support random port assignment in AbstractDiscoveryLifecycle

spring-cloud-commons/src/main/java/org/springframework/cloud/client/discovery/AbstractDiscoveryLifecycle.java

@@ -21,21 +21,26 @@ import javax.annotation.PreDestroy;
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.boot.actuate.autoconfigure.ManagementServerProperties;
+import org.springframework.boot.context.embedded.EmbeddedServletContainerInitializedEvent;
 import org.springframework.cloud.client.discovery.event.InstanceRegisteredEvent;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
+import org.springframework.context.ApplicationListener;
 import org.springframework.core.env.Environment;
 
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+
 /**
  * Lifecycle methods that may be useful and common to various DiscoveryClient implementations.
  * @author Spencer Gibb
  */
 public abstract class AbstractDiscoveryLifecycle implements DiscoveryLifecycle,
-		ApplicationContextAware {
+		ApplicationContextAware, ApplicationListener<EmbeddedServletContainerInitializedEvent> {
 
 	private boolean autoStartup = true;
 
-	private boolean running;
+	private AtomicBoolean running = new AtomicBoolean(false);
 
 	private int order = 0;
 
@@ -43,6 +48,8 @@ public abstract class AbstractDiscoveryLifecycle implements DiscoveryLifecycle,
 
 	private Environment environment;
 
+	private AtomicInteger port = new AtomicInteger(0);
+
 	protected ApplicationContext getContext() {
 		return context;
 	}
@@ -58,6 +65,10 @@ public abstract class AbstractDiscoveryLifecycle implements DiscoveryLifecycle,
 		return environment;
 	}
 
+	protected AtomicInteger getPort() {
+		return port;
+	}
+
 	@Override
 	public boolean isAutoStartup() {
 		return this.autoStartup;
@@ -75,15 +86,26 @@ public abstract class AbstractDiscoveryLifecycle implements DiscoveryLifecycle,
 			return;
 		}
 
-		register();
-		if (shouldRegisterManagement()) {
-			registerManagement();
+		// only set the port if the nonSecurePort is 0 and this.port != 0
+		if (this.port.get() != 0 && getConfiguredPort() == 0) {
+			setConfiguredPort(this.port.get());
+		}
+		// only initialize if nonSecurePort is greater than 0 and it isn't already running
+		// because of containerPortInitializer below
+		if (!this.running.get() && getConfiguredPort() > 0) {
+			register();
+			if (shouldRegisterManagement()) {
+				registerManagement();
+			}
+			this.context .publishEvent(new InstanceRegisteredEvent<>(this,
+					getConfiguration()));
+			this.running.compareAndSet(false, true);
 		}
-		this.context
-				.publishEvent(new InstanceRegisteredEvent<>(this, getConfiguration()));
-		this.running = true;
 	}
 
+	protected abstract int getConfiguredPort();
+	protected abstract void setConfiguredPort(int port);
+
 	/**
 	 * @return if the management service should be registered with the DiscoveryService
 	 */
@@ -171,7 +193,7 @@ public abstract class AbstractDiscoveryLifecycle implements DiscoveryLifecycle,
 				deregisterManagement();
 			}
 		}
-		this.running = false;
+		this.running.compareAndSet(true, false);
 	}
 
 	@PreDestroy
@@ -181,7 +203,7 @@ public abstract class AbstractDiscoveryLifecycle implements DiscoveryLifecycle,
 
 	@Override
 	public boolean isRunning() {
-		return this.running;
+		return this.running.get();
 	}
 
 	@Override
@@ -194,4 +216,10 @@ public abstract class AbstractDiscoveryLifecycle implements DiscoveryLifecycle,
 		return 0;
 	}
 
+	@Override
+	public void onApplicationEvent(EmbeddedServletContainerInitializedEvent event) {
+		// TODO: take SSL into account when Spring Boot 1.2 is available
+		this.port.compareAndSet(0, event.getEmbeddedServletContainer().getPort());
+		this.start();
+	}
 }

spring-cloud-commons/src/test/java/org/springframework/cloud/client/discovery/AbstractDiscoveryLifecycleTests.java

@@ -0,0 +1,85 @@
+package org.springframework.cloud.client.discovery;
+
+import static org.junit.Assert.*;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.test.SpringApplicationConfiguration;
+import org.springframework.boot.test.WebIntegrationTest;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+/**
+ * @author Spencer Gibb
+ */
+@RunWith(SpringJUnit4ClassRunner.class)
+@SpringApplicationConfiguration(classes = AbstractDiscoveryLifecycleTests.Config.class)
+@WebIntegrationTest(randomPort = true)
+public class AbstractDiscoveryLifecycleTests {
+
+	@Autowired
+	private TestDiscoveryLifecycle lifecycle;
+
+	@Test
+	public void randomPortWorks() {
+		assertNotEquals("Lifecycle port is zero", 0, lifecycle.getPort().get());
+		assertTrue("Lifecycle not running", lifecycle.isRunning());
+		assertTrue("Lifecycle not registered", lifecycle.isRegistered());
+	}
+
+	@EnableAutoConfiguration
+	@Configuration
+	public static class Config {
+		@Bean
+		public TestDiscoveryLifecycle testDiscoveryLifecycle() {
+			return new TestDiscoveryLifecycle();
+		}
+	}
+
+	public static class TestDiscoveryLifecycle extends AbstractDiscoveryLifecycle {
+		private int port = 0;
+		private boolean registered = false;
+		private boolean deregistered = false;
+
+		@Override
+		protected int getConfiguredPort() {
+			return port;
+		}
+
+		@Override
+		protected void setConfiguredPort(int port) {
+			this.port = port;
+		}
+
+		@Override
+		protected Object getConfiguration() {
+			return this;
+		}
+
+		@Override
+		protected void register() {
+			this.registered = true;
+		}
+
+		@Override
+		protected void deregister() {
+			this.deregistered = true;
+		}
+
+		@Override
+		protected boolean isEnabled() {
+			return true;
+		}
+
+		public boolean isRegistered() {
+			return registered;
+		}
+
+		public boolean isDeregistered() {
+			return deregistered;
+		}
+	}
+}