=== Stub Runner Spring AMQP
Spring Cloud Contract Verifier Stub Runner's messaging module provides an easy way to integrate with Spring AMQP's Rabbit Template.
For the provided artifacts it will automatically download the stubs and register the required
routes.
The integration tries to work standalone, that is without interaction with a running RabbitMQ message broker.
It expects a `RabbitTemplate` on the application context and uses it as a spring boot test `@SpyBean`.
Thus it can use the mockito spy functionality to verify and introspect messages sent by the application.
On the message consumer side, it considers all `@RabbitListener` annotated endpoints as well as all `SimpleMessageListenerContainer`s on the application context.
As messages are usually sent to exchanges in AMQP the message contract contains the exchange name as the destination.
Message listeners on the other side are bound to queues. Bindings connect an exchange to a queue.
If message contracts are triggered the Spring AMQP stub runner integration will look for bindings on the application context that match this exchange.
Then it collects the queues from the Spring exchanges and tries to find messages listeners bound to these queues.
The message is triggered to all matching message listeners.
==== Adding it to the project
It's enough to have both Spring AMQP and Spring Cloud Contract Stub Runner on the classpath and set the property `stubrunner.amqp.enabled=true`.
Remember to annotate your test class with `@AutoConfigureMessageVerifier`.
==== Examples
===== Stubs structure
Let us assume that we have the following Maven repository with a deployed stubs for the
`spring-cloud-contract-amqp-test` application.
[source,bash,indent=0]
----
└── .m2
└── repository
└── com
└── example
└── spring-cloud-contract-amqp-test
├── 0.4.0-SNAPSHOT
│ ├── spring-cloud-contract-amqp-test-0.4.0-SNAPSHOT.pom
│ ├── spring-cloud-contract-amqp-test-0.4.0-SNAPSHOT-stubs.jar
│ └── maven-metadata-local.xml
└── maven-metadata-local.xml
----
And the stubs contain the following structure:
[source,bash,indent=0]
----
├── META-INF
│ └── MANIFEST.MF
└── contracts
└── shouldProduceValidPersonData.groovy
----
Let's consider the following contract:
[source,groovy]
----
include::src/test/groovy/org/springframework/cloud/contract/stubrunner/messaging/amqp/AmqpStubRunnerSpec.groovy[tags=amqp_contract,indent=0]
----
and the following Spring configuration:
[source,yaml]
----
include::src/test/resources/application.yml[]
----
===== Triggering the message
So to trigger a message using the contract above we'll use the `StubTrigger` interface as follows.
[source,groovy]
----
include::src/test/groovy/org/springframework/cloud/contract/stubrunner/messaging/amqp/AmqpStubRunnerSpec.groovy[tags=client_trigger,indent=0]
----
The message has the destination `contract-test.exchange` so the Spring AMQP stub runner integration looks for bindings related to this exchange.
[source,java]
----
include::src/main/java/org/springframework/cloud/contract/stubrunner/messaging/amqp/AmqpMessagingApplication.java[tags=amqp_binding,indent=0]
----
The binding definition binds the queue `test.queue`.
So the following listener definition is a match and is invoked with the contract message.
[source,java]
----
include::src/main/java/org/springframework/cloud/contract/stubrunner/messaging/amqp/AmqpMessagingApplication.java[tags=amqp_listener,indent=0]
----
Also, the following annotated listener represents a match and would be invoked.
[source,java]
----
include::src/main/java/org/springframework/cloud/contract/stubrunner/messaging/amqp/MessageSubscriberRabbitListener.java[tags=amqp_annotated_listener,indent=0]
----
NOTE: The message is directly handed over to the `onMessage` method of the `MessageListener` associated with the matching `SimpleMessageListenerContainer`.
===== Spring AMQP Test Configuration
In order to avoid that Spring AMQP is trying to connect to a running broker during our tests we configure a mock `ConnectionFactory`.
To disable the mocked ConnectionFactory set the property `stubrunner.amqp.mockConnection=false`
[source,yaml]
----
stubrunner:
amqp:
mockConnection: false
----
