Add sample and integration test

samples/grpc-server/src/main/java/org/springframework/grpc/sample/GrpcServerApplication.java

@@ -2,6 +2,12 @@ package org.springframework.grpc.sample;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+import org.springframework.grpc.server.GlobalServerInterceptor;
+import org.springframework.grpc.server.exception.GrpcExceptionHandlerInterceptor;
+
+import io.grpc.ServerInterceptor;
+import io.grpc.Status;
 
 @SpringBootApplication
 public class GrpcServerApplication {
@@ -10,4 +16,15 @@ public class GrpcServerApplication {
 		SpringApplication.run(GrpcServerApplication.class, args);
 	}
 
+	@GlobalServerInterceptor
+	@Bean
+	public ServerInterceptor globalInterceptor() {
+		return new GrpcExceptionHandlerInterceptor(exception -> {
+			if (exception instanceof IllegalArgumentException) {
+				return Status.INVALID_ARGUMENT.withDescription(exception.getMessage());
+			}
+			return null;
+		});
+	}
+
 }

samples/grpc-server/src/main/java/org/springframework/grpc/sample/GrpcServerService.java

@@ -18,6 +18,12 @@ public class GrpcServerService extends SimpleGrpc.SimpleImplBase {
 	@Override
 	public void sayHello(HelloRequest req, StreamObserver<HelloReply> responseObserver) {
 		log.info("Hello " + req.getName());
+		if (req.getName().startsWith("error")) {
+			throw new IllegalArgumentException("Bad name: " + req.getName());
+		}
+		if (req.getName().startsWith("internal")) {
+			throw new RuntimeException();
+		}
 		HelloReply reply = HelloReply.newBuilder().setMessage("Hello ==> " + req.getName()).build();
 		responseObserver.onNext(reply);
 		responseObserver.onCompleted();

samples/grpc-server/src/test/java/org/springframework/grpc/sample/GrpcServerIntegrationTests.java

@@ -17,6 +17,7 @@
 package org.springframework.grpc.sample;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.Assert.assertThrows;
 
 import org.junit.jupiter.api.Nested;
 import org.junit.jupiter.api.Test;
@@ -35,6 +36,8 @@ import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.context.ActiveProfiles;
 
 import io.grpc.ManagedChannel;
+import io.grpc.StatusRuntimeException;
+import io.grpc.Status.Code;
 
 /**
  * More detailed integration tests for {@link GrpcServerFactory gRPC server factories} and
@@ -53,6 +56,32 @@ class GrpcServerIntegrationTests {
 
 	}
 
+	@Nested
+	@SpringBootTest
+	class ServerWithException {
+
+		@Test
+		void specificErrorResponse(@Autowired GrpcChannelFactory channels) {
+			SimpleGrpc.SimpleBlockingStub client = SimpleGrpc
+				.newBlockingStub(channels.createChannel("0.0.0.0:0").build());
+			assertThat(assertThrows(StatusRuntimeException.class,
+					() -> client.sayHello(HelloRequest.newBuilder().setName("error").build()))
+				.getStatus()
+				.getCode()).isEqualTo(Code.INVALID_ARGUMENT);
+		}
+
+		@Test
+		void defaultErrorResponseIsUnknown(@Autowired GrpcChannelFactory channels) {
+			SimpleGrpc.SimpleBlockingStub client = SimpleGrpc
+				.newBlockingStub(channels.createChannel("0.0.0.0:0").build());
+			assertThat(assertThrows(StatusRuntimeException.class,
+					() -> client.sayHello(HelloRequest.newBuilder().setName("internal").build()))
+				.getStatus()
+				.getCode()).isEqualTo(Code.UNKNOWN);
+		}
+
+	}
+
 	@Nested
 	@SpringBootTest(properties = { "spring.grpc.server.host=0.0.0.0", "spring.grpc.server.port=0",
 			"spring.grpc.inprocess.enabled=false" })