Refactor random port in reactive module tests

This commit removes the use of SocketUtils#findAvailableTcpPort in
favor of letting servers pick a dynamic port by specifying port 0.

This should make integration tests more stable because the port is
chosen at the place where it needs to be used. It gives servers a
chance to try to open a socket on some port and start using the socket
if successful.

spring-web-reactive/src/test/java/org/springframework/web/reactive/result/method/annotation/ContextPathIntegrationTests.java

@@ -25,7 +25,6 @@ import org.springframework.context.annotation.Configuration;
 import org.springframework.http.server.reactive.HttpHandler;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.http.server.reactive.bootstrap.ReactorHttpServer;
-import org.springframework.util.SocketUtils;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.client.RestTemplate;
@@ -61,7 +60,6 @@ public class ContextPathIntegrationTests {
 		HttpHandler webApp2Handler = DispatcherHandler.toHttpHandler(context2);
 
 		this.server = new ReactorHttpServer();
-		this.server.setPort(SocketUtils.findAvailableTcpPort());
 
 		this.server.registerHttpHandler("/webApp1", webApp1Handler);
 		this.server.registerHttpHandler("/webApp2", webApp2Handler);

spring-web-reactive/src/test/java/org/springframework/web/reactive/socket/AbstractWebSocketIntegrationTests.java

@@ -44,7 +44,6 @@ import org.springframework.http.server.reactive.bootstrap.ReactorHttpServer;
 import org.springframework.http.server.reactive.bootstrap.RxNettyHttpServer;
 import org.springframework.http.server.reactive.bootstrap.TomcatHttpServer;
 import org.springframework.http.server.reactive.bootstrap.UndertowHttpServer;
-import org.springframework.util.SocketUtils;
 import org.springframework.web.reactive.DispatcherHandler;
 import org.springframework.web.reactive.socket.client.JettyWebSocketClient;
 import org.springframework.web.reactive.socket.client.ReactorNettyWebSocketClient;
@@ -135,12 +134,13 @@ public abstract class AbstractWebSocketIntegrationTests {
 
 		assumeFalse(this.client instanceof UndertowWebSocketClient && this.server instanceof RxNettyHttpServer);
 
-		this.port = SocketUtils.findAvailableTcpPort();
-		this.server.setPort(this.port);
 		this.server.setHandler(createHttpHandler());
 		this.server.afterPropertiesSet();
 		this.server.start();
 
+		// Set dynamically chosen port
+		this.port = this.server.getPort();
+
 		if (this.client instanceof Lifecycle) {
 			((Lifecycle) this.client).start();
 		}

spring-web/src/test/java/org/springframework/http/server/reactive/AbstractHttpHandlerIntegrationTests.java

@@ -18,6 +18,8 @@ package org.springframework.http.server.reactive;
 
 import java.io.File;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.runner.RunWith;
@@ -29,11 +31,12 @@ import org.springframework.http.server.reactive.bootstrap.ReactorHttpServer;
 import org.springframework.http.server.reactive.bootstrap.RxNettyHttpServer;
 import org.springframework.http.server.reactive.bootstrap.TomcatHttpServer;
 import org.springframework.http.server.reactive.bootstrap.UndertowHttpServer;
-import org.springframework.util.SocketUtils;
 
 @RunWith(Parameterized.class)
 public abstract class AbstractHttpHandlerIntegrationTests {
 
+	protected Log logger = LogFactory.getLog(getClass());
+
 	protected int port;
 
 	@Parameterized.Parameter(0)
@@ -55,16 +58,18 @@ public abstract class AbstractHttpHandlerIntegrationTests {
 
 	@Before
 	public void setup() throws Exception {
-		this.port = SocketUtils.findAvailableTcpPort();
-		this.server.setPort(this.port);
 		this.server.setHandler(createHttpHandler());
 		this.server.afterPropertiesSet();
 		this.server.start();
+
+		// Set dynamically chosen port
+		this.port = this.server.getPort();
 	}
 
 	@After
 	public void tearDown() throws Exception {
 		this.server.stop();
+		this.port = 0;
 	}
 
 

spring-web/src/test/java/org/springframework/http/server/reactive/bootstrap/AbstractHttpServer.java

@@ -29,7 +29,7 @@ public abstract class AbstractHttpServer implements HttpServer {
 
 	private String host = "0.0.0.0";
 
-	private int port = -1;
+	private int port = 0;
 
 	private HttpHandler httpHandler;
 
@@ -40,6 +40,7 @@ public abstract class AbstractHttpServer implements HttpServer {
 	private final Object lifecycleMonitor = new Object();
 
 
+	@Override
 	public void setHost(String host) {
 		this.host = host;
 	}
@@ -48,14 +49,17 @@ public abstract class AbstractHttpServer implements HttpServer {
 		return host;
 	}
 
+	@Override
 	public void setPort(int port) {
 		this.port = port;
 	}
 
+	@Override
 	public int getPort() {
 		return this.port;
 	}
 
+	@Override
 	public void setHandler(HttpHandler handler) {
 		this.httpHandler = handler;
 	}
@@ -138,13 +142,16 @@ public abstract class AbstractHttpServer implements HttpServer {
 		}
 	}
 
