dependency cycle on spring WebSocket interceptor and spring cloud stream

i am trying to create a websocket interceptor that do send a message using MessageChannel from spring cloud stream . i am facing a dependency cycle

┌─────┐
|  myChannelInterceptor defined in file [/Users/shahbour/IdeaProjects/proxy/target/classes/com/xxxxx/proxy/broker/MyChannelInterceptor.class]
↑     ↓
|  com.xxxx.proxy.service.XxxxxBinding (field private java.util.Map org.springframework.cloud.stream.binding.BindableProxyFactory.bindingTargetFactories)
↑     ↓
|  org.springframework.cloud.stream.config.BindingServiceConfiguration (field private java.util.List org.springframework.cloud.stream.config.BindingServiceConfiguration.customMessageConverters)
↑     ↓
|  org.springframework.web.socket.config.annotation.DelegatingWebSocketMessageBrokerConfiguration
↑     ↓
|  webSocketConfig defined in file [/Users/shahbour/IdeaProjects/proxy/target/classes/com/xxxx/proxy/config/WebSocketConfig.class]
└─────┘

My problem is that i need to inject a MessageChannel into the websocket interceptor

I am receiving the below error if i use @Autowire

org.springframework.context.ApplicationContextException: Failed to start bean 'subProtocolWebSocketHandler'; nested exception is java.lang.IllegalArgumentException: No handlers
    at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:167) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:50) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:348) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:151) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:114) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:879) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.finishRefresh(EmbeddedWebApplicationContext.java:144) ~[spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:545) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:737) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:370) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:314) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1162) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1151) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at com.xxxx.proxy.xxxxxxProxyApplication.main(XxxxxProxyApplication.java:29) [classes/:na]
Caused by: java.lang.IllegalArgumentException: No handlers
    at org.springframework.util.Assert.isTrue(Assert.java:92) ~[spring-core-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.socket.messaging.SubProtocolWebSocketHandler.start(SubProtocolWebSocketHandler.java:244) ~[spring-websocket-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:175) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    ... 15 common frames omitted

Solution

OK. Thank you! No I see the problem.

Look:

Your MyChannelInterceptor depends on the auto-created channel by the BinderService.
That one tries to infer MessageConverters from the application context.
The AbstractMessageBrokerConfiguration provides one in face of CompositeMessageConverter brokerMessageConverter
That class is instantiated by the @EnableWebSocketMessageBroker
which, in turn, scans your WebSocketConfig because of the AbstractWebSocketMessageBrokerConfigurer
And this last one wants your MyChannelInterceptor to be injected.

Not sure how to fix that as an out-of-the-box feature, but here is some kind of workaround:

public class MyChannelInterceptor extends ChannelInterceptorAdapter {

    @Autowired
    private MessageChannel output;

@Configuration
public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer {

    @Bean
    public MyChannelInterceptor myChannelInterceptor() {
        return new MyChannelInterceptor();
    }
...
@Override
public void configureClientInboundChannel(ChannelRegistration registration) {
    registration.setInterceptors(myChannelInterceptor());
}