A synchronous
acknowledge will block until the server has confirmed that it has
received the acknowledgement. In the asynchronous case, when the
call returns there is not yet any guarantee that the server has
received and processed the acknowledgement. The session may be
queried for the number of unsettled acknowledgements; when that
count is zero all acknowledgements made for received messages have
been successful.</para>
</section>
<section>
<title>Receiving Messages from Multiple Sources</title>
<para>A receiver can only read from one source, but many
programs need to be able to read messages from many sources. In
the Qpid Messaging API, a program can ask a session for
the <quote>next receiver</quote>; that is, the receiver that is
responsible for the next available message. The following
examples show how this is done in C++, Python, and .NET C#.
</para>
<para>Note that to use this pattern you must enable prefetching
for each receiver of interest so that the broker will send
messages before a fetch call is made. See
<xref linkend="prefetch"/> for more on this.</para>
<example>
<title>Receiving Messages from Multiple Sources</title>
<para>C++:</para>
<programlisting><![CDATA[
Receiver receiver1 = session.createReceiver(address1);
receiver1.setCapacity(10);
Receiver receiver2 = session.createReceiver(address2);
receiver2.setCapacity(10);
Message message = session.nextReceiver().fetch();
std::cout << message.getContent() << std::endl;
session.acknowledge(); // acknowledge message receipt
]]> </programlisting>
<para>Python:</para>
<programlisting><![CDATA[
receiver1 = session.receiver(address1)
receiver1.capacity = 10
receiver2 = session.receiver(address)
receiver2.capacity = 10
message = session.next_receiver().fetch()
print message.content
session.acknowledge()
]]> </programlisting>
<para>.NET C#:</para>
<programlisting><![CDATA[
Receiver receiver1 = session.CreateReceiver(address1);
receiver1.Capacity = 10;
Receiver receiver2 = session.CreateReceiver(address2);
receiver2.Capacity = 10;
Message message = new Message();
message = session.NextReceiver().Fetch();
Console.WriteLine("{0}", message.GetContent());
session.Acknowledge();
]]> </programlisting>
</example>
</section>
<section>
<title>Transactions</title>
<para>Sometimes it is useful to be able to group messages
transfers - sent and/or received - on a session into atomic
grouping. This can be done be creating the session as
transactional. On a transactional session sent messages only
become available at the target address on commit. Likewise any
received and acknowledged messages are only discarded at their
source on commit
<footnote><para>Note that this currently is only true for
messages received using a reliable mode
e.g. at-least-once. Messages sent by a broker to a receiver in
unreliable receiver will be discarded immediately regardless of
transctionality.</para></footnote>
.</para>
<example>
<title>Transactions</title>
<para>C++:</para>
<programlisting><![CDATA[
Connection connection(broker);
Session session = connection.createTransactionalSession();
...
if (smellsOk())
session.commit();
else
session.rollback();
]]></programlisting>
<para>
.NET C#:
</para>
<programlisting>
Connection connection = new Connection(broker);
Session session = connection.CreateTransactionalSession();
...
if (smellsOk())
session.Commit();
else
session.Rollback();
</programlisting>
<!--
<para>Python</para>
<programlisting><![CDATA[
### TODO
]]></programlisting>
-->
</example>
</section>
<section id="connection-options">
<title>Connection Options</title>
<para>
Aspects of the connections behaviour can be controlled through
specifying connection options. For example, connections can be
configured to automatically reconnect if the connection to a
broker is lost.
</para>
<example>
<title>Specifying Connection Options in C++, Python, and .NET</title>
<para>In C++, these options can be set using <function>Connection::setOption()</function> or by passing in a set of options to the constructor. The options can be passed in as a map or in string form:</para>
<programlisting><![CDATA[
Connection connection("localhost:5672", "{reconnect: true}");
try {
connection.open();
!!! SNIP !!!
]]></programlisting>
<para>or</para>
<programlisting><![CDATA[
Connection connection("localhost:5672");
connection.setOption("reconnect", true);
try {
connection.open();
!!! SNIP !!!
]]></programlisting>
<para>In Python, these options can be set as attributes of the connection or using named arguments in
the <function>Connection</function> constructor:</para>
<programlisting><![CDATA[
connection = Connection("localhost:5672", reconnect=True)
try:
connection.open()
!!! SNIP !!!
]]></programlisting>
<para>or</para>
<programlisting><![CDATA[
connection = Connection("localhost:5672")
connection.reconnect = True
try:
connection.open()
!!! SNIP !!!
]]></programlisting>
<para>
In .NET, these options can be set using <function>Connection.SetOption()</function> or by passing in a set of options to the constructor. The options can be passed in as a map or in string form:
</para>
<programlisting>
Connection connection= new Connection(&#34;localhost:5672&#34;, &#34;{reconnect: true}&#34;);
try {
connection.Open();
!!! SNIP !!!
</programlisting>
<para>
or
</para>
<programlisting>
Connection connection = new Connection(&#34;localhost:5672&#34;);
connection.SetOption(&#34;reconnect&#34;, true);
try {
connection.Open();
!!! SNIP !!!
</programlisting>
<para>See the reference documentation for details in each language.</para>
</example>
<para>The following table lists the supported connection options.</para>
<table pgwide="1">
<title>Connection Options</title>
<tgroup cols="3">
<thead>
<colspec colnum="1" colwidth="1*"/>
<colspec colnum="2" colwidth="1*"/>
<colspec colnum="3" colwidth="3*"/>
<row>
<entry>option name</entry>
<entry>value type</entry>
<entry>semantics</entry>
</row>
</thead>
<tbody>
<row>
<entry>
<literal>username</literal>
</entry>
<entry>
string
</entry>
<entry>
The username to use when authenticating to the broker.
</entry>
</row>
<row>
<entry>
<literal>password</literal>
</entry>
<entry>
string
</entry>
<entry>
The password to use when authenticating to the broker.
</entry>
</row>
<row>
<entry>
<literal>sasl_mechanisms</literal>
</entry>
<entry>
string
</entry>
<entry>
The specific SASL mechanisms to use with the python
client when authenticating to the broker. The value
is a space separated list.
</entry>
</row>
<row>
<entry>
<literal>reconnect</literal>
</entry>
<entry>
boolean
</entry>
<entry>
Transparently reconnect if the connection is lost.
</entry>
</row>
<row>
<entry>
<literal>reconnect_timeout</literal>
</entry>
<entry>
integer
</entry>
<entry>
Total number of seconds to continue reconnection attempts before giving up and raising an exception.
</entry>
</row>
<row>
<entry>
<literal>reconnect_limit</literal>
</entry>
<entry>
integer
</entry>
<entry>
Maximum number of reconnection attempts before giving up and raising an exception.
</entry>
</row>
<row>
<entry>
<literal>reconnect_interval_min</literal>
</entry>
<entry>
integer representing time in seconds
</entry>
<entry>
Minimum number of seconds between reconnection attempts. The first reconnection attempt is made immediately; if that fails, the first reconnection delay is set to the value of <literal>reconnect_interval_min</literal>; if that attempt fails, the reconnect interval increases exponentially until a reconnection attempt succeeds or <literal>reconnect_interval_max</literal> is reached.
</entry>
</row>
<row>
<entry>
<literal>reconnect_interval_max</literal>
</entry>
<entry>
integer representing time in seconds
</entry>
<entry>
Maximum reconnect interval.
</entry>
</row>
<row>
<entry>
<literal>reconnect_interval</literal>
</entry>
<entry>
integer representing time in seconds
</entry>
<entry>
Sets both <literal>reconnection_interval_min</literal> and <literal>reconnection_interval_max</literal> to the same value.
</entry>
</row>
<row>
<entry>
<literal>heartbeat</literal>
</entry>
<entry>
integer representing time in seconds
</entry>
<entry>
Requests that heartbeats be sent every N seconds. If two
successive heartbeats are missed the connection is
considered to be lost.
</entry>
</row>
<row>
<entry>
<literal>protocol</literal>
</entry>
<entry>
string
</entry>
<entry>
Sets the underlying protocol used. The default option is 'tcp'. To enable ssl, set to 'ssl'. The C++ client additionally supports 'rdma'.
</entry>
</row>
<row>
<entry>
<literal>tcp-nodelay</literal>
</entry>
<entry>
boolean
</entry>
<entry>
Set tcp no-delay, i.e. disable Nagle algorithm. [C++ only]
</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section id="section-Maps">
<title>Maps and Lists in Message Content</title>
<para>Many messaging applications need to exchange data across
languages and platforms, using the native datatypes of each
programming language.</para>
<para>The Qpid Messaging API supports <classname>map</classname> and <classname>list</classname> in message content.
<footnote><para>Unlike JMS, there is not a specific message type for
map messages.</para></footnote>
<footnote>
<para>
Note that the Qpid JMS client supports MapMessages whose values can be nested maps or lists. This is not standard JMS behaviour.
</para>
</footnote>
Specific language support for <classname>map</classname> and <classname>list</classname> objects are shown in the following table.
</para>
<table id="tabl-Programming_in_Apache_Qpid-Qpid_Maps_in_Message_Content">
<title>Map and List Representation in Supported Languages</title>
<tgroup cols="3">
<thead>
<row>
<entry>Language</entry>
<entry>map</entry>
<entry>list</entry>
</row>
</thead>
<tbody>
<row>
<entry>Python</entry>
<entry><classname>dict</classname></entry>
<entry><classname>list</classname></entry>
</row>
<row>
<entry>C++</entry>
<entry><classname>Variant::Map</classname></entry>
<entry><classname>Variant::List</classname></entry>
</row>
<row>
<entry>Java</entry>
<entry><classname>MapMessage</classname></entry>
<entry><classname>&nbsp;</classname></entry>
</row>
<row>
<entry>.NET</entry>
<entry><classname>Dictionary&#60;string, object&#62;</classname></entry>
<entry><classname>Collection&#60;object&#62;</classname></entry>
</row>
</tbody>
</tgroup>
</table>
<para>
In all languages, messages are encoded using AMQP&#39;s portable datatypes.
</para>
<tip>
<para>Because of the differences in type systems among
languages, the simplest way to provide portable messages is to
rely on maps, lists, strings, 64 bit signed integers, and
doubles for messages that need to be exchanged across languages
and platforms.</para>
</tip>
<section id="section-Python-Maps">
<title>Qpid Maps and Lists in Python</title>
<para>In Python, Qpid supports the <classname>dict</classname> and <classname>list</classname> types directly in message content. The following code shows how to send these structures in a message:</para>
<example>
<title>Sending Qpid Maps and Lists in Python</title>
<programlisting><![CDATA[
from qpid.messaging import *
# !!! SNIP !!!
content = {'Id' : 987654321, 'name' : 'Widget', 'percent' : 0.99}
content['colours'] = ['red', 'green', 'white']
content['dimensions'] = {'length' : 10.2, 'width' : 5.1,'depth' : 2.0};
content['parts'] = [ [1,2,5], [8,2,5] ]
content['specs'] = {'colors' : content['colours'],
'dimensions' : content['dimensions'],
'parts' : content['parts'] }
message = Message(content=content)
sender.send(message)
]]> </programlisting>
</example>
<para>The following table shows the datatypes that can be sent in a Python map message,
and the corresponding datatypes that will be received by clients in Java or C++.</para>
<table id="table-Python-Maps" >
<title>Python Datatypes in Maps</title>
<tgroup cols="3">
<thead>
<row>
<entry>Python Datatype</entry>
<entry>&rarr; C++</entry>
<entry>&rarr; Java</entry>
</row>
</thead>
<tbody>
<row><entry>bool</entry><entry>bool</entry><entry>boolean</entry></row>
<row><entry>int</entry><entry>int64</entry><entry>long</entry></row>
<row><entry>long</entry><entry>int64</entry><entry>long</entry></row>
<row><entry>float</entry><entry>double</entry><entry>double</entry></row>
<row><entry>unicode</entry><entry>string</entry><entry>java.lang.String</entry></row>
<row><entry>uuid</entry><entry>qpid::types::Uuid</entry><entry>java.util.UUID</entry></row>
<row><entry>dict</entry><entry>Variant::Map</entry><entry>java.util.Map</entry></row>
<row><entry>list</entry><entry>Variant::List</entry><entry>java.util.List</entry></row>
</tbody>
</tgroup>
</table>
</section>
<section id="section-cpp-Maps">
<title>Qpid Maps and Lists in C++</title>
<para>In C++, Qpid defines the the
<classname>Variant::Map</classname> and
<classname>Variant::List</classname> types, which can be
encoded into message content. The following code shows how to
send these structures in a message:</para>
<example>
<title>Sending Qpid Maps and Lists in C++</title>
<programlisting><![CDATA[
using namespace qpid::types;
// !!! SNIP !!!
