Migration Guide from grpc-ecosystem

[fisco-unimatic]

Is there a migration guide? I guess there are a lot of us migrating now that Spring Boot 4 is out. A guide would be really useful.
Also, do you recommend migrating to pre-version-1 first, while still on Spring Boot 3, and then doing the Grpc and Boot upgrades at the same time. Or just go striaght to the latest Grpc version and Spring Boot 4 in one big migration. I don't know whether it's worth going to v0.12.0 first, or is that so different to 1.x.x that it's not worth it?

[dsyer]

A migration guide is an excellent idea. Hopefully people will share their experiences here and we can pick up some pointers.

0.12.0 is not very different to 1.0.2. I would be interested to hear if it helps the transition - it might soften the blow to not have to upgrade Spring Boot at the same time.

[fisco-unimatic]

I ended up doing both upgrades in one go. It would probably have made more sense to do them one at a time.
Here are some brief notes. Hopefully, they'll be of use to someone.

• Replace net.devh:grpc-client-spring-boot-starter with org.springframework.grpc:spring-grpc-spring-boot-starter in your gradle or pom file.
  And org.springframework.grpc:spring-grpc-test, too.

• Classes annotated @GrpcGlobalServerInterceptor should now be annotated @Component and @GlobalServerInterceptor instead. (Search and replace imports and annotation.)
  Classes annotated @GrpcGlobalClientInterceptor should now be annotated @Component and @GlobalClientInterceptor instead. (Search and replace imports and annotation.)
  Search and replace net.devh.boot.grpc.server.service.GrpcService with org.springframework.grpc.server.service.GrpcService.

• Classes annotated @GrpcAdvice with methods annotated @GrpcExceptionHandler should now be annotated @Component instead and implement GrpcExceptionHandler.

• Search and replace net.devh.boot.grpc.server.security.interceptors.AuthenticatingServerInterceptor.SECURITY_CONTEXT_KEY
  with org.springframework.grpc.server.security.GrpcSecurity.SECURITY_CONTEXT_KEY

• You may need to implement a AuthenticationProcessInterceptor and annotate it with @GlobalServerInterceptor. See Declarative Security with Spring Security.

• If you implement GrpcAuthenticationReader, you'll need to implement GrpcAuthenticationExtractor instead.

• Annotate integration tests with @AutoConfigureInProcessTransport if they use an in-process server,
  and autowire your stubs instead of using the @GrpcClient("inProcess") annotation and grpc.server.inProcessName and grpc.client.inProcess.address properties.
  If you don't already declare these stubs in a configuration, you may need to do so in a test configuration, and create them with an autowired GrpcChannelFactory.
  You may also need to @ImportAutoConfiguration({InProcessTestAutoConfiguration.class, GrpcServerAutoConfiguration.class}).

• In your application properties, replace grpc.server.port with spring.grpc.server.port.