Spring Web Reactive not working as war file deployed on Tomcat 8.5

Question

I have Spring Boot (2.0.0 M5) application which provides some REST API. I'd like to implement this API using RouterFunctions.

While I'm running app using embedded Jetty everything works fine.

When I convert the app to WAR file (following documentation here) and deploy it to Tomcat 8.5 I always get 404 when trying to call any of the endpoints.

I can see in the log that endpoints are recognised:

[ost-startStop-1] s.w.r.r.m.a.RequestMappingHandlerMapping : Mapped "{[/say-hello],methods=[GET]}" onto java.lang.String com.example.demo.DemoController.test()
[ost-startStop-1] o.s.w.r.f.s.s.RouterFunctionMapping: Mapped /api => {
    /v1 => {
       /status -> 
          com.example.demo.DemoApplication$$Lambda$189/1904651750@5fdc83e
   }
}

But when calling curl -v http://localhost:8080/demo/say-hello or curl -v http://localhost:8080/demo/api/v1/status I see default Tomcat 404 page. The path is correct, I rename .war to demo.war before deploying it.

Did anybody come across similar issue? You can find the code here.

Answer 1

I'm afraid the WAR deployment model is not supported in Spring Boot for WebFlux at the moment. Spring Framework does support that model (although I'm not sure it supports deploying an app to a non-root context).

You can always create an issue on the Spring Boot issue tracker, but I'm not sure this will be implemented, as deploying to a Servlet container is not the primary focus there (and you can't do that with Netty).

Quick note: adding @EnableWebFlux is a signal that you'd like to take the WebFlux configuration in your own hands and that Spring Boot should not auto-configure things for you in that space.