Message message;
Variant::Map content;
content["id"] = 987654321;
content["name"] = "Widget";
content["percent"] = 0.99;
Variant::List colours;
colours.push_back(Variant("red"));
colours.push_back(Variant("green"));
colours.push_back(Variant("white"));
content["colours"] = colours;
Variant::Map dimensions;
dimensions["length"] = 10.2;
dimensions["width"] = 5.1;
dimensions["depth"] = 2.0;
content["dimensions"]= dimensions;
Variant::List part1;
part1.push_back(Variant(1));
part1.push_back(Variant(2));
part1.push_back(Variant(5));
Variant::List part2;
part2.push_back(Variant(8));
part2.push_back(Variant(2));
part2.push_back(Variant(5));
Variant::List parts;
parts.push_back(part1);
parts.push_back(part2);
content["parts"]= parts;
Variant::Map specs;
specs["colours"] = colours;
specs["dimensions"] = dimensions;
specs["parts"] = parts;
content["specs"] = specs;
encode(content, message);
sender.send(message, true);
]]> </programlisting>
</example>
<para>The following table shows the datatypes that can be sent
in a C++ map message, and the corresponding datatypes that
will be received by clients in Java and Python.</para>
<table id="table-cpp-Maps">
<title>C++ Datatypes in Maps</title>
<tgroup cols="3">
<thead>
<row>
<entry>C++ Datatype</entry>
<entry>&rarr; Python</entry>
<entry>&rarr; Java</entry>
</row>
</thead>
<tbody>
<row><entry>bool</entry><entry>bool</entry><entry>boolean</entry></row>
<row><entry>uint16</entry><entry>int | long</entry><entry>short</entry></row>
<row><entry>uint32</entry><entry>int | long</entry><entry>int</entry></row>
<row><entry>uint64</entry><entry>int | long</entry><entry>long</entry></row>
<row><entry>int16</entry><entry>int | long</entry><entry>short</entry></row>
<row><entry>int32</entry><entry>int | long</entry><entry>int</entry></row>
<row><entry>int64</entry><entry>int | long</entry><entry>long</entry></row>
<row><entry>float</entry><entry>float</entry><entry>float</entry></row>
<row><entry>double</entry><entry>float</entry><entry>double</entry></row>
<row><entry>string</entry><entry>unicode</entry><entry>java.lang.String</entry></row>
<row><entry>qpid::types::Uuid</entry><entry>uuid</entry><entry>java.util.UUID</entry></row>
<row><entry>Variant::Map</entry><entry>dict</entry><entry>java.util.Map</entry></row>
<row><entry>Variant::List</entry><entry>list</entry><entry>java.util.List</entry></row>
</tbody>
</tgroup>
</table>
</section>
<section id="section-dotnet-Maps">
<title>Qpid Maps and Lists in .NET</title>
<para>
The .NET binding for the Qpid Messaging API binds .NET managed data types
to C++ <classname>Variant</classname> data types. The following code shows how to
send Map and List structures in a message:
</para>
<example>
<?dbfo keep-together="auto" ?>
<title>Sending Qpid Maps and Lists in .NET C#</title>
<programlisting><![CDATA[
using System;
using Org.Apache.Qpid.Messaging;
// !!! SNIP !!!
Dictionary<string, object> content = new Dictionary<string, object>();
Dictionary<string, object> subMap = new Dictionary<string, object>();
Collection<object> colors = new Collection<object>();
// add simple types
content["id"] = 987654321;
content["name"] = "Widget";
content["percent"] = 0.99;
// add nested amqp/map
subMap["name"] = "Smith";
subMap["number"] = 354;
content["nestedMap"] = subMap;
// add an amqp/list
colors.Add("red");
colors.Add("green");
colors.Add("white");
content["colorsList"] = colors;
// add one of each supported amqp data type
bool mybool = true;
content["mybool"] = mybool;
byte mybyte = 4;
content["mybyte"] = mybyte;
UInt16 myUInt16 = 5;
content["myUInt16"] = myUInt16;
UInt32 myUInt32 = 6;
content["myUInt32"] = myUInt32;
UInt64 myUInt64 = 7;
content["myUInt64"] = myUInt64;
char mychar = 'h';
content["mychar"] = mychar;
Int16 myInt16 = 9;
content["myInt16"] = myInt16;
Int32 myInt32 = 10;
content["myInt32"] = myInt32;
Int64 myInt64 = 11;
content["myInt64"] = myInt64;
Single mySingle = (Single)12.12;
content["mySingle"] = mySingle;
Double myDouble = 13.13;
content["myDouble"] = myDouble;
Guid myGuid = new Guid("000102030405060708090a0b0c0d0e0f");
content["myGuid"] = myGuid;
Message message = new Message(content);
Send(message, true);
]]> </programlisting>
</example>
<para>
The following table shows the mapping between datatypes in .NET and C++.
</para>
<table id="table-dotnet-Maps">
<title>Datatype Mapping between C++ and .NET binding</title>
<tgroup cols="2">
<thead>
<row>
<entry>C++ Datatype</entry>
<entry>&rarr; .NET binding</entry>
</row>
</thead>
<tbody>
<row><entry>void</entry><entry>nullptr</entry></row>
<row><entry>bool</entry><entry>bool</entry></row>
<row><entry>uint8</entry><entry>byte</entry></row>
<row><entry>uint16</entry><entry>UInt16</entry></row>
<row><entry>uint32</entry><entry>UInt32</entry></row>
<row><entry>uint64</entry><entry>UInt64</entry></row>
<row><entry>uint8</entry><entry>char</entry></row>
<row><entry>int16</entry><entry>Int16</entry></row>
<row><entry>int32</entry><entry>Int32</entry></row>
<row><entry>int64</entry><entry>Int64</entry></row>
<row><entry>float</entry><entry>Single</entry></row>
<row><entry>double</entry><entry>Double</entry></row>
<row><entry>string</entry><entry>string
<footnote id="callout-dotnet-string">
<para>Strings are currently interpreted only with UTF-8 encoding.</para>
</footnote></entry></row>
<row><entry>qpid::types::Uuid</entry><entry>Guid</entry></row>
<row><entry>Variant::Map</entry><entry><![CDATA[Dictionary<string, object>]]>
<footnoteref linkend="callout-dotnet-string"/></entry></row>
<row><entry>Variant::List</entry><entry><![CDATA[Collection<object>]]>
<footnoteref linkend="callout-dotnet-string"/></entry></row>
</tbody>
</tgroup>
</table>
</section>
</section>
<section>
<title>The Request / Response Pattern</title>
<para>Request / Response applications use the reply-to property,
described in <xref
linkend="table-amqp0-10-message-properties"/>, to allow a server
to respond to the client that sent a message. A server sets up a
service queue, with a name known to clients. A client creates a
private queue for the server's response, creates a message for a
request, sets the request's reply-to property to the address of
the client's response queue, and sends the request to the
service queue. The server sends the response to the address
specified in the request's reply-to property.
</para>
<example>
<title>Request / Response Applications in C++</title>
<para>This example shows the C++ code for a client and server
that use the request / response pattern.</para>
<para>The server creates a service queue and waits for a
message to arrive. If it receives a message, it sends a
message back to the sender.</para>
<programlisting><![CDATA[Receiver receiver = session.createReceiver("service_queue; {create: always}");
Message request = receiver.fetch();
const Address&amp; address = request.getReplyTo(); // Get "reply-to" from request ...
if (address) {
Sender sender = session.createSender(address); // ... send response to "reply-to"
Message response("pong!");
sender.send(response);
session.acknowledge();
}
]]></programlisting>
<para>The client creates a sender for the service queue, and
also creates a response queue that is deleted when the
client closes the receiver for the response queue. In the C++
client, if the address starts with the character
<literal>#</literal>, it is given a unique name.</para>
<programlisting><![CDATA[
Sender sender = session.createSender("service_queue");
Address responseQueue("#response-queue; {create:always, delete:always}");
Receiver receiver = session.createReceiver(responseQueue);
Message request;
request.setReplyTo(responseQueue);
request.setContent("ping");
sender.send(request);
Message response = receiver.fetch();
std::cout << request.getContent() << " -> " << response.getContent() << std::endl;
]]> </programlisting>
<para>The client sends the string <literal>ping</literal> to
the server. The server sends the response
<literal>pong</literal> back to the same client, using the
<varname>replyTo</varname> property.</para>
</example>
<!--
<example>
<title>Request / Response Applications in Python</title>
<programlisting>### TODO</programlisting>
</example>
-->
</section>
<section>
<title>Performance Tips</title>
<itemizedlist>
<listitem>
<para>Consider prefetching messages for receivers (see
<xref linkend="prefetch"/>). This helps eliminate roundtrips
and increases throughput. Prefetch is disabled by default,
and enabling it is the most effective means of improving
throughput of received messages.</para>
</listitem>
<listitem>
<para>Send messages asynchronously. Again, this helps
eliminate roundtrips and increases throughput. The C++ and
.NET clients send asynchronously by default, however the
python client defaults to synchronous sends. </para>
</listitem>
<listitem>
<para>Acknowledge messages in batches (see
<xref linkend="acknowledgements"/>). Rather than
acknowledging each message individually, consider issuing
acknowledgements after n messages and/or after a particular
duration has elapsed.</para>
</listitem>
<listitem>
<para>Tune the sender capacity (see
<xref linkend="replay"/>). If the capacity is too low the
sender may block waiting for the broker to confirm receipt
of messages, before it can free up more capacity.</para>
</listitem>
<listitem>
<para>If you are setting a reply-to address on messages
being sent by the c++ client, make sure the address type is
set to either queue or topic as appropriate. This avoids the
client having to determine which type of node is being
refered to, which is required when hanling reply-to in AMQP
0-10. </para>
</listitem>
<listitem>
<para>For latency sensitive applications, setting tcp-nodelay
on qpidd and on client connections can help reduce the
latency.</para>
</listitem>
</itemizedlist>
</section>
<section>
<title>Cluster Failover</title>
<para>The messaging broker can be run in clustering mode, which provides high reliability through replicating state between brokers in the cluster. If one broker in a cluster fails, clients can choose another broker in the cluster and continue their work. Each broker in the cluster also advertises the addresses of all known brokers
<footnote><para>This is done via the amq.failover exchange in AMQP 0-10</para></footnote>
. A client can use this information to dynamically keep the list of reconnection urls up to date.</para>
<para>In C++, the <classname>FailoverUpdates</classname> class provides this functionality:</para>
<example>
<title>Tracking cluster membership</title>
<para>In C++:</para>
<programlisting><![CDATA[
#include <qpid/messaging/FailoverUpdates.h>
...
Connection connection("localhost:5672");
connection.setOption("reconnect", true);
try {
connection.open();
std::auto_ptr<FailoverUpdates> updates(new FailoverUpdates(connection));
]]>
</programlisting>
<para>In python:</para>
<programlisting><![CDATA[
import qpid.messaging.util
...
connection = Connection("localhost:5672")
connection.reconnect = True
try:
connection.open()
auto_fetch_reconnect_urls(connection)
]]>
</programlisting>
<para>
In .NET C#:
</para>
<programlisting>
using Org.Apache.Qpid.Messaging;
...
connection = new Connection(&#34;localhost:5672&#34;);
connection.SetOption("reconnect", true);
try {
connection.Open();
FailoverUpdates failover = new FailoverUpdates(connection);
</programlisting>
</example>
</section>
<section>
<title>Logging</title>
<para>To simplify debugging, Qpid provides a logging facility
that prints out messaging events.</para>
<section>
<title>Logging in C++</title>
<para>
The Qpidd broker and C++ clients can both use environment variables to enable logging. Linux and Windows systems use the same named environment variables and values.
</para>
<para>Use QPID_LOG_ENABLE to set the level of logging you are interested in (trace, debug, info, notice, warning, error, or critical):
</para>
<screen>
export QPID_LOG_ENABLE=&#34;warning+&#34;
</screen>
<para>
The Qpidd broker and C++ clients use QPID_LOG_OUTPUT to determine where logging output should be sent. This is either a file name or the special values stderr, stdout, or syslog:
</para>
<screen>
export QPID_LOG_TO_FILE=&#34;/tmp/myclient.out&#34;
</screen>
<para>
From a Windows command prompt, use the following command format to set the environment variables:
</para>
<screen>
set QPID_LOG_ENABLE=warning+
set QPID_LOG_TO_FILE=D:\tmp\myclient.out
</screen>
</section>
<section>
<title>Logging in Python</title>
<para>
The Python client library supports logging using the standard Python logging module. The easiest way to do logging is to use the <command>basicConfig()</command>, which reports all warnings and errors:
</para>
<programlisting>from logging import basicConfig
basicConfig()
</programlisting>
<para>
Qpidd also provides a convenience method that makes it easy to specify the level of logging desired. For instance, the following code enables logging at the <command>DEBUG</command> level:
</para>
<programlisting>from qpid.log import enable, DEBUG
enable("qpid.messaging.io", DEBUG)
</programlisting>
<para>
For more information on Python logging, see <ulink url="http://docs.python.org/lib/node425.html">http://docs.python.org/lib/node425.html</ulink>. For more information on Qpid logging, use <command>$ pydoc qpid.log</command>.
</para>
</section>
</section>
<section id="section-amqp0-10-mapping">
<title>The AMQP 0-10 mapping</title>
<para>
This section describes the AMQP 0-10 mapping for the Qpid
Messaging API.
</para>
<para>
The interaction with the broker triggered by creating a sender
or receiver depends on what the specified address resolves
to. Where the node type is not specified in the address, the
client queries the broker to determine whether it refers to a
queue or an exchange.
</para>
<para>
When sending to a queue, the queue's name is set as the
routing key and the message is transfered to the default (or
nameless) exchange. When sending to an exchange, the message
is transfered to that exchange and the routing key is set to
the message subject if one is specified. A default subject may
be specified in the target address. The subject may also be
set on each message individually to override the default if
required. In each case any specified subject is also added as
a qpid.subject entry in the application-headers field of the
message-properties.
</para>
<para>
When receiving from a queue, any subject in the source address
is currently ignored. The client sends a message-subscribe
request for the queue in question. The accept-mode is
determined by the reliability option in the link properties;
for unreliable links the accept-mode is none, for reliable
links it is explicit. The default for a queue is reliable. The
acquire-mode is determined by the value of the mode option. If
the mode is set to browse the acquire mode is not-acquired,
otherwise it is set to pre-acquired. The exclusive and
arguments fields in the message-subscribe command can be
controlled using the x-subscribe map.
