There are 3 Go packages for proton:
electron are alternative APIs for sending messages.
proton is a direct wrapping of the concurrent-unsafe, event-driven C proton API.
electron is a procedural, concurrent-safe interface that may be more convenient and familiar for Go programmers. The examples
electron/broker.go give an illustration of how the APIs differ.
If you have the proton C library and headers installed you can get the latest go packages with
go get qpid.apache.org/electron
If proton is installed in a non-standard place (other than /usr or /usr/local) you can set these environment variables before
go get, for example:
export CGO_LDFLAGS="-L/<my-proton>/lib" export CGO_CFLAGS="-I/<my-proton>/include" go get qpid.apache.org/electron
If you have a proton build you don't need to
go get, you can set your GOPATH to use the binding from the checkout with:
Once you are set up, the go tools will work as normal. You can see documentation in your web browser at
localhost:6060 by running:
You can run the examples directly from source like this:
go run <program>.go
This is a little slow (a couple of seconds) as it compiles the program and runs it in one step. You can compile the program first and then run the executable to avoid the delay:
go build <program>.go ./<program>
All the examples take a
-h flag to show usage information, and the comments in the example source have more details.
First start the broker (the optional
-debug flag will print extra information about what the broker is doing)
go run broker.go -debug
Send messages concurrently to queues “foo” and “bar”, 10 messages to each queue:
go run send.go -count 10 localhost:/foo localhost:/bar
Receive messages concurrently from “foo” and “bar”. Note -count 20 for 10 messages each on 2 queues:
go run receive.go -count 20 localhost:/foo localhost:/bar
The broker and clients use the standard AMQP port (5672) on the local host by default, to use a different address use the
-addr host:port flag.
If you have the full proton repository checked out you can try try using the python broker with Go clients:
Or use the Go broker and the python clients:
python ../python/simple_send.py python ../python/simple_recv.py
electron packages provide two alternate APIs for AMQP applications. See the proton Go README for a discussion of why there are two APIs.
electron/broker.go both implement the same simple broker-like functionality using each of the two APIs. They both handle multiple connections concurrently and store messages on bounded queues implemented by Go channels.
electron/broker is less than half as long as the
proton/broker illustrating why it is better suited for most Go applications.
proton/broker must explicitly handle proton events, which are processed in a single goroutine per connection since proton is not concurrent safe. Each connection uses channels to exchange messages between the event-handling goroutine and the shared queues that are accessible to all connections. Sending messages is particularly tricky since we must monitor the queue for available messages and the sending link for available credit in order to send messages.
electron/broker takes advantage of the
electron package, which hides all the event handling and passing of messages between goroutines beind behind straightforward interfaces for sending and receiving messages. The electron broker can implement links as simple goroutines that loop popping messages from a queue and sending them or receiving messages and pushing them to a queue.