Spring-webflux application startup failures

Question

The application is failing during the startup with this error:

The bean 'requestDataValueProcessor', defined in class path resource [org/springframework/security/config/annotation/web/configuration/WebMvcSecurityConfiguration.class], could not be registered. A bean with that name has already been defined in class path resource [org/springframework/security/config/annotation/web/reactive/WebFluxSecurityConfiguration.class] and overriding is disabled.

All team members have the same problem and it seems that even if we're checking out an old git tag, the same problem persist. We've checked all the build files and dependencies, and nothing seemed to be changed in the last period of time. What's even more interesting is that the Bamboo seemed to run the build and the IT's pack with success with a day before, but today's morning it seem that the same issue is replicated there.

Not sure exactly why is complaining about WebMvcSecurityConfiguration , since we're using only reactive security in our project. So at this point we don't have any spring-mvc dependencies..

Does anyone have any clue? Thx

Answer 1

So after we've enabled debug level logs on spring and force spring app to use only the reactive configurations like this:

 spring:
  main:
   web-application-type: reactive

it seemed that the springfox dependencies were failing with:

 java.lang.NoSuchMethodError: org.springframework.util.MultiValueMap.addIfAbsent(Ljava/lang/Object;Ljava/lang/Object;)V
at springfox.documentation.spring.web.scanners.ModelSpecificationRegistryBuilder.lambda$add$0(ModelSpecificationRegistryBuilder.java:37)
at java.base/java.util.Optional.ifPresent(Optional.java:183)
at springfox.documentation.spring.web.scanners.ModelSpecificationRegistryBuilder.add(ModelSpecificationRegistryBuilder.java:34)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
at

So that error ^^^ point us towards sprinfox dependencies which were:

compile ("io.springfox:springfox-swagger-ui:3.0.0-SNAPSHOT")
compile ("io.springfox:springfox-swagger2:3.0.0-SNAPSHOT")
compile ("io.springfox:springfox-spring-webflux:3.0.0-SNAPSHOT")

After furthermore investigation, it seemed that some of those contains the spring-mvc dependency and that interfere with the spring-webflux one, and the application got confused which beans to inject.

We've downgrade those dependencies to 2.10.0 , and everything seems to work now. My guess is that they've made some releases with that snapshot version and that include spring mvc, but until now it was absent. Lesson learned, never use some external libraries snapshots versions, otherwise you could end up in a very bad situation.

Answer 2

XXX-SNAPSHOT Dependencies are not the stable ones. we were using <springfox.version>3.0.0-SNAPSHOT</springfox.version> which suddenly stopped working. So below solution worked for us.

<springfox.version>2.10.5</springfox.version>

Cheers!!