</para>
<para>
When receiving from an exchange, the client creates a
subscription queue and binds that to the exchange. The
subscription queue's arguments can be specified using the
x-declare map within the link properties. The reliability
option determines most of the other parameters. If the
reliability is set to unreliable then an auto-deleted,
exclusive queue is used meaning that if the client or
connection fails messages may be lost. For exactly-once the
queue is not set to be auto-deleted. The durability of the
subscription queue is determined by the durable option in the
link properties. The binding process depends on the type of
the exchange the source address resolves to.
</para>
<itemizedlist>
<listitem>
<para>
For a topic exchange, if no subject is specified and no
x-bindings are defined for the link, the subscription
queue is bound using a wildcard matching any routing key
(thus satisfying the expectation that any message sent to
that address will be received from it). If a subject is
specified in the source address however, it is used for
the binding key (this means that the subject in the source
address may be a binding pattern including wildcards).
</para>
</listitem>
<listitem>
<para>
For a fanout exchange the binding key is irrelevant to
matching. A receiver created from a source address that
resolves to a fanout exchange receives all messages
sent to that exchange regardless of any subject the source
address may contain. An x-bindings element in the link
properties should be used if there is any need to set the
arguments to the bind.
</para>
</listitem>
<listitem>
<para>
For a direct exchange, the subject is used as the binding
key. If no subject is specified an empty string is used as
the binding key.
</para>
</listitem>
<listitem>
<para>
For a headers exchange, if no subject is specified the
binding arguments simply contain an x-match entry and no
other entries, causing all messages to match. If a subject
is specified then the binding arguments contain an x-match
entry set to all and an entry for qpid.subject whose value
is the subject in the source address (this means the
subject in the source address must match the message
subject exactly). For more control the x-bindings element
in the link properties must be used.
</para>
</listitem>
<listitem>
<para>
For the XML exchange,<footnote><para>Note that the XML
exchange is not a standard AMQP exchange type. It is a
Qpid extension and is currently only supported by the C++
broker.</para></footnote> if a subject is specified it is
used as the binding key and an XQuery is defined that
matches any message with that value for
qpid.subject. Again this means that only messages whose
subject exactly match that specified in the source address
are received. If no subject is specified then the empty
string is used as the binding key with an xquery that will
match any message (this means that only messages with an
empty string as the routing key will be received). For more
control the x-bindings element in the link properties must
be used. A source address that resolves to the XML
exchange must contain either a subject or an x-bindings
element in the link properties as there is no way at
present to receive any message regardless of routing key.
</para>
</listitem>
</itemizedlist>
<para>
If an x-bindings list is present in the link options a binding
is created for each element within that list. Each element is
a nested map that may contain values named queue, exchange,
key or arguments. If the queue value is absent the queue name
the address resolves to is implied. If the exchange value is
absent the exchange name the address resolves to is implied.
</para>
<para>The following table shows how Qpid Messaging API message
properties are mapped to AMQP 0-10 message properties and
delivery properties. In this table <varname>msg</varname>
refers to the Message class defined in the Qpid Messaging API,
<varname>mp</varname> refers to an AMQP 0-10
<varname>message-properties</varname> struct, and
<varname>dp</varname> refers to an AMQP 0-10
<varname>delivery-properties</varname> struct.</para>
<table id="table-amqp0-10-message-properties" pgwide="1">
<title>Mapping to AMQP 0-10 Message Properties</title>
<tgroup cols="3">
<thead>
<colspec colnum="1" colname="Python API" colwidth="3*"/>
<colspec colnum="2" colname="C++ API" colwidth="3*"/>
<colspec colnum="3" colname="AMPQ 0-10 Property" colwidth="6*"/>
<row>
<entry>Python API</entry>
<entry>C++ API
<footnote>
<para>
The .NET Binding for C++ Messaging provides all the
message and delivery properties described in the C++ API.
See <xref linkend="table-Dotnet-Binding-Message" /> .
</para>
</footnote>
</entry>
<entry>AMQP 0-10 Property<footnote><para>In these entries, <literal>mp</literal> refers to an AMQP message property, and <literal>dp</literal> refers to an AMQP delivery property.</para></footnote></entry>
</row>
</thead>
<tbody>
<row>
<entry>msg.id</entry><entry>msg.{get,set}MessageId()</entry><entry>mp.message_id</entry>
</row>
<row>
<entry>msg.subject</entry><entry>msg.{get,set}Subject()</entry><entry>mp.application_headers["qpid.subject"]</entry>
</row>
<row>
<entry>msg.user_id</entry><entry>msg.{get,set}UserId()</entry><entry>mp.user_id</entry>
</row>
<row>
<entry>msg.reply_to</entry><entry>msg.{get,set}ReplyTo()</entry><entry>mp.reply_to<footnote><para>The reply_to is converted from the protocol representation into an address.</para></footnote></entry>
</row>
<row>
<entry>msg.correlation_id</entry><entry>msg.{get,set}CorrelationId()</entry><entry>mp.correlation_id</entry>
</row>
<row>
<entry>msg.durable</entry><entry>msg.{get,set}Durable()</entry><entry>dp.delivery_mode == delivery_mode.persistent<footnote><para>Note that msg.durable is a boolean, not an enum.</para></footnote></entry>
</row>
<row>
<entry>msg.priority</entry><entry>msg.{get,set}Priority()</entry><entry>dp.priority</entry>
</row>
<row>
<entry>msg.ttl</entry><entry>msg.{get,set}Ttl()</entry><entry>dp.ttl</entry>
</row>
<row>
<entry>msg.redelivered</entry><entry>msg.{get,set}Redelivered()</entry><entry>dp.redelivered</entry>
</row>
<row><entry>msg.properties</entry><entry>msg.{get,set}Properties()</entry><entry>mp.application_headers</entry>
</row>
<row>
<entry>msg.content_type</entry><entry>msg.{get,set}ContentType()</entry><entry>mp.content_type</entry>
</row>
</tbody>
</tgroup>
</table>
<para>The 0-10 mapping also recognises certain special property
keys. If the properties contain entries for <literal>x-amqp-0-10.app-id</literal>
or <literal>x-amqp-0-10.content-encoding</literal>, the values will be used to
set <literal>message-properties.app-id</literal> and
<literal>message-properties.content-encoding</literal> on the
resulting 0-10 message transfer. Likewise if an incoming
transfer has those properties set, they will be exposed in the
same manner. In addition the routing key on incoming transfers
will be exposed directly via the custom property with key
<literal>x-amqp-0-10.routing-key</literal>.</para>
</section>
</chapter>
<chapter id="QpidJMS">
<title>Using the Qpid JMS client</title>
<section>
<title>A Simple Messaging Program in Java JMS</title>
<para>The following program shows how to send and receive a
message using the Qpid JMS client. JMS programs typically use
JNDI to obtain connection factory and destination objects which
the application needs. In this way the configuration is kept
separate from the application code itself.</para>
<para>In this example, we create a JNDI context using a
properties file, use the context to lookup a connection factory,
create and start a connection, create a session, and lookup a
destination from the JNDI context. Then we create a producer and
a consumer, send a message with the producer and receive it with
the consumer. This code should be straightforward for anyone
familiar with Java JMS.</para>
<example>
<title>"Hello world!" in Java</title>
<programlisting lang="java">
package org.apache.qpid.example.jmsexample.hello;
import javax.jms.*;
import javax.naming.Context;
import javax.naming.InitialContext;
import java.util.Properties;
public class Hello {
public Hello() {
}
public static void main(String[] args) {
Hello producer = new Hello();
producer.runTest();
}
private void runTest() {
try {
Properties properties = new Properties();
properties.load(this.getClass().getResourceAsStream("hello.properties")); <co id="hello-java-properties" linkends="callout-java-properties"/>
Context context = new InitialContext(properties); <co id="hello-java-context" linkends="callout-java-context"/>
ConnectionFactory connectionFactory
= (ConnectionFactory) context.lookup("qpidConnectionfactory"); <co id="hello-java-connection-factory" linkends="callout-java-connection-factory"/>
Connection connection = connectionFactory.createConnection(); <co id="hello-java-connection" linkends="callout-java-connection"/>
connection.start(); <co id="hello-java-start" linkends="callout-java-start"/>
Session session=connection.createSession(false,Session.AUTO_ACKNOWLEDGE);<co id="hello-java-session" linkends="callout-java-session"/>
Destination destination = (Destination) context.lookup("topicExchange"); <co id="hello-java-destination" linkends="callout-java-destination"/>
MessageProducer messageProducer = session.createProducer(destination); <co id="hello-java-producer" linkends="callout-java-producer"/>
MessageConsumer messageConsumer = session.createConsumer(destination); <co id="hello-java-consumer" linkends="callout-java-consumer"/>
TextMessage message = session.createTextMessage("Hello world!");
messageProducer.send(message);
message = (TextMessage)messageConsumer.receive(); <co id="hello-java-receive" linkends="callout-java-receive"/>
System.out.println(message.getText());
connection.close(); <co id="hello-java-close" linkends="callout-java-close"/>
context.close(); <co id="hello-java-jndi-close" linkends="callout-java-jndi-close"/>
}
catch (Exception exp) {
exp.printStackTrace();
}
}
}
</programlisting>
</example>
<calloutlist>
<callout id="callout-java-properties" arearefs="hello-java-properties">
<para>Loads the JNDI properties file, which specifies connection properties, queues, topics, and addressing options. See <xref linkend="QpidJNDI"/> for details.</para>
</callout>
<callout id="callout-java-context" arearefs="hello-java-context">
<para>Creates the JNDI initial context.</para>
</callout>
<callout id="callout-java-connection-factory" arearefs="hello-java-connection-factory">
<para>Creates a JMS connection factory for Qpid.</para>
</callout>
<callout id="callout-java-connection" arearefs="hello-java-connection">
<para>Creates a JMS connection.</para>
</callout>
<callout id="callout-java-start" arearefs="hello-java-start">
<para>Activates the connection.</para>
</callout>
<callout id="callout-java-session" arearefs="hello-java-session">
<para>Creates a session. This session is not transactional (transactions='false'), and messages are automatically acknowledged.</para>
</callout>
<callout id="callout-java-destination" arearefs="hello-java-destination">
<para>Creates a destination for the topic exchange, so senders and receivers can use it.</para>
</callout>
<callout id="callout-java-producer" arearefs="hello-java-producer">
<para>Creates a producer that sends messages to the topic exchange.</para>
</callout>
<callout id="callout-java-consumer" arearefs="hello-java-consumer">
<para>Creates a consumer that reads messages from the topic exchange.</para>
</callout>
<callout id="callout-java-receive" arearefs="hello-java-receive">
<para>Reads the next available message.</para>
</callout>
<callout id="callout-java-close" arearefs="hello-java-close">
<para>Closes the connection, all sessions managed by the connection, and all senders and receivers managed by each session.</para>
</callout>
<callout id="callout-java-jndi-close" arearefs="hello-java-jndi-close">
<para>Closes the JNDI context.</para>
</callout>
</calloutlist>
<para>The contents of the hello.properties file are shown below.</para>
<example>
<title>JNDI Properties File for "Hello world!" example</title>
<programlisting>
java.naming.factory.initial
= org.apache.qpid.jndi.PropertiesFileInitialContextFactory
# connectionfactory.[jndiname] = [ConnectionURL]
connectionfactory.qpidConnectionfactory
= amqp://guest:guest@clientid/test?brokerlist='tcp://localhost:5672' <co id="hello-properties-connectionfactory" linkends="callout-hello-properties-connectionfactory"/>
# destination.[jndiname] = [address_string]
destination.topicExchange = amq.topic <co id="hello-properties-destination" linkends="callout-hello-properties-destination"/>
</programlisting>
</example>
<calloutlist>
<callout id="callout-hello-properties-connectionfactory" arearefs="hello-properties-connectionfactory">
<para>Defines a connection factory from which connections
can be created. The syntax of a ConnectionURL is given in
<xref linkend="QpidJNDI"/>.</para>
</callout>
<callout id="callout-hello-properties-destination" arearefs="hello-properties-destination">
<para>Defines a destination for which MessageProducers
and/or MessageConsumers can be created to send and receive
messages. The value for the destination in the properties
file is an address string as described in
<xref linkend="section-addresses"/>. In the JMS
implementation MessageProducers are analogous to senders in
the Qpid Message API, and MessageConsumers are analogous to
receivers.</para>
</callout>
</calloutlist>
</section>
<section id="QpidJNDI">
<title>Apache Qpid JNDI Properties for AMQP Messaging</title>
<para>
Apache Qpid defines JNDI properties that can be used to specify JMS Connections and Destinations. Here is a typical JNDI properties file:
</para>
<example>
<title>JNDI Properties File</title>
<programlisting><![CDATA[
java.naming.factory.initial
= org.apache.qpid.jndi.PropertiesFileInitialContextFactory
# connectionfactory.[jndiname] = [ConnectionURL]
connectionfactory.qpidConnectionfactory
= amqp://guest:guest@clientid/test?brokerlist='tcp://localhost:5672'
# destination.[jndiname] = [address_string]
destination.topicExchange = amq.topic
]]></programlisting>
</example>
<para>The following sections describe the JNDI properties that Qpid uses.</para>
<section>
<title>JNDI Properties for Apache Qpid</title>
<para>
Apache Qpid supports the properties shown in the following table:
</para>
<table>
<title>JNDI Properties supported by Apache Qpid</title>
<tgroup cols="2">
<thead>
<row>
<entry>
Property
</entry>
<entry>
Purpose
</entry>
</row>
</thead>
<tbody>
<row>
<entry>
connectionfactory.&lt;jndiname&gt;
</entry>
<entry>
<para>
The Connection URL that the connection factory uses to perform connections.
