RabbitMQ is a great infrastructure software, but there is a not very well known feature that allow us to create WebSockets applications its great STOMP integration. In this talk I’ll show how we can very easily create a very robust WebSocket application using RabbitMQ, Spring Integration and, of course, Groovy.

1. DOWN THE
HOLE
@alotor

2. Alonso Torres
@alotor

4. Spring Integration
WEB SOCKETS

5. Browser
/GET
200 OK

6. SEND X
BTW, Your thing
SEND Y
Browser

7. SUBSCRIBE X
X1
X2
X3
Browser

8. Web Sockets
Web standard for bi-directional communication
between the browser and a Web Server
● Non-blocking asynchronous communication
● Push notifications

9. OK,
maybe you already knew this

10. Asynchronous communication?
Pub/sub?
But...

11. ● Robust
● Reliable
● Scalable
● Interoperable (as in microservices?)
● Just fast
● Easy to develop (spoiler alert!)
IT’S AWESOME!!

12. Logic
Logic
WebSockets
????

13. How do I transform
RabbitMQ
in a WebSocket server

14. rabbitmq-plugins enable rabbitmq_stomp

16. STOMP
● Simple Text Protocol
● Give semantics to the WebSockets
● For example:
○ CONNECT
○ SEND
○ SUBSCRIBE

17. STOMP
Logic
Logic
WebSockets

19. https://github.com/alotor/greach2016-rabbitmq

22. STOMP
WebSockets AMQP
Twitter Streaming
API

24. STOMP
WebSockets AMQP
Twitter Streaming
API

25. @Service
class MainService {
@Autowired
WorkerGateway workerGateway
public void startTopic(Map message) {
new TwitterWorker(auth, message.topic).fetchTweets {
String topic, String json ->
def tweet = jsonSerializer.fromJson(json.bytes)
workerGateway.broadcastMessage(topic, tweet)
}
}
}

26. STOMP
WebSockets AMQP
Twitter Streaming
API

27. STOMP
WebSockets AMQP
Twitter Streaming
API

28. @Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig
extends AbstractWebSocketMessageBrokerConfigurer {
@Override
public void configureMessageBroker(MessageBrokerRegistry config) {
def brokerRelay =
config.enableStompBrokerRelay("/queue", "/topic")
// Configure the relay data
}

29. @Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry
.addEndpoint("/stomp")
.setAllowedOrigins("*") // CORS configuration
}

30. STOMP
WebSockets AMQP
Twitter Streaming
API

31. service-activator
jsonSerializer.fromJson transformer
request
inbound-adapter
mainService.startTopic
Spring Integration

32. @Bean
public IntegrationFlow amqpInboundGateway(
ConnectionFactory connectionFactory,
JsonSerializer jsonSerializer,
MainService mainService) {
IntegrationFlows
.from(Amqp.inboundAdapter(connectionFactory, "request"))
.transform(jsonSerializer, "fromJson")
.handle(mainService, "startTopic")
.get();
}

33. gateway
jsonSerializer.toJson transformer
topic
outbound-adapter
workerGateway.broadcastMessage
Spring Integration

34. @MessagingGateway(defaultRequestChannel = "responseChannel")
interface WorkerGateway {
void broadcastMessage(
@Header("routingKey") String topic, @Payload Map message)
}

35. @Service
class MainService {
@Autowired
WorkerGateway workerGateway
public void startTopic(Map message) {
new TwitterWorker(auth, message.topic).fetchTweets {
String topic, String json ->
def tweet = jsonSerializer.fromJson(json.bytes)
workerGateway.broadcastMessage(topic, tweet)
}
}
}

36. @Bean
public IntegrationFlow amqpOutboundGateway(
AmqpTemplate amqpTemplate,
JsonSerializer jsonSerializer) {
IntegrationFlows
.from("responseChannel")
.transform(jsonSerializer, "toJson")
.handle(Amqp.outboundAdapter(amqpTemplate)
.exchangeName("amq.topic")
.routingKeyExpression("headers.routingKey"))
.get()
}

40. ● Security (JWT, tokens…)
● Infrastructure hell (docker!)
The bad news

42. https://github.com/alotor/greach2016-rabbitmq
@alotor
Questions?