Add explicit support for running on separate port

If the user wants a second port for gRPC that should be possible
(and was the only way with the old ecosystem projects). This change
adds a webflux sample and support for
spring.grpc.server.{servlet,reactive}.enabled to be explicitly
"false" to disable the embedded services.

N.B. embedded services are not yet supported in webflux so the flag
has no effect, except to disable gRPC completely if it is "true".

Author: Dave Syer

samples/grpc-tomcat/src/test/java/org/springframework/grpc/sample/ListenOnTwoPortsTests.java

@@ -0,0 +1,59 @@
+package org.springframework.grpc.sample;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.TestConfiguration;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Lazy;
+import org.springframework.grpc.client.GrpcChannelFactory;
+import org.springframework.grpc.sample.proto.HelloReply;
+import org.springframework.grpc.sample.proto.HelloRequest;
+import org.springframework.grpc.sample.proto.SimpleGrpc;
+import org.springframework.grpc.test.LocalGrpcPort;
+import org.springframework.test.annotation.DirtiesContext;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT,
+		properties = { "spring.grpc.server.servlet.enabled=false", "spring.grpc.server.port=0" })
+public class ListenOnTwoPortsTests {
+
+	private static Log log = LogFactory.getLog(ListenOnTwoPortsTests.class);
+
+	public static void main(String[] args) {
+		new SpringApplicationBuilder(GrpcServerApplication.class, ExtraConfiguration.class)
+			.run("--spring.grpc.server.servlet.enabled=false", "--spring.grpc.server.port=9091");
+	}
+
+	@Autowired
+	private SimpleGrpc.SimpleBlockingStub stub;
+
+	@Test
+	@DirtiesContext
+	void contextLoads() {
+	}
+
+	@Test
+	@DirtiesContext
+	void serverResponds() {
+		log.info("Testing");
+		HelloReply response = stub.sayHello(HelloRequest.newBuilder().setName("Alien").build());
+		assertEquals("Hello ==> Alien", response.getMessage());
+	}
+
+	@TestConfiguration
+	static class ExtraConfiguration {
+
+		@Bean
+		@Lazy
+		SimpleGrpc.SimpleBlockingStub stub(GrpcChannelFactory channels, @LocalGrpcPort int port) {
+			return SimpleGrpc.newBlockingStub(channels.createChannel("0.0.0.0:" + port).build());
+		}
+
+	}
+
+}