</para>
</entry>
</row>
<row>
<entry>
queue.&lt;jndiname&gt;
</entry>
<entry>
<para>
A JMS queue, which is implemented as an amq.direct exchange in Apache Qpid.
</para>
</entry>
</row>
<row>
<entry>
topic.&lt;jndiname&gt;
</entry>
<entry>
<para>
A JMS topic, which is implemented as an amq.topic exchange in Apache Qpid.
</para>
</entry>
</row>
<row>
<entry>
destination.&lt;jndiname&gt;
</entry>
<entry>
<para>
Can be used for defining all amq destinations,
queues, topics and header matching, using an
address string.
<footnote><para>Binding URLs, which were used in
earlier versions of the Qpid Java JMS client, can
still be used instead of address
strings.</para></footnote>
</para>
</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section id="section-jms-connection-url">
<title>Connection URLs</title>
<para>
In JNDI properties, a Connection URL specifies properties for a connection. The format for a Connection URL is:
</para>
<programlisting>amqp://[&lt;user&gt;:&lt;pass&gt;@][&lt;clientid&gt;]&lt;virtualhost&gt;[?&lt;option&gt;=&#39;&lt;value&gt;&#39;[&amp;&lt;option&gt;=&#39;&lt;value&gt;&#39;]]
</programlisting>
<para>
For instance, the following Connection URL specifies a user name, a password, a client ID, a virtual host ("test"), a broker list with a single broker, and a TCP host with the host name <quote>localhost</quote> using port 5672:
</para>
<programlisting>amqp://username:password@clientid/test?brokerlist=&#39;tcp://localhost:5672&#39;
</programlisting>
<para>
Apache Qpid supports the following properties in Connection URLs:
</para>
<table pgwide="1">
<title>Connection URL Properties</title>
<tgroup cols="3">
<thead>
<row>
<entry>
Option
</entry>
<entry>
Type
</entry>
<entry>
Description
</entry>
</row>
</thead>
<tbody>
<row>
<entry>
brokerlist
</entry>
<entry>
see below
</entry>
<entry>
The broker to use for this connection. In the current release, precisely one broker must be specified.
</entry>
</row>
<row>
<entry>
maxprefetch
</entry>
<entry>
--
</entry>
<entry>
The maximum number of pre-fetched messages per destination.
</entry>
</row>
<row>
<entry>
sync_publish
</entry>
<entry>
{'persistent' | 'all'}
</entry>
<entry>
A sync command is sent after every persistent message to guarantee that it has been received; if the value is 'persistent', this is done only for persistent messages.
</entry>
</row>
<row>
<entry>
sync_ack
</entry>
<entry>
Boolean
</entry>
<entry>
A sync command is sent after every acknowledgement to guarantee that it has been received.
</entry>
</row>
<row>
<entry>
use_legacy_map_msg_format
</entry>
<entry>
Boolean
</entry>
<entry>
If you are using JMS Map messages and deploying a new client with any JMS client older than 0.8 release, you must set this to true to ensure the older clients can understand the map message encoding.
</entry>
</row>
<row>
<entry>
failover
</entry>
<entry>
{'roundrobin' | 'failover_exchange'}
</entry>
<entry>
If roundrobin is selected it will try each broker given in the broker list.
If failover_exchange is selected it connects to the initial broker given in the broker URL and will receive membership updates via the failover exchange.
</entry>
</row>
</tbody>
</tgroup>
</table>
<para>
Broker lists are specified using a URL in this format:
</para>
<programlisting>brokerlist=&lt;transport&gt;://&lt;host&gt;[:&lt;port&gt;](?&lt;param>=&lt;value>)?(&amp;&lt;param>=&lt;value>)*</programlisting>
<para>
For instance, this is a typical broker list:
</para>
<programlisting>brokerlist=&#39;tcp://localhost:5672&#39;
</programlisting>
<para>
A broker list can contain more than one broker address; if so, the connection is made to the first broker in the list that is available. In general, it is better to use the failover exchange when using multiple brokers, since it allows applications to fail over if a broker goes down.
</para>
<example>
<title>Broker Lists</title>
<para>A broker list can specify properties to be used when connecting to the broker, such as security options. This broker list specifies options for a Kerberos connection using GSSAPI:</para>
<programlisting><![CDATA[
amqp://guest:guest@test/test?sync_ack='true'
&brokerlist='tcp://ip1:5672?sasl_mechs='GSSAPI'
]]></programlisting>
<para>This broker list specifies SSL options:</para>
<programlisting><![CDATA[
amqp://guest:guest@test/test?sync_ack='true'
&brokerlist='tcp://ip1:5672?ssl='true'&ssl_cert_alias='cert1'
]]></programlisting>
</example>
<para>The following broker list options are supported.</para>
<table pgwide="1">
<title>Broker List Options</title>
<tgroup cols="3">
<thead>
<row>
<entry>
Option
</entry>
<entry>
Type
</entry>
<entry>
Description
</entry>
</row>
</thead>
<tbody>
<row>
<entry>
heartbeat
</entry>
<entry>
integer
</entry>
<entry>
frequency of heartbeat messages (in seconds)
</entry>
</row>
<row>
<entry>
sasl_mechs
</entry>
<entry>
--
</entry>
<entry>
For secure applications, we suggest CRAM-MD5,
DIGEST-MD5, or GSSAPI. The ANONYMOUS method is not
secure. The PLAIN method is secure only when used
together with SSL. For Kerberos, sasl_mechs must be
set to GSSAPI, sasl_protocol must be set to the
principal for the qpidd broker, e.g. qpidd/, and
sasl_server must be set to the host for the SASL
server, e.g. sasl.com. SASL External is supported
using SSL certification, e.g.
<literal>ssl='true'&amp;sasl_mechs='EXTERNAL'</literal>
</entry>
</row>
<row>
<entry>
sasl_encryption
</entry>
<entry>
Boolean
</entry>
<entry>
If <literal>sasl_encryption='true'</literal>, the JMS client attempts to negotiate a security layer with the broker using GSSAPI to encrypt the connection. Note that for this to happen, GSSAPI must be selected as the sasl_mech.
</entry>
</row>
<row>
<entry>
ssl
</entry>
<entry>
Boolean
</entry>
<entry>
If <literal>ssl='true'</literal>, the JMS client will encrypt the connection using SSL.
</entry>
</row>
<row>
<entry>
tcp_nodelay
</entry>
<entry>
Boolean
</entry>
<entry>
If <literal>tcp_nodelay='true'</literal>, TCP packet
batching is disabled.
</entry>
</row>
<row>
<entry>
sasl_protocol
</entry>
<entry>
--
</entry>
<entry>
Used only for
Kerberos. <literal>sasl_protocol</literal> must be
set to the principal for the qpidd broker,
e.g. <literal>qpidd/</literal>
</entry>
</row>
<row>
<entry>
sasl_server
</entry>
<entry>
--
</entry>
<entry>
For Kerberos, sasl_mechs must be set to GSSAPI,
sasl_server must be set to the host for the SASL
server, e.g. <literal>sasl.com</literal>.
</entry>
</row>
<row>
<entry>
trust_store
</entry>
<entry>
--
</entry>
<entry>
path to Keberos trust store
</entry>
</row>
<row>
<entry>
trust_store_password
</entry>
<entry>
</entry>
<entry>
Kerberos trust store password
</entry>
</row>
<row>
<entry>
key_store
</entry>
<entry>
</entry>
<entry>
path to Kerberos key store
</entry>
</row>
<row>
<entry>
key_store_password
</entry>
<entry>
--
</entry>
<entry>
Kerberos key store password
</entry>
</row>
<row>
<entry>
ssl_verify_hostname
</entry>
<entry>
Boolean
</entry>
<entry>
When using SSL you can enable hostname verification
by using "ssl_verify_hostname=true" in the broker
URL.
</entry>
</row>
<row>
<entry>
ssl_cert_alias
</entry>
<entry>
</entry>
<entry>
If multiple certificates are present in the keystore, the alias will be used to extract the correct certificate.
</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
</section>
<section>
<title>Java JMS Message Properties</title>
<para>The following table shows how Qpid Messaging API message
properties are mapped to AMQP 0-10 message properties and
delivery properties. In this table <varname>msg</varname>
refers to the Message class defined in the Qpid Messaging API,
<varname>mp</varname> refers to an AMQP 0-10
<varname>message-properties</varname> struct, and
<varname>dp</varname> refers to an AMQP 0-10
<varname>delivery-properties</varname> struct.</para>
<table >
<title>Java JMS Mapping to AMQP 0-10 Message Properties</title>
<tgroup cols="2">
<thead>
<row>
<entry>Java JMS Message Property</entry>
<entry>AMQP 0-10 Property<footnote><para>In these entries, <literal>mp</literal> refers to an AMQP message property, and <literal>dp</literal> refers to an AMQP delivery property.</para></footnote></entry>
</row>
</thead>
<tbody>
<row>
<entry>JMSMessageID</entry><entry>mp.message_id</entry>
</row>
<row>
<entry>qpid.subject<footnote><para>This is a custom JMS property, set automatically by the Java JMS client implementation.</para></footnote></entry><entry>mp.application_headers["qpid.subject"]</entry>
</row>
<row>
<entry>JMSXUserID</entry><entry>mp.user_id</entry>
</row>
<row>
<entry>JMSReplyTo</entry><entry>mp.reply_to<footnote><para>The reply_to is converted from the protocol representation into an address.</para></footnote></entry>
</row>
<row>
<entry>JMSCorrelationID</entry><entry>mp.correlation_id</entry>
</row>
<row>
<entry>JMSDeliveryMode</entry><entry>dp.delivery_mode</entry>
</row>
<row>
<entry>JMSPriority</entry><entry>dp.priority</entry>
</row>
<row>
<entry>JMSExpiration</entry><entry>dp.ttl<footnote><para>JMSExpiration = dp.ttl + currentTime</para></footnote></entry>
</row>
<row>
<entry>JMSRedelivered</entry><entry>dp.redelivered</entry>
</row>
<row>
<entry>JMS Properties</entry><entry>mp.application_headers</entry>
</row>
<row>
<entry>JMSType</entry><entry>mp.content_type</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section id="section-JMS-MapMessage">
<title>JMS MapMessage Types</title>
<para>Qpid supports the Java JMS <classname>MapMessage</classname> interface, which provides support for maps in messages. The following code shows how to send a <classname>MapMessage</classname> in Java JMS.</para>
<example>
<title>Sending a Java JMS MapMessage</title>
<programlisting><![CDATA[
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.jms.Connection;
import javax.jms.Destination;
import javax.jms.MapMessage;
import javax.jms.MessageProducer;
import javax.jms.Session;
import org.apache.qpid.client.AMQAnyDestination;
import org.apache.qpid.client.AMQConnection;
import edu.emory.mathcs.backport.java.util.Arrays;
// !!! SNIP !!!
MessageProducer producer = session.createProducer(queue);
MapMessage m = session.createMapMessage();
m.setIntProperty("Id", 987654321);
m.setStringProperty("name", "Widget");
m.setDoubleProperty("price", 0.99);
List<String> colors = new ArrayList<String>();
colors.add("red");
colors.add("green");
colors.add("white");
m.setObject("colours", colors);
Map<String,Double> dimensions = new HashMap<String,Double>();
dimensions.put("length",10.2);
dimensions.put("width",5.1);
dimensions.put("depth",2.0);
m.setObject("dimensions",dimensions);
List<List<Integer>> parts = new ArrayList<List<Integer>>();
parts.add(Arrays.asList(new Integer[] {1,2,5}));
parts.add(Arrays.asList(new Integer[] {8,2,5}));
m.setObject("parts", parts);
Map<String,Object> specs = new HashMap<String,Object>();
specs.put("colours", colors);
specs.put("dimensions", dimensions);
specs.put("parts", parts);
m.setObject("specs",specs);
producer.send(m);
]]></programlisting>
</example>
<para>The following table shows the datatypes that can be sent in a <classname>MapMessage</classname>, and the corresponding datatypes that will be received by clients in Python or C++.</para>
<table id="table-Java-Maps">
<title>Java Datatypes in Maps</title>
<tgroup cols="3">
<thead>
<row>
<entry>Java Datatype</entry>
<entry>&rarr; Python</entry>
<entry>&rarr; C++</entry>
</row>
</thead>
<tbody>
<row><entry>boolean</entry><entry>bool</entry><entry>bool</entry></row>
<row><entry>short</entry><entry>int | long</entry><entry>int16</entry></row>
<row><entry>int</entry><entry>int | long</entry><entry>int32</entry></row>
<row><entry>long</entry><entry>int | long</entry><entry>int64</entry></row>
<row><entry>float</entry><entry>float</entry><entry>float</entry></row>
<row><entry>double</entry><entry>float</entry><entry>double</entry></row>
<row><entry>java.lang.String</entry><entry>unicode</entry><entry>std::string</entry></row>
<row><entry>java.util.UUID</entry><entry>uuid</entry><entry>qpid::types::Uuid</entry></row>
<row><entry>java.util.Map<footnote><para>In Qpid, maps can nest. This goes beyond the functionality required by the JMS specification.</para></footnote></entry><entry>dict</entry><entry>Variant::Map</entry></row>
<row><entry>java.util.List</entry><entry>list</entry><entry>Variant::List</entry></row>
</tbody>
</tgroup>
</table>
</section>
<section id="section-JMS-Logging">
<title>JMS Client Logging</title>
<para>The JMS Client logging is handled using the Simple Logging Facade for Java (<ulink url="http://www.slf4j.org/">SLF4J</ulink>). As the name implies, slf4j is a facade that delegates to other logging systems like log4j or JDK 1.4 logging. For more information on how to configure slf4j for specific logging systems, please consult the slf4j documentation.</para>
<para>When using the log4j binding, please set the log level for org.apache.qpid explicitly. Otherwise log4j will default to DEBUG which will degrade performance considerably due to excessive logging. The recommended logging level for production is <literal>WARN</literal>.</para>
<para>The following example shows the logging properties used to configure client logging for slf4j using the log4j binding. These properties can be placed in a log4j.properties file and placed in the <varname>CLASSPATH</varname>, or they can be set explicitly using the <literal>-Dlog4j.configuration</literal> property.</para>
<example>
<title>log4j Logging Properties</title>
<programlisting><![CDATA[
log4j.logger.org.apache.qpid=WARN, console
log4j.additivity.org.apache.qpid=false
log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.Threshold=all
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=%t %d %p [%c{4}] %m%n
]]></programlisting>
</example>
</section>
<section>
<title>Configuring the JMS Client</title>
<para>The Qpid JMS Client allows several configuration options to customize it's behaviour at different levels of granualarity.</para>
<itemizedlist>
<listitem>
<para>
JVM level using JVM arguments : Configuration that affects all connections, sessions, consumers and producers created within that JVM.
