random grpc port support

Author: Alexander Furer

grpc-spring-boot-starter/src/main/java/org/lognet/springboot/grpc/GRpcServerRunner.java

@@ -5,6 +5,7 @@
 import io.grpc.services.HealthStatusManager;
 import lombok.extern.slf4j.Slf4j;
 import org.lognet.springboot.grpc.autoconfigure.GRpcServerProperties;
+import org.lognet.springboot.grpc.context.GRpcServerInitializedEvent;
 import org.springframework.beans.factory.BeanCreationException;
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -81,23 +82,14 @@ public void run(String... args) throws Exception {
 
         configurer.configure(serverBuilder);
         server = serverBuilder.build().start();
+        applicationContext.publishEvent(new GRpcServerInitializedEvent(server));
 
         log.info("gRPC Server started, listening on port {}.", server.getPort());
         startDaemonAwaitThread();
 
     }
 
-    /**
-     * Return the port the server is actually running on.
-     *
-     * @return the port the server is actually running on or 0, if the server is not initialized yet
-     */
-    public int getRunningPort() {
-        if (server == null) {
-            return 0;
-        }
-        return server.getPort();
-    }
+
 
     private ServerServiceDefinition bindInterceptors(ServerServiceDefinition serviceDefinition, GRpcService gRpcService, Collection<ServerInterceptor> globalInterceptors) {
 

grpc-spring-boot-starter/src/main/java/org/lognet/springboot/grpc/autoconfigure/GRpcAutoConfiguration.java

@@ -44,23 +44,7 @@ public class GRpcAutoConfiguration {
     @Bean
     @ConditionalOnProperty(value = "grpc.enabled", havingValue = "true", matchIfMissing = true)
     public GRpcServerRunner grpcServerRunner(GRpcServerBuilderConfigurer configurer) {
-        int port = grpcServerProperties.getPort();
-
-        GRpcServerRunner gRpcServerRunner = new GRpcServerRunner(configurer, ServerBuilder.forPort(port));
-
-        if (applicationContext instanceof ConfigurableApplicationContext) {
-            int runningPort = gRpcServerRunner.getRunningPort();
-
-            MutablePropertySources sources = ((ConfigurableApplicationContext) applicationContext).getEnvironment().getPropertySources();
-            PropertySource<?> source = sources.get("server.ports");
-            if (source == null) {
-                source = new MapPropertySource("server.ports", new HashMap<String, Object>());
-                sources.addFirst(source);
-            }
-            ((Map<String, Object>) source.getSource()).put("local.grpc.port", runningPort);
-        }
-
-        return gRpcServerRunner;
+        return new GRpcServerRunner(configurer, ServerBuilder.forPort(grpcServerProperties.getPort()));
     }
 
     @Bean

grpc-spring-boot-starter/src/main/java/org/lognet/springboot/grpc/autoconfigure/GRpcServerProperties.java

@@ -20,13 +20,6 @@ public class GRpcServerProperties {
      */
     private int port = 6565;
 
-    public int getPort() {
-        if (port == 0) {
-            port = SocketUtils.findAvailableTcpPort(40000, 50000);
-        }
-        return port;
-    }
-
     /**
      * Enables the embedded grpc server.
      */

grpc-spring-boot-starter/src/main/java/org/lognet/springboot/grpc/context/GRpcServerInitializedEvent.java

@@ -0,0 +1,18 @@
+package org.lognet.springboot.grpc.context;
+
+import io.grpc.Server;
+import org.springframework.context.ApplicationEvent;
+
+public class GRpcServerInitializedEvent extends ApplicationEvent {
+    /**
+     * Create a new ApplicationEvent.
+     *
+     * @param source the object on which the event initially occurred (never {@code null})
+     */
+    public GRpcServerInitializedEvent(Server source) {
+        super(source);
+    }
+    public Server getServer(){
+        return (Server) getSource();
+    }
+}

grpc-spring-boot-starter/src/main/java/org/lognet/springboot/grpc/context/GRpcServerPortInfoApplicationContextInitializer.java

@@ -0,0 +1,40 @@
+package org.lognet.springboot.grpc.context;
+
+import io.grpc.ServerBuilder;
+import org.lognet.springboot.grpc.GRpcServerRunner;
+import org.springframework.boot.context.embedded.EmbeddedServletContainerInitializedEvent;
+import org.springframework.boot.context.embedded.ServerPortInfoApplicationContextInitializer;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.ApplicationEvent;
+import org.springframework.context.ApplicationListener;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.core.env.MapPropertySource;
+import org.springframework.core.env.MutablePropertySources;
+import org.springframework.core.env.PropertySource;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class GRpcServerPortInfoApplicationContextInitializer implements ApplicationContextInitializer<ConfigurableApplicationContext> {
+    @Override
+    public void initialize(ConfigurableApplicationContext applicationContext) {
+        applicationContext.addApplicationListener(new ApplicationListener<GRpcServerInitializedEvent>() {
+            @Override
+            public void onApplicationEvent(GRpcServerInitializedEvent event) {
+                GRpcServerPortInfoApplicationContextInitializer.this.onApplicationEvent(applicationContext,event);
+            }
+        });
+    }
+
+    private void onApplicationEvent(ConfigurableApplicationContext applicationContext,GRpcServerInitializedEvent event) {
+        MutablePropertySources sources =  applicationContext.getEnvironment().getPropertySources();
+        PropertySource<?> source = sources.get("server.ports");
+        if (source == null) {
+            source = new MapPropertySource("server.ports", new HashMap<>());
+            sources.addFirst(source);
+        }
+        ((Map<String, Object>) source.getSource()).put("local.grpc.port", event.getServer().getPort());
+    }
+
+
+}

grpc-spring-boot-starter/src/main/java/org/lognet/springboot/grpc/context/LocalRunningGrpcPort.java

@@ -0,0 +1,13 @@
+package org.lognet.springboot.grpc.context;
+
+import org.springframework.beans.factory.annotation.Value;
+
+import java.lang.annotation.*;
+
+@Target({ ElementType.FIELD, ElementType.METHOD, ElementType.PARAMETER,
+        ElementType.ANNOTATION_TYPE })
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+@Value("${grpc.port !=0 ? ${grpc.port}:${local.grpc.port}}")
+public @interface LocalRunningGrpcPort {
+}

grpc-spring-boot-starter/src/main/resources/META-INF/spring.factories

@@ -1 +1,5 @@
-org.springframework.boot.autoconfigure.EnableAutoConfiguration=org.lognet.springboot.grpc.autoconfigure.GRpcAutoConfiguration
+org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
+org.lognet.springboot.grpc.autoconfigure.GRpcAutoConfiguration
+
+org.springframework.context.ApplicationContextInitializer=\
+org.lognet.springboot.grpc.context.GRpcServerPortInfoApplicationContextInitializer