GrpcExceptionHandler does not seem to be called when using Reactor generated stubs

[svametcalf]

Greetings!

First of all, very glad to see that gRPC is becoming supported by the Spring ecosystem.

I spent the day attempting to migrate to use this library and found that the GrpcExceptiionHandler was not working as I would have expected it to.

I have created a fork of this project and modified the grpc-reactor sample to demonstrate exactly what is going on here: https://github.com/svametcalf/spring-grpc/tree/reactor-error-handler. In short, I have registered the following exception handler:

@Bean
    GrpcExceptionHandler grpcExceptionHandler() {
        log.info("GrpcExceptionHandler");
        return ex -> {
            if(ex instanceof IllegalArgumentException ){
                log.error("Error in grpc exception", ex);
                return Status.INVALID_ARGUMENT.withDescription(ex.getMessage());
            }
            return Status.INTERNAL.withCause(ex).withDescription(ex.getMessage());
        };
    }

I am getting the following responses when using grpcurl:

❯ grpcurl -d '{"name":"error"}' -plaintext localhost:9090 Simple.SayHello
ERROR:
  Code: Unknown
  Message: 

and

❯ grpcurl -d '{"name":"internal"}' -plaintext localhost:9090 Simple.SayHello
ERROR:
  Code: Unknown
  Message: 

Shouldn't those error codes be INVALID and INTERNAL respectively?

[dsyer]

That's sort of interesting. The Salesforce-generated code swallows the exception (and closes the server call), instead of rethrowing. I don't see any options to change that. Maybe you should take it up with the reactive-grpc authors? You can follow an (old) thread here: salesforce/reactive-grpc#234. That issue is still open, and they merged a PR that added the onErrorMap() method to the base BindableService implementation, so you can work around the problem by handling the errors locally in your service. Doesn't seem like a great solution to me.

[dsyer]

This should be working now (and I added a test), but not in AOT (until spring-projects/spring-framework#34642 is fixed).

[svametcalf]

Thanks for the quick turnaround!

[svametcalf]

Is this what you mean when you mean that the AOT needs to be fixed?

Exception in thread "main" org.springframework.test.context.aot.TestContextAotException: Failed to generate AOT artifacts for test classes [org.springframework.grpc.sample.GrpcServerApplicationTests]
	at org.springframework.test.context.aot.TestContextAotGenerator.lambda$processAheadOfTime$5(TestContextAotGenerator.java:286)
	at java.base/java.util.LinkedHashMap.forEach(LinkedHashMap.java:721)
	at org.springframework.util.MultiValueMapAdapter.forEach(MultiValueMapAdapter.java:179)
	at org.springframework.test.context.aot.TestContextAotGenerator.processAheadOfTime(TestContextAotGenerator.java:244)
	at org.springframework.test.context.aot.TestContextAotGenerator.processAheadOfTime(TestContextAotGenerator.java:205)
	at org.springframework.test.context.aot.TestAotProcessor.performAotProcessing(TestAotProcessor.java:91)
	at org.springframework.test.context.aot.TestAotProcessor.doProcess(TestAotProcessor.java:72)
	at org.springframework.test.context.aot.TestAotProcessor.doProcess(TestAotProcessor.java:39)
	at org.springframework.context.aot.AbstractAotProcessor.process(AbstractAotProcessor.java:82)
	at org.springframework.boot.test.context.SpringBootTestAotProcessor.main(SpringBootTestAotProcessor.java:63)
Caused by: org.springframework.test.context.aot.TestContextAotException: Failed to process test class [org.springframework.grpc.sample.GrpcServerApplicationTests] for AOT
	at org.springframework.test.context.aot.TestContextAotGenerator.processAheadOfTime(TestContextAotGenerator.java:323)
Caused by: org.springframework.test.context.aot.TestContextAotException: Failed to process test class [org.springframework.grpc.sample.GrpcServerApplicationTests] for AOT

	at org.springframework.test.context.aot.TestContextAotGenerator.lambda$processAheadOfTime$5(TestContextAotGenerator.java:277)
	... 9 more
Caused by: org.springframework.beans.factory.aot.AotBeanProcessingException: Error processing bean with name 'org.springframework.grpc.autoconfigure.client.ClientScanConfiguration.default': instance supplier is not supported
Caused by: org.springframework.beans.factory.aot.AotBeanProcessingException: Error processing bean with name 'org.springframework.grpc.autoconfigure.client.ClientScanConfiguration.default': instance supplier is not supported

	at org.springframework.beans.factory.aot.DefaultBeanRegistrationCodeFragments.getTarget(DefaultBeanRegistrationCodeFragments.java:81)
	at org.springframework.beans.factory.aot.BeanDefinitionMethodGenerator.generateBeanDefinitionMethod(BeanDefinitionMethodGenerator.java:85)
	at org.springframework.beans.factory.aot.BeanRegistrationsAotContribution$BeanDefinitionsRegistrationGenerator.generateBeanRegistration(BeanRegistrationsAotContribution.java:226)
	at org.springframework.beans.factory.aot.BeanRegistrationsAotContribution$BeanDefinitionsRegistrationGenerator.lambda$generateRegisterBeanDefinitionMethods$2(BeanRegistrationsAotContribution.java:209)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at org.springframework.beans.factory.aot.BeanRegistrationsAotContribution$BeanDefinitionsRegistrationGenerator.generateRegisterBeanDefinitionMethods(BeanRegistrationsAotContribution.java:207)
	at org.springframework.beans.factory.aot.BeanRegistrationsAotContribution$BeanDefinitionsRegistrationGenerator.lambda$generateRegisterBeanDefinitionsMethod$0(BeanRegistrationsAotContribution.java:171)
	at org.springframework.aot.generate.GeneratedMethod.<init>(GeneratedMethod.java:54)
	at org.springframework.aot.generate.GeneratedMethods.add(GeneratedMethods.java:112)
	at org.springframework.aot.generate.GeneratedMethods.add(GeneratedMethods.java:89)
	at org.springframework.beans.factory.aot.BeanRegistrationsAotContribution$BeanDefinitionsRegistrationGenerator.generateRegisterBeanDefinitionsMethod(BeanRegistrationsAotContribution.java:166)
	at org.springframework.beans.factory.aot.BeanRegistrationsAotContribution.applyTo(BeanRegistrationsAotContribution.java:77)
	at org.springframework.context.aot.BeanFactoryInitializationAotContributions.applyTo(BeanFactoryInitializationAotContributions.java:96)
	at org.springframework.context.aot.ApplicationContextAotGenerator.lambda$processAheadOfTime$0(ApplicationContextAotGenerator.java:58)
	at org.springframework.context.aot.ApplicationContextAotGenerator.withCglibClassHandler(ApplicationContextAotGenerator.java:67)
	at org.springframework.context.aot.ApplicationContextAotGenerator.processAheadOfTime(ApplicationContextAotGenerator.java:53)
	at org.springframework.test.context.aot.TestContextAotGenerator.processAheadOfTime(TestContextAotGenerator.java:319)
	... 10 more

Execution failed for task ':grpc-reactive:processTestAot'.
> Process 'command '/home/schuyler/.gradle/jdks/eclipse_adoptium-17-amd64-linux.2/bin/java'' finished with non-zero exit value 1

I am trying to run the tests on my fork using Gradle

[dsyer]

No, that's unrelated. Gradle is configured to compile AOT tests by default. Don't ask me why. Ask the Spring Boot team (I think it's a "feature" of the Boot Gradle plugin). Mind you, it shouldn't fail that way on that sample, so can you open a new issue here please?

[svametcalf]

I am getting a new error after pulling main, and have logged the error here: #147