</para>
<para>Ex. <varname>-Dmax_prefetch=1000</varname> property specifies the message credits to use.</para>
</listitem>
<listitem>
<para>
Connection level using Connection/Broker properties : Affects the respective connection and sessions, consumers and produces created by that connection.
</para>
<para>Ex. <varname>amqp://guest:guest@test/test?max_prefetch='1000'
&amp;brokerlist='tcp://localhost:5672'
</varname> property specifies the message credits to use. This overrides any value specified via the JVM argument <varname>max_prefetch</varname>.</para>
<para>Please refer to the <xref linkend="section-jms-connection-url"/> section for a complete list of all properties and how to use them.</para>
</listitem>
<listitem>
<para>
Destination level using Addressing options : Affects the producer(s) and consumer(s) created using the respective destination.
</para>
<para>Ex. <varname>my-queue; {create: always, link:{capacity: 10}}</varname>, where <varname>capacity</varname> option specifies the message credits to use. This overrides any connection level configuration.</para>
<para>Please refer to the <xref linkend="section-addresses"/> section for a complete understanding of addressing and it's various options.</para>
</listitem>
</itemizedlist>
<para>Some of these config options are available at all three levels (Ex. <varname>max_prefetch</varname>), while others are available only at JVM or connection level.</para>
<section>
<title>Qpid JVM Arguments</title>
<table >
<title>Config Options For Connection Behaviour</title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>qpid.amqp.version</entry>
<entry>string</entry>
<entry>0-10</entry>
<entry><para>Sets the AMQP version to be used - currently supports one of {0-8,0-9,0-91,0-10}.</para><para>The client will begin negotiation at the specified version and only negotiate downwards if the Broker does not support the specified version.</para></entry>
</row>
<row>
<entry>qpid.heartbeat</entry>
<entry>int</entry>
<entry>120 (secs)</entry>
<entry>The heartbeat interval in seconds. Two consective misssed heartbeats will result in the connection timing out.<para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
<row>
<entry>ignore_setclientID</entry>
<entry>boolean</entry>
<entry>false</entry>
<entry>If a client ID is specified in the connection URL it's used or else an ID is generated. If an ID is specified after it's been set Qpid will throw an exception. <para>Setting this property to 'true' will disable that check and allow you to set a client ID of your choice later on.</para></entry>
</row>
</tbody>
</tgroup>
</table>
<table >
<title>Config Options For Session Behaviour</title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>qpid.session.command_limit</entry>
<entry>int</entry>
<entry>65536</entry>
<entry>Limits the # of unacked commands</entry>
</row>
<row>
<entry>qpid.session.byte_limit</entry>
<entry>int</entry>
<entry>1048576</entry>
<entry>Limits the # of unacked commands in terms of bytes</entry>
</row>
<row>
<entry>qpid.use_legacy_map_message</entry>
<entry>boolean</entry>
<entry>false</entry>
<entry><para>If set will use the old map message encoding. By default the Map messages are encoded using the 0-10 map encoding.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
</tbody>
</tgroup>
</table>
<table >
<title>Config Options For Consumer Behaviour</title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>max_prefetch</entry>
<entry>int</entry>
<entry>500</entry>
<entry>Maximum number of messages to credits. <para>This could also be set per connection (see connection paramters) or per destination (see the <varname>capacity</varname> option under link properties in addressing).</para></entry>
</row>
<row>
<entry>qpid.session.max_ack_delay</entry>
<entry>long</entry>
<entry>1000 (ms)</entry>
<entry><para>Timer interval to flush message acks in buffer when using AUTO_ACK and DUPS_OK.</para> <para>When using the above ack modes, message acks are batched and sent if one of the following conditions are met (which ever happens first).
<itemizedlist>
<listitem><para>When the ack timer fires.</para></listitem>
<listitem><para>if un_acked_msg_count > max_prefetch/2.</para></listitem>
</itemizedlist>
</para>
<para>The ack timer can be disabled by setting it to 0.</para>
</entry>
</row>
<row>
<entry>sync_ack</entry>
<entry>boolean</entry>
<entry>false</entry>
<entry><para>If set, each message will be acknowledged synchronously. When using AUTO_ACK mode, you need to set this to "true", in order to get the correct behaviour as described by the JMS spec.</para><para>This is set to false by default for performance reasons, therefore by default AUTO_ACK behaves similar to DUPS_OK.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
</tbody>
</tgroup>
</table>
<table >
<title>Config Options For Producer Behaviour</title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>sync_publish</entry>
<entry>string</entry>
<entry>"" (disabled)</entry>
<entry><para>If one of {persistent|all} is set then persistent messages or all messages will be sent synchronously.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
</tbody>
</tgroup>
</table>
<table >
<title>Config Options For Threading</title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>qpid.thread_factory</entry>
<entry>string</entry>
<entry>org.apache.qpid.thread.DefaultThreadFactory</entry>
<entry><para>Specifies the thread factory to use.</para><para>If using a real time JVM, you need to set the above property to <varname>org.apache.qpid.thread.RealtimeThreadFactory</varname>.</para></entry>
</row>
<row>
<entry>qpid.rt_thread_priority</entry>
<entry>int</entry>
<entry>20</entry>
<entry><para>Specifies the priority (1-99) for Real time threads created by the real time thread factory.</para></entry>
</row>
</tbody>
</tgroup>
</table>
<table >
<title>Config Options For I/O</title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>qpid.transport</entry>
<entry>string</entry>
<entry>org.apache.qpid.transport.network.io.IoNetworkTransport</entry>
<entry><para>The transport implementation to be used.</para><para>A user could specify an alternative transport mechanism that implements the <varname>org.apache.qpid.transport.network.NetworkTransport</varname> interface.</para></entry>
</row>
<row>
<entry>qpid.sync_op_timeout</entry>
<entry>long</entry>
<entry>60000</entry>
<entry><para>The length of time (in milliseconds) to wait for a synchronous operation to complete.</para><para>For compatibility with older clients, the synonym <varname>amqj.default_syncwrite_timeout</varname> is supported.</para></entry>
</row>
<row>
<entry>amqj.tcp_nodelay</entry>
<entry>boolean</entry>
<entry>false</entry>
<entry><para>Sets the TCP_NODELAY property of the underlying socket.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
</tbody>
</tgroup>
</table>
<table >
<title>Config Options For Security</title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>qpid.sasl_mechs</entry>
<entry>string</entry>
<entry>PLAIN</entry>
<entry><para>The SASL mechanism to be used. More than one could be specified as a comma separated list.</para><para>We currently support the following mechanisms {PLAIN | GSSAPI | EXTERNAL}.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
<row>
<entry>qpid.sasl_protocol</entry>
<entry>string</entry>
<entry>AMQP</entry>
<entry><para>When using GSSAPI as the SASL mechanism, <varname>sasl_protocol</varname> must be set to the principal for the qpidd broker, e.g. <varname>qpidd</varname>.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
<row>
<entry>qpid.sasl_server_name</entry>
<entry>string</entry>
<entry>localhost</entry>
<entry><para>When using GSSAPI as the SASL mechanism, <varname>sasl_server</varname> must be set to the host for the SASL server, e.g. <varname>example.com</varname>.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
</tbody>
</tgroup>
</table>
<table>
<title>Config Options For Security - Standard JVM properties needed when using GSSAPI as the SASL mechanism.<footnote><para>Please refer to the Java security documentation for a complete understanding of the above properties.</para></footnote></title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>javax.security.auth.useSubjectCredsOnly</entry>
<entry>boolean</entry>
<entry>true</entry>
<entry><para>If set to 'false', forces the SASL GASSPI client to obtain the kerberos credentials explicitly instead of obtaining from the "subject" that owns the current thread.</para></entry>
</row>
<row>
<entry>java.security.auth.login.config</entry>
<entry>string</entry>
<entry></entry>
<entry><para>Specifies the jass configuration file.</para><para><varname>Ex-Djava.security.auth.login.config=myjas.conf</varname>
</para><para>Here is the sample myjas.conf JASS configuration file: <programlisting><![CDATA[
com.sun.security.jgss.initiate {
com.sun.security.auth.module.Krb5LoginModule required useTicketCache=true;
};
]]></programlisting></para></entry>
</row>
</tbody>
</tgroup>
</table>
<table>
<title>Config Options For Security - Using SSL for securing connections or using EXTERNAL as the SASL mechanism.</title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>qpid.ssl_timeout</entry>
<entry>long</entry>
<entry>60000</entry>
<entry><para>Timeout value used by the Java SSL engine when waiting on operations.</para></entry>
</row>
<row>
<entry>qpid.ssl.keyStoreCertType</entry>
<entry>string</entry>
<entry>SunX509</entry>
<entry><para>The certificate type.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
<row>
<entry>qpid.ssl.trustStoreCertType</entry>
<entry>string</entry>
<entry>SunX509</entry>
<entry><para>The certificate type.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
</tbody>
</tgroup>
</table>
<table>
<title>Config Options For Security - Standard JVM properties needed when Using SSL for securing connections or using EXTERNAL as the SASL mechanism.<footnote><para>Qpid allows you to have per connection key and trust stores if required. If specified per connection, the JVM arguments are ignored.</para></footnote></title>
<tgroup cols="4">
<thead>
<row>
<entry>Property Name</entry>
<entry>Type</entry>
<entry>Default Value</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>javax.net.ssl.keyStore</entry>
<entry>string</entry>
<entry>jvm default</entry>
<entry><para>Specifies the key store path.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
<row>
<entry>javax.net.ssl.keyStorePassword</entry>
<entry>string</entry>
<entry>jvm default</entry>
<entry><para>Specifies the key store password.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
<row>
<entry>javax.net.ssl.trustStore</entry>
<entry>string</entry>
<entry>jvm default</entry>
<entry><para>Specifies the trust store path.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
<row>
<entry>javax.net.ssl.trustStorePassword</entry>
<entry>string</entry>
<entry>jvm default</entry>
<entry><para>Specifies the trust store password.</para><para>This could also be set per connection as well (see connection paramters).</para></entry>
</row>
</tbody>
</tgroup>
</table>
</section>
</section>
</chapter>
<chapter id="QpidWCF">
<title>Using the Qpid WCF client</title>
<section>
<title>XML and Binary Bindings</title>
<para>The Qpid WCF client provides two bindings, each with support for
Windows .NET transactions.</para>
<para>The AmqpBinding is suitable for communication between two WCF
applications. By default it uses the WCF binary .NET XML encoder
(BinaryMessageEncodingBindingElement) for efficient message
transmission, but it can also use the text and Message Transmission
Optimization Mechanism (MTOM) encoders. Here is a traditional service
model sample program using the AmqpBinding. It assumes that the queue
"hello_service_node" has been created and configured on the AMQP
broker.</para>
<example><?dbfo keep-together="auto" ?>
<title>Traditional service model "Hello world!" example</title>
<programlisting><![CDATA[
namespace Apache.Qpid.Documentation.HelloService
{
using System;
using System.ServiceModel;
using System.ServiceModel.Channels;
using System.Threading;
using Apache.Qpid.Channel;
[ServiceContract]
public interface IHelloService
{
[OperationContract(IsOneWay = true, Action = "*")]
void SayHello(string greeting);
}
public class HelloService : IHelloService
{
private static int greetingCount;
public static int GreetingCount
{
get { return greetingCount; }
}
public void SayHello(string greeting)
{
Console.WriteLine("Service received: " + greeting);
greetingCount++;
}]]></programlisting>
<programlisting><![CDATA[
static void Main(string[] args)
{
try
{
AmqpBinding amqpBinding = new AmqpBinding();
amqpBinding.BrokerHost = "localhost";
amqpBinding.BrokerPort = 5672;
ServiceHost serviceHost = new ServiceHost(typeof(HelloService));
serviceHost.AddServiceEndpoint(typeof(IHelloService),
amqpBinding, "amqp:hello_service_node");
serviceHost.Open();
// Send the service a test greeting
Uri amqpClientUri=new Uri("amqp:amq.direct?routingkey=hello_service_node");
EndpointAddress clientEndpoint = new EndpointAddress(amqpClientUri);
ChannelFactory<IHelloService> channelFactory =
new ChannelFactory<IHelloService>(amqpBinding, clientEndpoint);
IHelloService clientProxy = channelFactory.CreateChannel();
clientProxy.SayHello("Greetings from WCF client");
// wait for service to process the greeting
while (HelloService.GreetingCount == 0)
{
Thread.Sleep(100);
}
channelFactory.Close();
serviceHost.Close();
}
catch (Exception e)
{
Console.WriteLine("Exception: {0}", e);
}
}
}
}
]]></programlisting>
</example>
<para>The second binding, AmqpBinaryBinding, is suitable for WCF
applications that need to inter-operate with non-WCF clients or that
wish to have direct access to the raw wire representation of the
message body. It relies on a custom encoder to read and write raw
(binary) content which operates similarly to the ByteStream encoder
(introduced in .NET 4.0). The encoder presents an abstract XML
infoset view of the raw message content on input. On output, the
encoder does the reverse and peels away the XML infoset layer exposing
the raw content to the wire representation of the message body. The
application must do the inverse of what the encoder does to allow the
XML infoset wrapper to cancel properly. This is demonstrated in the
following sample code (using the channel programming model) which
directly manipulates or provides callbacks to the WCF message readers
and writers when the content is consumed. In contrast to the
AmqpBinding sample where the simple greeting is encapsulated in a
compressed SOAP envelope, the wire representation of the message
contains the raw content and is identical and fully interoperable with
the Qpid C++ "Hello world!" example.</para>
<example><?dbfo keep-together="auto" ?>
<title>Binary "Hello world!" example using the channel model</title>
<programlisting><![CDATA[
namespace Apache.Qpid.Samples.Channel.HelloWorld
{
using System;
using System.ServiceModel;
using System.ServiceModel.Channels;
using System.ServiceModel.Description;
using System.Text;
using System.Xml;
using Apache.Qpid.Channel;
public class HelloWorld
{
static void Main(string[] args)
{
String broker = "localhost";
int port = 5672;
String target = "amq.topic";
String source = "my_topic_node";
if (args.Length > 0)
{
broker = args[0];
}
if (args.Length > 1)
{
port = int.Parse(args[1]);
}
if (args.Length > 2)
{
target = args[2];
}
if (args.Length > 3)
{
source = args[3];
}
AmqpBinaryBinding binding = new AmqpBinaryBinding();
binding.BrokerHost = broker;
binding.BrokerPort = port;
IChannelFactory<IInputChannel> receiverFactory = binding.BuildChannelFactory<IInputChannel>();
receiverFactory.Open();
IInputChannel receiver = receiverFactory.CreateChannel(new EndpointAddress("amqp:" + source));
receiver.Open();
IChannelFactory<IOutputChannel> senderFactory = binding.BuildChannelFactory<IOutputChannel>();
senderFactory.Open();
IOutputChannel sender = senderFactory.CreateChannel(new EndpointAddress("amqp:" + target));
sender.Open();
sender.Send(Message.CreateMessage(MessageVersion.None, "", new HelloWorldBinaryBodyWriter()));
Message message = receiver.Receive();
XmlDictionaryReader reader = message.GetReaderAtBodyContents();
while (!reader.HasValue)
{
reader.Read();
}
byte[] binaryContent = reader.ReadContentAsBase64();
string text = Encoding.UTF8.GetString(binaryContent);
Console.WriteLine(text);
senderFactory.Close();
receiverFactory.Close();
}
}
public class HelloWorldBinaryBodyWriter : BodyWriter
{
public HelloWorldBinaryBodyWriter() : base (true) {}
protected override void OnWriteBodyContents(XmlDictionaryWriter writer)
{
byte[] binaryContent = Encoding.UTF8.GetBytes("Hello world!");
// wrap the content:
writer.WriteStartElement("Binary");
writer.WriteBase64(binaryContent, 0, binaryContent.Length);
}
}
}
]]></programlisting>
</example>
<para>Bindings define ChannelFactories and ChannelListeners associated with
an AMQP Broker. WCF will frequently automatically create and manage
the life cycle of a these and the resulting IChannel objects used in
message transfer. The binding parameters that can be set are:</para>
<table pgwide="1">
<title>WCF Binding Parameters</title>
<tgroup cols="3">
<thead>
<colspec colnum="1" colwidth="1*"/>
<colspec colnum="2" colwidth="3*"/>
<colspec colnum="3" colwidth="3*"/>
<row>
<entry>Parameter</entry>
<entry>Default</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>
BrokerHost
</entry>
<entry>
localhost
</entry>
<entry>
The broker's server name. Currently the WCF channel
only supports connections with a single broker.
Failover to multiple brokers will be provided in the
future.
</entry>
</row>
<row>
<entry>
BrokerPort
</entry>
<entry>
5672
</entry>
<entry>
The port the broker is listening on.
</entry>
</row>
<row>
<entry>
PrefetchLimit
</entry>
<entry>
0
</entry>
<entry>
The number of messages to prefetch from the amqp
broker before the application actually consumes them.
Increasing this number can dramatically increase the
read performance in some circumstances.
</entry>
</row>
<row>
<entry>
Shared
</entry>
<entry>
false
</entry>
<entry>
Indicates if separate channels to the same broker can
share an underlying AMQP tcp connection (provided they
also share the same authentication credentials).
</entry>
</row>
<row>
<entry>
TransferMode
</entry>
<entry>
buffered
</entry>
<entry>
Indicates whether the channel's encoder uses the WCF
BufferManager cache to temporarily store message
content during the encoding/decoding phase. For small
to medium sized SOAP based messages, buffered is
usually the preferred choice. For binary messages,
streamed TransferMode is the more efficient mode.
</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>Endpoints</title>
<para>In Qpid 0.6 the WCF Endpoints map to simple AMQP 0-10
exchanges (IOutputChannel) or AMQP 0-10 queues (IInputChannel).
The format for an IOutputChannel is</para>
<programlisting><![CDATA[
"amqp:amq.direct" or "amqp:my_exchange?routingkey=my_routing_key"
]]></programlisting>
<para>and for an IInputChannel is</para>
<programlisting><![CDATA[
"amqp:my_queue"
]]></programlisting>
<para>The routing key is in fact a default value associated with
the particular channel. Outgoing messages can always have their
routing key uniquely set.</para>
<para>If the respective queue or exchange doesn't exist, an exception
is thrown when opening the channel. Queues and exchanges can be
created and configured using qpid-config.</para>
</section>
<section>
<title>Message Headers</title>
<para>AMQP specific message headers can be set on or retrieved
from the ServiceModel.Channels.Message using the AmqpProperties
type.</para>
<para>For example, on output:</para>
<programlisting><![CDATA[
AmqpProperties props = new AmqpProperties();
props.Durable = true;
props.PropertyMap.Add("my_custom_header", new AmqpString("a custom value"));
Message msg = Message.CreateMessage(args);
msg.Properties.Add("AmqpProperties", amqpProperties);
outputChannel.Send(msg);
]]></programlisting>
<para>On input the headers can be accessed from the Message or extracted
from the operation context</para>
<programlisting><![CDATA[
public void SayHello(string greeting)
{
AmqpProperties props = (AmqpProperties) OperationContext.
Current.IncomingMessageProperties["AmqpProperties"];
AmqpString extra = (AmqpString) props.PropertyMap["my_custom_header"];
Console.WriteLine("Service received: {0} and {1}", greeting, extra);
}
]]></programlisting>
</section>
<section>
<title>Security</title>
<para>To engage TLS/SSL:</para>
<programlisting><![CDATA[
binding.Security.Mode = AmqpSecurityMode.Transport;
binding.Security.Transport.UseSSL = true;
binding.BrokerPort = 5671;
]]></programlisting>
<para>Currently the WCF client only provides SASL PLAIN (i.e. username and
password) authentication. To provide a username and password, you can
set the DefaultAmqpCredential value in the binding. This value can be
overridden or set for a binding's channel factories and listeners,
either by setting the ClientCredentials as a binding parameter, or by
using an AmqpCredential as a binding parameter. The search order for
credentials is the AmqpCredential binding parameter, followed by the
ClientCredentials (unless IgnoreEndpointClientCredentials has been
set), and finally defaulting to the DefaultAmqpCredential of the
binding itself. Here is a sample using ClientCredentials:</para>
<programlisting><![CDATA[
ClientCredentials credentials = new ClientCredentials();
credentials.UserName.UserName = "guest";
credentials.UserName.Password = "guest";
bindingParameters = new BindingParameterCollection();
bindingParameters.Add(credentials);
readerFactory = binding.BuildChannelFactory<IInputChannel>(bindingParameters);
]]></programlisting>
</section>
<section>
<title>Transactions</title>
<para>The WCF channel provides a transaction resource manager
module and a recovery module that together provide distributed
transaction support with one-phase optimization. Some
configuration is required on Windows machines to enable
transaction support (see your installation notes or top level
ReadMe.txt file for instructions). Once properly configured,
the Qpid WCF channel acts as any other System.Transactions aware
resource, capable of participating in explicit or implicit
transactions.</para>
<para>Server code:</para>
<programlisting><![CDATA[
[OperationBehavior(TransactionScopeRequired = true,
TransactionAutoComplete = true)]
public void SayHello(string greeting)
{
// increment ExactlyOnceReceived counter on DB
// Success: transaction auto completes:
}
]]></programlisting>
<para>Because this operation involves two transaction resources, the
database and the AMQP message broker, this operates as a full two
phase commit transaction managed by the Distributed Transaction
Coordinator service. If the transaction proceeds without error,
both ExactlyOnceReceived is incremented in the database and the AMQP
message is consumed from the broker. Otherwise, ExactlyOnceReceived is
unchanged and AMQP message is returned to its queue on the broker.</para>
<para>For the client code a few changes are made to the non-transacted
example. For "exactly once" semantics, we set the AMQP "Durable"
message property and enclose the transacted activities in a
TransactionScope:</para>
<programlisting><![CDATA[
AmqpProperties myDefaults = new AmqpProperties();
myDefaults.Durable = true;
amqpBinding.DefaultMessageProperties = myDefaults;
ChannelFactory<IHelloService> channelFactory =
new ChannelFactory<IHelloService>(amqpBinding, clientEndpoint);
IHelloService clientProxy = channelFactory.CreateChannel();
using (TransactionScope ts = new TransactionScope())
{
AmqpProperties amqpProperties = new AmqpProperties();
clientProxy.SayHello("Greetings from WCF client");
// increment ExactlyOnceSent counter on DB
ts.Complete();
}
]]></programlisting>
</section>
</chapter>
<chapter>
<title>The .NET Binding for the C++ Messaging Client</title>
<para>
The .NET Binding for the C++ Qpid Messaging Client is a library that gives
any .NET program access to Qpid C++ Messaging objects and methods.
</para>
<section>
<title>.NET Binding for the C++ Messaging Client Component Architecture</title>
<programlisting><![CDATA[
+----------------------------+
| Dotnet examples |
| Managed C# |
+------+---------------+-----+
| |
V |
+---------------------------+ |
| .NET Managed Callback | |
| org.apache.qpid.messaging.| |
| sessionreceiver.dll | |
+----------------------+----+ |
| |
managed V V
(.NET) +--------------------------------+
:::::::::::::::::::::::| .NET Binding Library |::::::::::::
unmanaged | org.apache.qpid.messaging.dll |
(Native Win32/64) +---------------+----------------+
|
|
+----------------+ |
| Native examples| |
| Unmanaged C++ | |
+--------+-------+ |
| |
V V
+----------------------------------+
| QPID Messaging C++ Libraries |
| qpid*.dll qmf*.dll |
+--------+--------------+----------+
]]></programlisting>
<para>This diagram illustrates the code and library components of the binding
and the hierarchical relationships between them.</para>
<table id="table-Dotnet-Binding-Component-Architecture" >
<title>.NET Binding for the C++ Messaging Client Component Architecture</title>
<tgroup cols="2">
<thead>
<row>
<entry>Component Name</entry>
<entry>Component Function</entry>
</row>
</thead>
<tbody>
<row>
<entry>QPID Messaging C++ Libraries</entry>
<entry>The QPID Messaging C++ core run time system</entry>
</row>
<row>
<entry>Unmanaged C++ Example Source Programs</entry>
<entry>Ordinary C++ programs that illustrate using qpid/cpp Messaging directly
in a native Windows environment.</entry>
</row>
<row>
<entry>.NET Messaging Binding Library</entry>
<entry>The .NET Messaging Binding library provides interoprability between
managed .NET programs and the unmanaged, native Qpid Messaging C++ core
run time system. .NET programs create a Reference to this library thereby
exposing all of the native C++ Messaging functionality to programs
written in any .NET language.</entry>
</row>
<row>
<entry>.NET Messaging Managed Callback Library</entry>
<entry>An extension of the .NET Messaging Binding Library that provides message
callbacks in a managed .NET environment.</entry>
</row>
<row>
<entry>Managed C# .NET Example Source Programs</entry>
<entry>Various C# example programs that illustrate using .NET Binding for C++ Messaging in the .NET environment.</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding for the C++ Messaging Client Examples</title>
<para>This chapter describes the various sample programs that
are available to illustrate common Qpid Messaging usage.</para>
<table id="table-Dotnet-Binding-Example-Client-Server">
<title>Example : Client - Server</title>
<tgroup cols="2">
<colspec colname="c1"/>
<colspec colname="c2"/>
<thead>
<row>
<entry>Example Name</entry>
<entry>Example Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>csharp.example.server</entry>
<entry>Creates a Receiver and listens for messages.
Upon message reception the message content is converted to upper case
and forwarded to the received message's ReplyTo address.</entry>
</row>
<row>
<entry>csharp.example.client</entry>
<entry>Sends a series of messages to the Server and prints the original message
content and the received message content.</entry>
</row>
</tbody>
</tgroup>
</table>
<table id="table-Dotnet-Binding-Example-MapSender-MapReceiver">
<title>Example : Map Sender – Map Receiver</title>
<tgroup cols="2">
<colspec colname="c1"/>
<colspec colname="c2"/>
<thead>
<row>
<entry>Example Name</entry>
<entry>Example Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>csharp.map.receiver</entry>
<entry>Creates a Receiver and listens for a map message.
Upon message reception the message is decoded and displayed on the console.</entry>
</row>
<row>
<entry>csharp.map.sender</entry>
<entry>Creates a map message and sends it to map.receiver.
The map message contains values for every supported .NET Messaging
Binding data type.</entry>
</row>
</tbody>
</tgroup>
</table>
<table id="table-Dotnet-Binding-Example-Spout-Drain">
<title>Example : Spout - Drain</title>
<tgroup cols="2">
<colspec colname="c1"/>
<colspec colname="c2"/>
<thead>
<row>
<entry>Example Name</entry>
<entry>Example Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>csharp.example.spout</entry>
<entry>Spout is a more complex example of code that generates a series of messages
and sends them to peer program Drain. Flexible command line arguments allow
the user to specify a variety of message and program options.</entry>
</row>
<row>
<entry>csharp.example.drain</entry>
<entry>Drain is a more complex example of code that receives a series of messages
and displays their contents on the console.</entry>
</row>
</tbody>
</tgroup>
</table>
<table id="table-Dotnet-Binding-Example-CallbackSender-CallbackReceiver">
<title>Example : Map Callback Sender – Map Callback Receiver</title>
<tgroup cols="2">
<colspec colname="c1"/>
<colspec colname="c2"/>
<thead>
<row>
<entry>Example Name</entry>
<entry>Example Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>csharp.map.callback.receiver</entry>
<entry>Creates a Receiver and listens for a map message.
Upon message reception the message is decoded and displayed on the console.
This example illustrates the use of the C# managed code callback mechanism
provided by .NET Messaging Binding Managed Callback Library.</entry>
</row>
<row>
<entry>csharp.map.callback.sender</entry>
<entry>Creates a map message and sends it to map_receiver.
The map message contains values for every supported .NET Messaging
Binding data type.</entry>
</row>
</tbody>
</tgroup>
</table>
<table id="table-Dotnet-Binding-Example-DeclareQueues">
<title>Example - Declare Queues</title>
<tgroup cols="2">
<colspec colname="c1"/>
<colspec colname="c2"/>
<thead>
<row>
<entry>Example Name</entry>
<entry>Example Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>csharp.example.declare_queues</entry>
<entry>A program to illustrate creating objects on a broker.
This program creates a queue used by spout and drain.</entry>
</row>
</tbody>
</tgroup>
</table>
<table id="table-Dotnet-Binding-Example-DirectSender-DirectReceiver">
<title>Example: Direct Sender - Direct Receiver</title>
<tgroup cols="2">
<colspec colname="c1"/>
<colspec colname="c2"/>
<thead>
<row>
<entry>Example Name</entry>
<entry>Example Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>csharp.direct.receiver</entry>
<entry>Creates a Receiver and listens for a messages.
Upon message reception the message is decoded and displayed on the console.</entry>
</row>
<row>
<entry>csharp.direct.sender</entry>
<entry> Creates a series of messages and sends them to csharp.direct.receiver.</entry>
</row>
</tbody>
</tgroup>
</table>
<table id="table-Dotnet-Binding-Example-Helloworld">
<title>Example: Hello World</title>
<tgroup cols="2">
<colspec colname="c1"/>
<colspec colname="c2"/>
<thead>
<row>
<entry>Example Name</entry>
<entry>Example Description</entry>
</row>
</thead>
<tbody>
<row>
<entry>csharp.example.helloworld</entry>
<entry>A program to send a message and to receive the same message.</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding Class Mapping to Underlying C++ Messaging API</title>
<para>This chapter describes the specific mappings between
classes in the .NET Binding and the underlying C++ Messaging
API.</para>
<section>
<title>.NET Binding for the C++ Messaging API Class: Address</title>
<table id="table-Dotnet-Binding-Address">
<title>.NET Binding for the C++ Messaging API Class: Address</title>
<tgroup cols="2">
<colspec colname="c1" colwidth="1*"/>
<colspec colname="c2" colwidth="7*"/>
<thead>
<row>
<entry namest="c1" nameend="c2" align="center">.NET Binding Class: Address</entry>
</row>
<row>
<entry>Language</entry>
<entry>Syntax</entry>
</row>
</thead>
<tbody>
<row>
<entry>C++</entry>
<entry>class Address</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ref class Address</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Address();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Address();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Address(const std::string&amp; address);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Address(string address);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Address(const std::string&amp; name, const std::string&amp; subject, const qpid::types::Variant::Map&amp; options, const std::string&amp; type = "");</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Address(string name, string subject, Dictionary&lt;string, object&gt; options);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Address(string name, string subject, Dictionary&lt;string, object&gt; options, string type);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Address(const Address&amp; address);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Address(Address address);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Destructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>~Address();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>~Address();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Finalizer</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>!Address();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy assignment operator</entry>
</row>
<row>
<entry>C++</entry>
<entry>Address&amp; operator=(const Address&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Address op_Assign(Address rhs);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Name</entry>
</row>
<row>
<entry>C++</entry>
<entry>const std::string&amp; getName() const;</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setName(const std::string&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string Name { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Subject</entry>
</row>
<row>
<entry>C++</entry>
<entry>const std::string&amp; getSubject() const;</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setSubject(const std::string&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string Subject { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Options</entry>
</row>
<row>
<entry>C++</entry>
<entry>const qpid::types::Variant::Map&amp; getOptions() const;</entry>
</row>
<row>
<entry>C++</entry>
<entry>qpid::types::Variant::Map&amp; getOptions();</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setOptions(const qpid::types::Variant::Map&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Dictionary&lt;string, object&gt; Options { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Type</entry>
</row>
<row>
<entry>C++</entry>
<entry>std::string getType() const;</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setType(const std::string&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string Type { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Miscellaneous</entry>
</row>
<row>
<entry>C++</entry>
<entry>std::string str() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string ToStr();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Miscellaneous</entry>
</row>
<row>
<entry>C++</entry>
<entry>operator bool() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>n/a</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Miscellaneous</entry>
</row>
<row>
<entry>C++</entry>
<entry>bool operator !() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>n/a</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding for the C++ Messaging API Class: Connection</title>
<table id="table-Dotnet-Binding-Connection">
<title>.NET Binding for the C++ Messaging API Class: Connection</title>
<tgroup cols="2">
<colspec colname="c1" colwidth="1*"/>
<colspec colname="c2" colwidth="7*"/>
<thead>
<row>
<entry namest="c1" nameend="c2" align="center">.NET Binding Class: Connection</entry>
</row>
<row>
<entry>Language</entry>
<entry>Syntax</entry>
</row>
</thead>
<tbody>
<row>
<entry>C++</entry>
<entry>class Connection : public qpid::messaging::Handle&lt;ConnectionImpl&gt;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ref class Connection</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Connection(ConnectionImpl* impl);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>n/a</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Connection();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>n/a</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Connection(const std::string&amp; url, const qpid::types::Variant::Map&amp; options = qpid::types::Variant::Map());</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Connection(string url);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Connection(string url, Dictionary&lt;string, object&gt; options);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Connection(const std::string&amp; url, const std::string&amp; options);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Connection(string url, string options); </entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Connection(const Connection&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Connection(Connection connection);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Destructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>~Connection();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>~Connection();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Finalizer</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>!Connection();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy assignment operator</entry>
</row>
<row>
<entry>C++</entry>
<entry>Connection&amp; operator=(const Connection&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Connection op_Assign(Connection rhs);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: SetOption</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setOption(const std::string&amp; name, const qpid::types::Variant&amp; value);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void SetOption(string name, object value);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: open</entry>
</row>
<row>
<entry>C++</entry>
<entry>void open();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Open();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: isOpen</entry>
</row>
<row>
<entry>C++</entry>
<entry>bool isOpen();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool IsOpen { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: close</entry>
</row>
<row>
<entry>C++</entry>
<entry>void close();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Close();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: createTransactionalSession</entry>
</row>
<row>
<entry>C++</entry>
<entry>Session createTransactionalSession(const std::string&amp; name = std::string());</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Session CreateTransactionalSession();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Session CreateTransactionalSession(string name);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: createSession</entry>
</row>
<row>
<entry>C++</entry>
<entry>Session createSession(const std::string&amp; name = std::string());</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Session CreateSession();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Session CreateSession(string name);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: getSession</entry>
</row>
<row>
<entry>C++</entry>
<entry>Session getSession(const std::string&amp; name) const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Session GetSession(string name);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: AuthenticatedUsername</entry>
</row>
<row>
<entry>C++</entry>
<entry>std::string getAuthenticatedUsername();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string GetAuthenticatedUsername();</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding for the C++ Messaging API Class: Duration</title>
<table id="table-Dotnet-Binding-Duration">
<title>.NET Binding for the C++ Messaging API Class: Duration</title>
<tgroup cols="2">
<colspec colname="c1" colwidth="1*"/>
<colspec colname="c2" colwidth="7*"/>
<thead>
<row>
<entry namest="c1" nameend="c2" align="center">.NET Binding Class: Duration</entry>
</row>
<row>
<entry>Language</entry>
<entry>Syntax</entry>
</row>
</thead>
<tbody>
<row>
<entry>C++</entry>
<entry>class Duration</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ref class Duration</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>explicit Duration(uint64_t milliseconds);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Duration(ulong mS);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Duration(Duration rhs);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Destructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>default</entry>
</row>
<row>
<entry>.NET</entry>
<entry>default</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Finalizer</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>default</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Milliseconds</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint64_t getMilliseconds() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ulong Milliseconds { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Operator: *</entry>
</row>
<row>
<entry>C++</entry>
<entry>Duration operator*(const Duration&amp; duration, uint64_t multiplier);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public static Duration operator *(Duration dur, ulong multiplier);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public static Duration Multiply(Duration dur, ulong multiplier);</entry>
</row>
<row>
<entry>C++</entry>
<entry>Duration operator*(uint64_t multiplier, const Duration&amp; duration);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public static Duration operator *(ulong multiplier, Duration dur);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public static Duration Multiply(ulong multiplier, Duration dur);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constants</entry>
</row>
<row>
<entry>C++</entry>
<entry>static const Duration FOREVER;</entry>
</row>
<row>
<entry>C++</entry>
<entry>static const Duration IMMEDIATE;</entry>
</row>
<row>
<entry>C++</entry>
<entry>static const Duration SECOND;</entry>
</row>
<row>
<entry>C++</entry>
<entry>static const Duration MINUTE;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public sealed class DurationConstants</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public static Duration FORVER;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public static Duration IMMEDIATE;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public static Duration MINUTE;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public static Duration SECOND;</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding for the C++ Messaging API Class: FailoverUpdates</title>
<table id="table-Dotnet-Binding-FailoverUpdates">
<title>.NET Binding for the C++ Messaging API Class: FailoverUpdates</title>
<tgroup cols="2">
<colspec colname="c1" colwidth="1*"/>
<colspec colname="c2" colwidth="7*"/>
<thead>
<row>
<entry namest="c1" nameend="c2" align="center">.NET Binding Class: FailoverUpdates</entry>
</row>
<row>
<entry>Language</entry>
<entry>Syntax</entry>
</row>
</thead>
<tbody>
<row>
<entry>C++</entry>
<entry>class FailoverUpdates</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ref class FailoverUpdates</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>FailoverUpdates(Connection&amp; connection);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public FailoverUpdates(Connection connection);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Destructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>~FailoverUpdates();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>~FailoverUpdates();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Finalizer</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>!FailoverUpdates();</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding for the C++ Messaging API Class: Message</title>
<table id="table-Dotnet-Binding-Message">
<title>.NET Binding for the C++ Messaging API Class: Message</title>
<tgroup cols="2">
<colspec colname="c1" colwidth="1*"/>
<colspec colname="c2" colwidth="7*"/>
<thead>
<row>
<entry namest="c1" nameend="c2" align="center">.NET Binding Class: Message</entry>
</row>
<row>
<entry>Language</entry>
<entry>Syntax</entry>
</row>
</thead>
<tbody>
<row>
<entry>C++</entry>
<entry>class Message</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ref class Message</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Message(const std::string&amp; bytes = std::string());</entry>
</row>
<row>
<entry>.NET</entry>
<entry>Message();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>Message(System::String ^ theStr);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>Message(System::Object ^ theValue);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>Message(array&lt;System::Byte&gt; ^ bytes);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Message(const char*, size_t);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Message(byte[] bytes, int offset, int size);</entry>
</row>
<row>
<entry> </entry>
<entry>Copy constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Message(const Message&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Message(Message message);</entry>
</row>
<row>
<entry> </entry>
<entry>Copy assignment operator</entry>
</row>
<row>
<entry>C++</entry>
<entry>Message&amp; operator=(const Message&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Message op_Assign(Message rhs);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Destructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>~Message();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>~Message();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Finalizer</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>!Message()</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: ReplyTo</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setReplyTo(const Address&amp;);</entry>
</row>
<row>
<entry>C++</entry>
<entry>const Address&amp; getReplyTo() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Address ReplyTo { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Subject</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setSubject(const std::string&amp;);</entry>
</row>
<row>
<entry>C++</entry>
<entry>const std::string&amp; getSubject() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string Subject { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: ContentType</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setContentType(const std::string&amp;);</entry>
</row>
<row>
<entry>C++</entry>
<entry>const std::string&amp; getContentType() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string ContentType { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: MessageId</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setMessageId(const std::string&amp;);</entry>
</row>
<row>
<entry>C++</entry>
<entry>const std::string&amp; getMessageId() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string MessageId { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: UserId</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setUserId(const std::string&amp;);</entry>
</row>
<row>
<entry>C++</entry>
<entry>const std::string&amp; getUserId() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string UserId { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: CorrelationId</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setCorrelationId(const std::string&amp;);</entry>
</row>
<row>
<entry>C++</entry>
<entry>const std::string&amp; getCorrelationId() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string CorrelationId { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Priority</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setPriority(uint8_t);</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint8_t getPriority() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public byte Priority { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Ttl</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setTtl(Duration ttl);</entry>
