Get running

$ docker-compose up -d

Creating network "tyk-rmq-middleware_default" with the default driver
Creating tyk-rmq-middleware_rmq_1 ... done
Creating tyk-rmq-middleware_worker_1          ... done
Creating tyk-rmq-middleware_middleware-grpc_1 ... done

This will start a RMQ server listening on port 5672 for messages, and 15672 admin interface. To access the admin interface, visit http://localhost:15672 and login with highly secure credentials guest:guest.

The worker is a golang app - which simply listens on the rpc_queue queue, and replies to messages on the reply_to queue with correlation_id from the incoming request.

Import API definition

Import ./apidefinitions/sentence_generator.json into Tyk Dashboard as a new API.

See it working

$ curl -X POST  http://localhost:8080/httpbin/post -d '{"firstName": "Ahmet"}'
{
    "error": "lastName: lastName is required; age: age is required"
}

Ok, so when we fix the request - meeting validation rules:

$ curl -X POST  http://localhost:8080/httpbin/post -d '{"firstName": "Ahmet", "lastName": "Soormally", "age": 36}'

{"sentence":"Ahmet Soormally is 36 year's old"}

What just happened?

1. Tyk validated the incoming request with JSON Schema validate JSON plugin.
2. Tyk called gRPC middleware POST hook MyRabbitHook
3. MyRabbitHook created a temporary reply_to queue, with a random correlation_id Then sent a message to rpc_queue for a worker to pick up.
4. worker process was listening to rpc_queue for messages, and when it received the message, generated the sentence based on body contents.
5. Once it generated the response body, it placed the message onto the temporary reply_to queue with appropriate correlation_id.

Note

This is a PoC. I would highly recommend that middleware-grpc didn't establish a connection & disconnect from rabbit for every RPC call.