samples/grpc-webflux/README.md

@@ -0,0 +1,61 @@
+# Spring Boot gRPC Sample
+
+This project is a copy one of the samples from the [gRPC Spring Boot Starter](https://github.com/yidongnan/grpc-spring-boot-starter/blob/master/examples/local-grpc-server/build.gradle). Build and run any way you like to run Spring Boot. E.g:
+
+```
+$ ./mvnw spring-boot:run
+...
+  .   ____          _            __ _ _
+ /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
+( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
+ \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
+  '  |____| .__|_| |_|_| |_\__, | / / / /
+ =========|_|==============|___/=/_/_/_/
+ :: Spring Boot ::                (v3.0.0)
+
+2022-12-08T05:32:24.934-08:00  INFO 551632 --- [           main] com.example.demo.DemoApplication         : Starting DemoApplication using Java 17.0.5 with PID 551632 (/home/dsyer/dev/scratch/demo/target/classes started by dsyer in /home/dsyer/dev/scratch/demo)
+2022-12-08T05:32:24.938-08:00  INFO 551632 --- [           main] com.example.demo.DemoApplication         : No active profile set, falling back to 1 default profile: "default"
+2022-12-08T05:32:25.377-08:00  WARN 551632 --- [           main] ocalVariableTableParameterNameDiscoverer : Using deprecated '-debug' fallback for parameter name resolution. Compile the affected code with '-parameters' instead or avoid its introspection: net.devh.boot.grpc.server.autoconfigure.GrpcHealthServiceAutoConfiguration
+2022-12-08T05:32:25.416-08:00  WARN 551632 --- [           main] ocalVariableTableParameterNameDiscoverer : Using deprecated '-debug' fallback for parameter name resolution. Compile the affected code with '-parameters' instead or avoid its introspection: net.devh.boot.grpc.server.autoconfigure.GrpcServerAutoConfiguration
+2022-12-08T05:32:25.425-08:00  WARN 551632 --- [           main] ocalVariableTableParameterNameDiscoverer : Using deprecated '-debug' fallback for parameter name resolution. Compile the affected code with '-parameters' instead or avoid its introspection: net.devh.boot.grpc.server.autoconfigure.GrpcServerFactoryAutoConfiguration
+2022-12-08T05:32:25.427-08:00  INFO 551632 --- [           main] g.s.a.GrpcServerFactoryAutoConfiguration : Detected grpc-netty: Creating NettyGrpcServerFactory
+2022-12-08T05:32:25.712-08:00  INFO 551632 --- [           main] n.d.b.g.s.s.AbstractGrpcServerFactory    : Registered gRPC service: Simple, bean: grpcServerService, class: com.example.demo.GrpcServerService
+2022-12-08T05:32:25.712-08:00  INFO 551632 --- [           main] n.d.b.g.s.s.AbstractGrpcServerFactory    : Registered gRPC service: grpc.health.v1.Health, bean: grpcHealthService, class: io.grpc.protobuf.services.HealthServiceImpl
+2022-12-08T05:32:25.712-08:00  INFO 551632 --- [           main] n.d.b.g.s.s.AbstractGrpcServerFactory    : Registered gRPC service: grpc.reflection.v1alpha.ServerReflection, bean: protoReflectionService, class: io.grpc.protobuf.services.ProtoReflectionService
+2022-12-08T05:32:25.820-08:00  INFO 551632 --- [           main] n.d.b.g.s.s.GrpcServerLifecycle          : gRPC Server started, listening on address: *, port: 9090
+2022-12-08T05:32:25.831-08:00  INFO 551632 --- [           main] com.example.demo.DemoApplication         : Started DemoApplication in 1.264 seconds (process running for 1.623)
+```
+
+The server starts by default on port 9090. Test with [gRPCurl](https://github.com/fullstorydev/grpcurl):
+
+```
+$ grpcurl -d '{"name":"Hi"}' -plaintext localhost:9090 Simple.SayHello
+{
+  "message": "Hello ==\u003e Hi"
+}
+```
+
+## Native Image
+
+The app compiles to a native image if the JVM is GraalVM:
+
+```
+$ ./mvnw -Pnative native:compile
+$ ./target/demo
+  .   ____          _            __ _ _
+ /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
+( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
+ \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
+  '  |____| .__|_| |_|_| |_\__, | / / / /
+ =========|_|==============|___/=/_/_/_/
+ :: Spring Boot ::                (v3.0.0)
+
+2022-12-08T05:36:54.365-08:00  INFO 554359 --- [           main] com.example.demo.DemoApplication         : Starting AOT-processed DemoApplication using Java 17.0.5 with PID 554359 (/home/dsyer/dev/scratch/demo/target/demo started by dsyer in /home/dsyer/dev/scratch/demo)
+2022-12-08T05:36:54.366-08:00  INFO 554359 --- [           main] com.example.demo.DemoApplication         : No active profile set, falling back to 1 default profile: "default"
+2022-12-08T05:36:54.377-08:00  INFO 554359 --- [           main] g.s.a.GrpcServerFactoryAutoConfiguration : Detected grpc-netty: Creating NettyGrpcServerFactory
+2022-12-08T05:36:54.392-08:00  INFO 554359 --- [           main] n.d.b.g.s.s.AbstractGrpcServerFactory    : Registered gRPC service: Simple, bean: grpcServerService, class: com.example.demo.GrpcServerService
+2022-12-08T05:36:54.392-08:00  INFO 554359 --- [           main] n.d.b.g.s.s.AbstractGrpcServerFactory    : Registered gRPC service: grpc.health.v1.Health, bean: grpcHealthService, class: io.grpc.protobuf.services.HealthServiceImpl
+2022-12-08T05:36:54.392-08:00  INFO 554359 --- [           main] n.d.b.g.s.s.AbstractGrpcServerFactory    : Registered gRPC service: grpc.reflection.v1alpha.ServerReflection, bean: protoReflectionService, class: io.grpc.protobuf.services.ProtoReflectionService
+2022-12-08T05:36:54.396-08:00  INFO 554359 --- [           main] n.d.b.g.s.s.GrpcServerLifecycle          : gRPC Server started, listening on address: *, port: 9090
+2022-12-08T05:36:54.396-08:00  INFO 554359 --- [           main] com.example.demo.DemoApplication         : Started DemoApplication in 0.046 seconds (process running for 0.052)
+```

samples/grpc-webflux/build.gradle

@@ -0,0 +1,61 @@
+plugins {
+    id 'java'
+    id 'org.springframework.boot' version '3.4.0'
+    id 'io.spring.dependency-management' version '1.1.6'
+    id 'org.graalvm.buildtools.native' version '0.10.3'
+    id 'com.google.protobuf' version '0.9.4'
+}
+
+group = 'com.example'
+version = '0.3.0-SNAPSHOT'
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(17)
+    }
+}
+
+repositories {
+    mavenLocal()
+    mavenCentral()
+    maven { url 'https://repo.spring.io/milestone' }
+    maven { url 'https://repo.spring.io/snapshot' }
+}
+
+dependencyManagement {
+    imports {
+        mavenBom 'org.springframework.grpc:spring-grpc-dependencies:0.3.0-SNAPSHOT'
+    }
+}
+
+dependencies {
+    implementation 'org.springframework.grpc:spring-grpc-spring-boot-starter'
+    implementation 'org.springframework.boot:spring-boot-starter-webflux'
+    implementation 'io.grpc:grpc-services'
+    testImplementation 'org.springframework.boot:spring-boot-starter-test'
+    testImplementation 'org.springframework.grpc:spring-grpc-test'
+    testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
+}
+
+tasks.named('test') {
+    useJUnitPlatform()
+}
+
+protobuf {
+    protoc {
+        artifact = "com.google.protobuf:protoc:${dependencyManagement.importedProperties['protobuf-java.version']}"
+    }
+    plugins {
+        grpc {
+            artifact = "io.grpc:protoc-gen-grpc-java:${dependencyManagement.importedProperties['grpc.version']}"
+        }
+    }
+    generateProtoTasks {
+        all()*.plugins {
+            grpc {
+                option 'jakarta_omit'
+                option '@generated=omit'
+            }
+        }
+    }
+}

samples/grpc-webflux/gradle/wrapper/gradle-wrapper.jar

@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.10.2-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists