docs/components/modules/ROOT/pages/aws-sns-component.adoc

[[aws-sns-component]]
= AWS Simple Notification System Component
:page-source: components/camel-aws-sns/src/main/docs/aws-sns-component.adoc

*Available as of Camel version 2.8*

The SNS component allows messages to be sent to an
https://aws.amazon.com/sns[Amazon Simple Notification] Topic. The
implementation of the Amazon API is provided by
the https://aws.amazon.com/sdkforjava/[AWS SDK].

Prerequisites

You must have a valid Amazon Web Services developer account, and be
signed up to use Amazon SNS. More information is available at
https://aws.amazon.com/sns[Amazon SNS].

== URI Format

[source,java]
-----------------------------
aws-sns://topicNameOrArn[?options]
-----------------------------

The topic will be created if they don't already exists. +
 You can append query options to the URI in the following format,
`?options=value&option2=value&...`

== URI Options


// component options: START
The AWS Simple Notification System component supports 5 options, which are listed below.



[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *configuration* (advanced) | The AWS SNS default configuration |  | SnsConfiguration
| *accessKey* (producer) | Amazon AWS Access Key |  | String
| *secretKey* (producer) | Amazon AWS Secret Key |  | String
| *region* (producer) | The region in which SNS client needs to work |  | String
| *basicPropertyBinding* (advanced) | Whether the component should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities | false | boolean
|===
// component options: END





// endpoint options: START
The AWS Simple Notification System endpoint is configured using URI syntax:

----
aws-sns:topicNameOrArn
----

with the following path and query parameters:

=== Path Parameters (1 parameters):


[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *topicNameOrArn* | *Required* Topic name or ARN |  | String
|===


=== Query Parameters (19 parameters):


[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *amazonSNSClient* (producer) | To use the AmazonSNS as the client |  | AmazonSNS
| *amazonSQSClient* (producer) | An SQS Client to use as bridge between SNS and SQS |  | AmazonSQS
| *autoCreateTopic* (producer) | Setting the autocreation of the topic | true | boolean
| *headerFilterStrategy* (producer) | To use a custom HeaderFilterStrategy to map headers to/from Camel. |  | HeaderFilterStrategy
| *kmsMasterKeyId* (producer) | The ID of an AWS-managed customer master key (CMK) for Amazon SNS or a custom CMK. |  | String
| *lazyStartProducer* (producer) | Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel's routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. | false | boolean
| *messageStructure* (producer) | The message structure to use such as json |  | String
| *policy* (producer) | The policy for this queue |  | String
| *proxyHost* (producer) | To define a proxy host when instantiating the SNS client |  | String
| *proxyPort* (producer) | To define a proxy port when instantiating the SNS client |  | Integer
| *queueUrl* (producer) | The queueUrl to subscribe to |  | String
| *region* (producer) | The region in which SNS client needs to work. When using this parameter, the configuration will expect the capitalized name of the region (for example AP_EAST_1) You'll need to use the name Regions.EU_WEST_1.name() |  | String
| *serverSideEncryptionEnabled* (producer) | Define if Server Side Encryption is enabled or not on the topic | false | boolean
| *subject* (producer) | The subject which is used if the message header 'CamelAwsSnsSubject' is not present. |  | String
| *subscribeSNStoSQS* (producer) | Define if the subscription between SNS Topic and SQS must be done or not | false | boolean
| *basicPropertyBinding* (advanced) | Whether the endpoint should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities | false | boolean
| *synchronous* (advanced) | Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). | false | boolean
| *accessKey* (security) | Amazon AWS Access Key |  | String
| *secretKey* (security) | Amazon AWS Secret Key |  | String
|===
// endpoint options: END
// spring-boot-auto-configure options: START
== Spring Boot Auto-Configuration

When using Spring Boot make sure to use the following Maven dependency to have support for auto configuration:

[source,xml]
----
<dependency>
  <groupId>org.apache.camel</groupId>
  <artifactId>camel-aws-sns-starter</artifactId>
  <version>x.x.x</version>
  <!-- use the same version as your Camel core version -->
</dependency>
----


The component supports 22 options, which are listed below.



[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *camel.component.aws-sns.access-key* | Amazon AWS Access Key |  | String
| *camel.component.aws-sns.basic-property-binding* | Whether the component should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities | false | Boolean
| *camel.component.aws-sns.configuration.access-key* | Amazon AWS Access Key |  | String
| *camel.component.aws-sns.configuration.amazon-s-n-s-client* | To use the AmazonSNS as the client |  | AmazonSNS
| *camel.component.aws-sns.configuration.amazon-s-q-s-client* | An SQS Client to use as bridge between SNS and SQS |  | AmazonSQS
| *camel.component.aws-sns.configuration.auto-create-topic* | Setting the autocreation of the topic | true | Boolean
| *camel.component.aws-sns.configuration.kms-master-key-id* | The ID of an AWS-managed customer master key (CMK) for Amazon SNS or a custom CMK. |  | String
| *camel.component.aws-sns.configuration.message-structure* | The message structure to use such as json |  | String
| *camel.component.aws-sns.configuration.policy* | The policy for this queue |  | String
| *camel.component.aws-sns.configuration.proxy-host* | To define a proxy host when instantiating the SNS client |  | String
| *camel.component.aws-sns.configuration.proxy-port* | To define a proxy port when instantiating the SNS client |  | Integer
| *camel.component.aws-sns.configuration.queue-url* | The queueUrl to subscribe to |  | String
| *camel.component.aws-sns.configuration.region* | The region in which SNS client needs to work. When using this parameter, the configuration will expect the capitalized name of the region (for example AP_EAST_1) You'll need to use the name Regions.EU_WEST_1.name() |  | String
| *camel.component.aws-sns.configuration.secret-key* | Amazon AWS Secret Key |  | String
| *camel.component.aws-sns.configuration.server-side-encryption-enabled* | Define if Server Side Encryption is enabled or not on the topic | false | Boolean
| *camel.component.aws-sns.configuration.subject* | The subject which is used if the message header 'CamelAwsSnsSubject' is not present. |  | String
| *camel.component.aws-sns.configuration.subscribe-s-n-sto-s-q-s* | Define if the subscription between SNS Topic and SQS must be done or not | false | Boolean
| *camel.component.aws-sns.configuration.topic-arn* | The Amazon Resource Name (ARN) assigned to the created topic. |  | String
| *camel.component.aws-sns.configuration.topic-name* | The name of the topic |  | String
| *camel.component.aws-sns.enabled* | Whether to enable auto configuration of the aws-sns component. This is enabled by default. |  | Boolean
| *camel.component.aws-sns.region* | The region in which SNS client needs to work |  | String
| *camel.component.aws-sns.secret-key* | Amazon AWS Secret Key |  | String
|===
// spring-boot-auto-configure options: END





Required SNS component options

You have to provide the amazonSNSClient in the
Registry or your accessKey and secretKey to access
the https://aws.amazon.com/sns[Amazon's SNS].

== Usage

=== Message headers evaluated by the SNS producer

[width="100%",cols="10%,10%,80%",options="header",]
|=======================================================================
|Header |Type |Description

|`CamelAwsSnsSubject` |`String` |The Amazon SNS message subject. If not set, the subject from the
`SnsConfiguration` is used.
|=======================================================================

=== Message headers set by the SNS producer

[width="100%",cols="10%,10%,80%",options="header",]
|=======================================================================
|Header |Type |Description

|`CamelAwsSnsMessageId` |`String` |The Amazon SNS message ID.
|=======================================================================

=== Advanced AmazonSNS configuration

If you need more control over the `AmazonSNS` instance configuration you
can create your own instance and refer to it from the URI:

[source,java]
-------------------------------------------------
from("direct:start")
.to("aws-sns://MyTopic?amazonSNSClient=#client");
-------------------------------------------------

The `#client` refers to a `AmazonSNS` in the
Registry.

For example if your Camel Application is running behind a firewall:

[source,java]
--------------------------------------------------------------------------------------
AWSCredentials awsCredentials = new BasicAWSCredentials("myAccessKey", "mySecretKey");
ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);
AmazonSNS client = new AmazonSNSClient(awsCredentials, clientConfiguration);

registry.bind("client", client);
--------------------------------------------------------------------------------------

=== Create a subscription between an AWS SNS Topic and an AWS SQS Queue

You can create a subscription of an SQS Queue to an SNS Topic in this way:

[source,java]
-------------------------------------------------
from("direct:start")
.to("aws-sns://test-camel-sns1?amazonSNSClient=#amazonSNSClient&amazonSQSClient=#amazonSQSClient&subscribeSNStoSQS=true&queueUrl=https://sqs.eu-central-1.amazonaws.com/780410022472/test-camel");
-------------------------------------------------

The `#amazonSNSClient` refers to a `AmazonSNS` in the
Registry, while the `#amazonSQSClient` refers to an `AmazonSQS` client.
By specifying `subscribeSNStoSQS` to true and a `queueUrl` of an existing SQS Queue,
you'll be able to subscribe your SQS Queue to your SNS Topic.

At this point you can consume messages coming from SNS Topic through your SQS Queue

[source,java]
-------------------------------------------------
from("aws-sqs://test-camel?amazonSQSClient=#amazonSQSClient&delay=50&maxMessagesPerPoll=5")
    .to(...);
-------------------------------------------------

== Topic Autocreation

With the option `autoCreateTopic` users are able to avoid the autocreation of an SNS Topic in case it doesn't exist. The default for this option is `true`.
If set to false any operation on a not-existent topic in AWS won't be successful and an error will be returned.

== Automatic detection of AmazonSNS client in registry

The component is capable of detecting the presence of an AmazonSNS bean into the registry.
If it's the only instance of that type it will be used as client and you won't have to define it as uri parameter.
This may be really useful for smarter configuration of the endpoint.

== Dependencies

Maven users will need to add the following dependency to their pom.xml.

*pom.xml*

[source,xml]
---------------------------------------
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-aws-sns</artifactId>
    <version>${camel-version}</version>
</dependency>
---------------------------------------

where `$\{camel-version\}` must be replaced by the actual version of Camel.