</row>
<row>
<entry>C++</entry>
<entry>Duration getTtl() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Duration Ttl { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Durable</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setDurable(bool durable);</entry>
</row>
<row>
<entry>C++</entry>
<entry>bool getDurable() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool Durable { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Redelivered</entry>
</row>
<row>
<entry>C++</entry>
<entry>bool getRedelivered() const;</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setRedelivered(bool);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool Redelivered { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: SetProperty</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setProperty(const std::string&amp;, const qpid::types::Variant&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void SetProperty(string name, object value);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Properties</entry>
</row>
<row>
<entry>C++</entry>
<entry>const qpid::types::Variant::Map&amp; getProperties() const;</entry>
</row>
<row>
<entry>C++</entry>
<entry>qpid::types::Variant::Map&amp; getProperties();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Dictionary&lt;string, object&gt; Properties { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: SetContent</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setContent(const std::string&amp;);</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setContent(const char* chars, size_t count);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void SetContent(byte[] bytes);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void SetContent(string content);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void SetContent(byte[] bytes, int offset, int size);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: GetContent</entry>
</row>
<row>
<entry>C++</entry>
<entry>std::string getContent() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string GetContent();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void GetContent(byte[] arr);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void GetContent(Collection&lt;object&gt; __p1);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void GetContent(Dictionary&lt;string, object&gt; dict);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: GetContentPtr</entry>
</row>
<row>
<entry>C++</entry>
<entry>const char* getContentPtr() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>n/a</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: ContentSize</entry>
</row>
<row>
<entry>C++</entry>
<entry>size_t getContentSize() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ulong ContentSize { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Struct: EncodingException</entry>
</row>
<row>
<entry>C++</entry>
<entry>struct EncodingException : qpid::types::Exception</entry>
</row>
<row>
<entry>.NET</entry>
<entry>n/a</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: decode</entry>
</row>
<row>
<entry>C++</entry>
<entry>void decode(const Message&amp; message, qpid::types::Variant::Map&amp; map, const std::string&amp; encoding = std::string());</entry>
</row>
<row>
<entry>C++</entry>
<entry>void decode(const Message&amp; message, qpid::types::Variant::List&amp; list, const std::string&amp; encoding = std::string());</entry>
</row>
<row>
<entry>.NET</entry>
<entry>n/a</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: encode</entry>
</row>
<row>
<entry>C++</entry>
<entry>void encode(const qpid::types::Variant::Map&amp; map, Message&amp; message, const std::string&amp; encoding = std::string());</entry>
</row>
<row>
<entry>C++</entry>
<entry>void encode(const qpid::types::Variant::List&amp; list, Message&amp; message, const std::string&amp; encoding = std::string());</entry>
</row>
<row>
<entry>.NET</entry>
<entry>n/a</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: AsString</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string AsString(object obj);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string ListAsString(Collection&lt;object&gt; list);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string MapAsString(Dictionary&lt;string, object&gt; dict);</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding for the C++ Messaging API Class: Receiver</title>
<table id="table-Dotnet-Binding-Receiver">
<title>.NET Binding for the C++ Messaging API Class: Receiver</title>
<tgroup cols="2">
<colspec colname="c1" colwidth="1*"/>
<colspec colname="c2" colwidth="7*"/>
<thead>
<row>
<entry namest="c1" nameend="c2" align="center">.NET Binding Class: Receiver</entry>
</row>
<row>
<entry>Language</entry>
<entry>Syntax</entry>
</row>
</thead>
<tbody>
<row>
<entry>C++</entry>
<entry>class Receiver</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ref class Receiver</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>.NET</entry>
<entry>Constructed object is returned by Session.CreateReceiver</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Receiver(const Receiver&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Receiver(Receiver receiver);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Destructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>~Receiver();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>~Receiver();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Finalizer</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>!Receiver()</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy assignment operator</entry>
</row>
<row>
<entry>C++</entry>
<entry>Receiver&amp; operator=(const Receiver&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Receiver op_Assign(Receiver rhs);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Get</entry>
</row>
<row>
<entry>C++</entry>
<entry>bool get(Message&amp; message, Duration timeout=Duration::FOREVER);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool Get(Message mmsgp);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool Get(Message mmsgp, Duration durationp);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Get</entry>
</row>
<row>
<entry>C++</entry>
<entry>Message get(Duration timeout=Duration::FOREVER);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Message Get();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Message Get(Duration durationp);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Fetch</entry>
</row>
<row>
<entry>C++</entry>
<entry>bool fetch(Message&amp; message, Duration timeout=Duration::FOREVER);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool Fetch(Message mmsgp);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool Fetch(Message mmsgp, Duration duration);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Fetch</entry>
</row>
<row>
<entry>C++</entry>
<entry>Message fetch(Duration timeout=Duration::FOREVER);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Message Fetch();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Message Fetch(Duration durationp);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Capacity</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setCapacity(uint32_t);</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint32_t getCapacity();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public uint Capacity { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Available</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint32_t getAvailable();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public uint Available { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Unsettled</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint32_t getUnsettled();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public uint Unsettled { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Close</entry>
</row>
<row>
<entry>C++</entry>
<entry>void close();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Close();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: IsClosed</entry>
</row>
<row>
<entry>C++</entry>
<entry>bool isClosed() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool IsClosed { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Name</entry>
</row>
<row>
<entry>C++</entry>
<entry>const std::string&amp; getName() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string Name { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Session</entry>
</row>
<row>
<entry>C++</entry>
<entry>Session getSession() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Session Session { get; }</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding for the C++ Messaging API Class: Sender</title>
<table id="table-Dotnet-Binding-Sender">
<title>.NET Binding for the C++ Messaging API Class: Sender</title>
<tgroup cols="2">
<colspec colname="c1" colwidth="1*"/>
<colspec colname="c2" colwidth="7*"/>
<thead>
<row>
<entry namest="c1" nameend="c2" align="center">.NET Binding Class: Sender</entry>
</row>
<row>
<entry>Language</entry>
<entry>Syntax</entry>
</row>
</thead>
<tbody>
<row>
<entry>C++</entry>
<entry>class Sender</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ref class Sender</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>.NET</entry>
<entry>Constructed object is returned by Session.CreateSender</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Sender(const Sender&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Sender(Sender sender);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Destructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>~Sender();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>~Sender();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Finalizer</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>!Sender()</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy assignment operator</entry>
</row>
<row>
<entry>C++</entry>
<entry>Sender&amp; operator=(const Sender&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Sender op_Assign(Sender rhs);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Send</entry>
</row>
<row>
<entry>C++</entry>
<entry>void send(const Message&amp; message, bool sync=false);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Send(Message mmsgp);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Send(Message mmsgp, bool sync);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Close</entry>
</row>
<row>
<entry>C++</entry>
<entry>void close();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Close();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Capacity</entry>
</row>
<row>
<entry>C++</entry>
<entry>void setCapacity(uint32_t);</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint32_t getCapacity();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public uint Capacity { get; set; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Available</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint32_t getAvailable();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public uint Available { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Unsettled</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint32_t getUnsettled();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public uint Unsettled { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Name</entry>
</row>
<row>
<entry>C++</entry>
<entry>const std::string&amp; getName() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public string Name { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Session</entry>
</row>
<row>
<entry>C++</entry>
<entry>Session getSession() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Session Session { get; }</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding for the C++ Messaging API Class: Session</title>
<table id="table-Dotnet-Binding-Session">
<title>.NET Binding for the C++ Messaging API Class: Session</title>
<tgroup cols="2">
<colspec colname="c1" colwidth="1*"/>
<colspec colname="c2" colwidth="7*"/>
<thead>
<row>
<entry namest="c1" nameend="c2" align="center">.NET Binding Class: Session</entry>
</row>
<row>
<entry>Language</entry>
<entry>Syntax</entry>
</row>
</thead>
<tbody>
<row>
<entry>C++</entry>
<entry>class Session</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public ref class Session</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Constructor</entry>
</row>
<row>
<entry>.NET</entry>
<entry>Constructed object is returned by Connection.CreateSession</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy constructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>Session(const Session&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Session(Session session);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Destructor</entry>
</row>
<row>
<entry>C++</entry>
<entry>~Session();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>~Session();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Finalizer</entry>
</row>
<row>
<entry>C++</entry>
<entry>n/a</entry>
</row>
<row>
<entry>.NET</entry>
<entry>!Session()</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Copy assignment operator</entry>
</row>
<row>
<entry>C++</entry>
<entry>Session&amp; operator=(const Session&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Session op_Assign(Session rhs);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Close</entry>
</row>
<row>
<entry>C++</entry>
<entry>void close();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Close();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Commit</entry>
</row>
<row>
<entry>C++</entry>
<entry>void commit();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Commit();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Rollback</entry>
</row>
<row>
<entry>C++</entry>
<entry>void rollback();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Rollback();</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Acknowledge</entry>
</row>
<row>
<entry>C++</entry>
<entry>void acknowledge(bool sync=false);</entry>
</row>
<row>
<entry>C++</entry>
<entry>void acknowledge(Message&amp;, bool sync=false);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Acknowledge();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Acknowledge(bool sync);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Acknowledge(Message __p1);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Acknowledge(Message __p1, bool __p2);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Reject</entry>
</row>
<row>
<entry>C++</entry>
<entry>void reject(Message&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Reject(Message __p1);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Release</entry>
</row>
<row>
<entry>C++</entry>
<entry>void release(Message&amp;);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Release(Message __p1);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: Sync</entry>
</row>
<row>
<entry>C++</entry>
<entry>void sync(bool block=true);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Sync();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void Sync(bool block);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Receivable</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint32_t getReceivable();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public uint Receivable { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: UnsettledAcks</entry>
</row>
<row>
<entry>C++</entry>
<entry>uint32_t getUnsettledAcks();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public uint UnsetledAcks { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: NextReceiver</entry>
</row>
<row>
<entry>C++</entry>
<entry>bool nextReceiver(Receiver&amp;, Duration timeout=Duration::FOREVER);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool NextReceiver(Receiver rcvr);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool NextReceiver(Receiver rcvr, Duration timeout);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: NextReceiver</entry>
</row>
<row>
<entry>C++</entry>
<entry>Receiver nextReceiver(Duration timeout=Duration::FOREVER);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Receiver NextReceiver();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Receiver NextReceiver(Duration timeout);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: CreateSender</entry>
</row>
<row>
<entry>C++</entry>
<entry>Sender createSender(const Address&amp; address);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Sender CreateSender(Address address);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: CreateSender</entry>
</row>
<row>
<entry>C++</entry>
<entry>Sender createSender(const std::string&amp; address);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Sender CreateSender(string address);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: CreateReceiver</entry>
</row>
<row>
<entry>C++</entry>
<entry>Receiver createReceiver(const Address&amp; address);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Receiver CreateReceiver(Address address);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: CreateReceiver</entry>
</row>
<row>
<entry>C++</entry>
<entry>Receiver createReceiver(const std::string&amp; address);</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Receiver CreateReceiver(string address);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: GetSender</entry>
</row>
<row>
<entry>C++</entry>
<entry>Sender getSender(const std::string&amp; name) const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Sender GetSender(string name);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: GetReceiver</entry>
</row>
<row>
<entry>C++</entry>
<entry>Receiver getReceiver(const std::string&amp; name) const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Receiver GetReceiver(string name);</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: Connection</entry>
</row>
<row>
<entry>C++</entry>
<entry>Connection getConnection() const;</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public Connection Connection { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Property: HasError</entry>
</row>
<row>
<entry>C++</entry>
<entry>bool hasError();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public bool HasError { get; }</entry>
</row>
<row>
<entry namest="c1" nameend="c2" align="center">Method: CheckError</entry>
</row>
<row>
<entry>C++</entry>
<entry>void checkError();</entry>
</row>
<row>
<entry>.NET</entry>
<entry>public void CheckError();</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
<section>
<title>.NET Binding Class: SessionReceiver</title>
<para>
The SessionReceiver class provides a convenient callback
mechanism for Messages received by all Receivers on a given
Session.
</para>
<para>
<programlisting><![CDATA[
using Org.Apache.Qpid.Messaging;
using System;
namespace Org.Apache.Qpid.Messaging.SessionReceiver
{
public interface ISessionReceiver
{
void SessionReceiver(Receiver receiver, Message message);
}
public class CallbackServer
{
public CallbackServer(Session session, ISessionReceiver callback);
public void Close();
}
}
]]>
</programlisting>
</para>
<para>
To use this class a client program includes references to both
Org.Apache.Qpid.Messaging and Org.Apache.Qpid.Messaging.SessionReceiver.
The calling program creates a function that implements the
ISessionReceiver interface. This function will be called whenever
message is received by the session. The callback process is started
by creating a CallbackServer and will continue to run until the
client program calls the CallbackServer.Close function.
</para>
<para>
A complete operating example of using the SessionReceiver callback
is contained in cpp/bindings/qpid/dotnet/examples/csharp.map.callback.receiver.
</para>
</section>
</section>
</chapter>
</book>
<!--
- client code remains exactly the same, but routing behavior
changes
- exchanges drop messages if nobody is listening, so we need to
start drain first
- drain will exit immediately if the source is empty (note that
this is actually a semantic guarantee provided by the API, we
know for a fact that the source is empty when drain/fetch
reports it, no fudge factor timeout is required [this assumes
nobody is concurrently publishing of course])
- drain -f invokes blocking fetch (you could use a timeout here also)
-->