Support for @LocalGrpcPort in @Lazy beans

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

@@ -10,13 +10,15 @@ import org.springframework.boot.SpringApplication;
 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
+@SpringBootTest(properties = "spring.grpc.server.port=0")
 public class GrpcServerApplicationTests {
 
 	private static Log log = LogFactory.getLog(GrpcServerApplicationTests.class);
@@ -45,8 +47,9 @@ public class GrpcServerApplicationTests {
 	static class ExtraConfiguration {
 
 		@Bean
-		SimpleGrpc.SimpleBlockingStub stub(GrpcChannelFactory channels) {
-			return SimpleGrpc.newBlockingStub(channels.createChannel("0.0.0.0:9090").build());
+		@Lazy
+		SimpleGrpc.SimpleBlockingStub stub(GrpcChannelFactory channels, @LocalGrpcPort int port) {
+			return SimpleGrpc.newBlockingStub(channels.createChannel("0.0.0.0:" + port).build());
 		}
 
 	}

spring-grpc-core/src/main/java/org/springframework/grpc/client/GrpcChannelConfigurer.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.grpc.client;
+
+import java.util.Objects;
+import java.util.function.Consumer;
+
+import io.grpc.ManagedChannelBuilder;
+
+@FunctionalInterface
+public interface GrpcChannelConfigurer extends Consumer<ManagedChannelBuilder<?>> {
+
+	@Override
+	default GrpcChannelConfigurer andThen(final Consumer<? super ManagedChannelBuilder<?>> after) {
+		Objects.requireNonNull(after);
+		return t -> {
+			accept(t);
+			after.accept(t);
+		};
+	}
+
+}

spring-grpc-core/src/main/java/org/springframework/grpc/server/lifecycle/GrpcServerLifecycle.java

@@ -103,6 +103,10 @@ public class GrpcServerLifecycle implements SmartLifecycle {
 		return true;
 	}
 
+	public int getPort() {
+		return this.server == null ? 0 : this.server.getPort();
+	}
+
 	/**
 	 * Creates and starts the grpc server.
 	 * @throws IOException If the server is unable to bind the port.

spring-grpc-test/src/main/java/org/springframework/grpc/test/LocalGrpcPort.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.grpc.test;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.springframework.beans.factory.annotation.Value;
+
+@Target({ ElementType.FIELD, ElementType.METHOD, ElementType.PARAMETER, ElementType.ANNOTATION_TYPE })
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+@Value("${local.grpc.port}")
+public @interface LocalGrpcPort {
+
+}

spring-grpc-test/src/main/java/org/springframework/grpc/test/ServerPortInfoApplicationContextInitializer.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.grpc.test;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.ApplicationListener;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.core.env.ConfigurableEnvironment;
+import org.springframework.core.env.MapPropertySource;
+import org.springframework.core.env.MutablePropertySources;
+import org.springframework.core.env.PropertySource;
+import org.springframework.grpc.server.lifecycle.GrpcServerStartedEvent;
+
+public class ServerPortInfoApplicationContextInitializer implements
+		ApplicationContextInitializer<ConfigurableApplicationContext>, ApplicationListener<GrpcServerStartedEvent> {
+
+	private static final String PROPERTY_SOURCE_NAME = "grpc.server.ports";
+
+	private ConfigurableApplicationContext applicationContext;
+
+	@Override
+	public void initialize(ConfigurableApplicationContext applicationContext) {
+		this.applicationContext = applicationContext;
+		applicationContext.addApplicationListener(this);
+	}
+
+	@Override
+	public void onApplicationEvent(GrpcServerStartedEvent event) {
+		String propertyName = "local.grpc.port";
+		setPortProperty(applicationContext, propertyName, event.getPort());
+	}
+
+	private void setPortProperty(ApplicationContext context, String propertyName, int port) {
+		if (context instanceof ConfigurableApplicationContext configurableContext) {
+			setPortProperty(configurableContext.getEnvironment(), propertyName, port);
+		}
+		if (context.getParent() != null) {
+			setPortProperty(context.getParent(), propertyName, port);
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	private void setPortProperty(ConfigurableEnvironment environment, String propertyName, int port) {
+		MutablePropertySources sources = environment.getPropertySources();
+		PropertySource<?> source = sources.get(PROPERTY_SOURCE_NAME);
+		if (source == null) {
+			source = new MapPropertySource(PROPERTY_SOURCE_NAME, new HashMap<>());
+			sources.addFirst(source);
+		}
+		((Map<String, Object>) source.getSource()).put(propertyName, port);
+	}
+
+}

spring-grpc-test/src/main/resources/META-INF/spring.factories

@@ -0,0 +1,3 @@
+# Application Context Initializers
+org.springframework.context.ApplicationContextInitializer=\
+org.springframework.grpc.test.ServerPortInfoApplicationContextInitializer