-	protected void reset() {
+	protected abstract void stopInternal() throws Exception;
+
+	private void reset() {
 		this.host = "0.0.0.0";
-		this.port = -1;
+		this.port = 0;
 		this.httpHandler = null;
 		this.handlerMap = null;
+		resetInternal();
 	}
 
-	protected abstract void stopInternal() throws Exception;
+	protected abstract void resetInternal();
 
 }

spring-web/src/test/java/org/springframework/http/server/reactive/bootstrap/HttpServer.java

@@ -29,6 +29,8 @@ public interface HttpServer extends InitializingBean, Lifecycle {
 
 	void setPort(int port);
 
+	int getPort();
+
 	void setHandler(HttpHandler handler);
 
 }

spring-web/src/test/java/org/springframework/http/server/reactive/bootstrap/JettyHttpServer.java

@@ -60,6 +60,7 @@ public class JettyHttpServer extends AbstractHttpServer {
 	@Override
 	protected void startInternal() throws Exception {
 		this.jettyServer.start();
+		setPort(((ServerConnector) this.jettyServer.getConnectors()[0]).getLocalPort());
 	}
 
 	@Override
@@ -84,8 +85,7 @@ public class JettyHttpServer extends AbstractHttpServer {
 	}
 
 	@Override
-	protected void reset() {
-		super.reset();
+	protected void resetInternal() {
 		try {
 			if (this.jettyServer.isRunning()) {
 				this.jettyServer.setStopTimeout(5000);

spring-web/src/test/java/org/springframework/http/server/reactive/bootstrap/ReactorHttpServer.java

@@ -49,7 +49,6 @@ public class ReactorHttpServer extends AbstractHttpServer implements Loopback {
 				new ReactorHttpHandlerAdapter(getHttpHandler());
 	}
 
-
 	@Override
 	public Object connectedInput() {
 		return this.reactorServer;
@@ -63,6 +62,7 @@ public class ReactorHttpServer extends AbstractHttpServer implements Loopback {
 	@Override
 	protected void startInternal() {
 		NettyContext nettyContext = this.reactorServer.newHandler(this.reactorHandler).block();
+		setPort(nettyContext.address().getPort());
 		this.nettyContext.set(nettyContext);
 	}
 
@@ -72,8 +72,7 @@ public class ReactorHttpServer extends AbstractHttpServer implements Loopback {
 	}
 
 	@Override
-	protected void reset() {
-		super.reset();
+	protected void resetInternal() {
 		this.reactorServer = null;
 		this.reactorHandler = null;
 		this.nettyContext.set(null);

spring-web/src/test/java/org/springframework/http/server/reactive/bootstrap/RxNettyHttpServer.java

@@ -37,8 +37,7 @@ public class RxNettyHttpServer extends AbstractHttpServer {
 	@Override
 	protected void initServer() throws Exception {
 		this.rxNettyHandler = createHttpHandlerAdapter();
-		this.rxNettyServer = io.reactivex.netty.protocol.http.server.HttpServer
-				.newServer(new InetSocketAddress(getHost(), getPort()));
+		this.rxNettyServer = io.reactivex.netty.protocol.http.server.HttpServer.newServer(getPort());
 	}
 
 	@NotNull
@@ -52,6 +51,7 @@ public class RxNettyHttpServer extends AbstractHttpServer {
 	@Override
 	protected void startInternal() {
 		this.rxNettyServer.start(this.rxNettyHandler);
+		setPort(this.rxNettyServer.getServerPort());
 	}
 
 	@Override
@@ -60,8 +60,7 @@ public class RxNettyHttpServer extends AbstractHttpServer {
 	}
 
 	@Override
-	protected void reset() {
-		super.reset();
+	protected void resetInternal() {
 		this.rxNettyServer = null;
 		this.rxNettyHandler = null;
 	}

spring-web/src/test/java/org/springframework/http/server/reactive/bootstrap/TomcatHttpServer.java

@@ -77,6 +77,7 @@ public class TomcatHttpServer extends AbstractHttpServer {
 	@Override
 	protected void startInternal() throws LifecycleException {
 		this.tomcatServer.start();
+		setPort(this.tomcatServer.getConnector().getLocalPort());
 	}
 
 	@Override
@@ -86,7 +87,7 @@ public class TomcatHttpServer extends AbstractHttpServer {
 	}
 
 	@Override
-	protected void reset() {
+	protected void resetInternal() {
 		this.tomcatServer = null;
 	}
 

spring-web/src/test/java/org/springframework/http/server/reactive/bootstrap/UndertowHttpServer.java

@@ -16,6 +16,8 @@
 
 package org.springframework.http.server.reactive.bootstrap;
 
+import java.net.InetSocketAddress;
+
 import io.undertow.Undertow;
 
 import org.springframework.http.server.reactive.UndertowHttpHandlerAdapter;
@@ -44,6 +46,8 @@ public class UndertowHttpServer extends AbstractHttpServer {
 	@Override
 	protected void startInternal() {
 		this.server.start();
+		Undertow.ListenerInfo info = this.server.getListenerInfo().get(0);
+		setPort(((InetSocketAddress) info.getAddress()).getPort());
 	}
 
 	@Override
@@ -52,8 +56,7 @@ public class UndertowHttpServer extends AbstractHttpServer {
 	}
 
 	@Override
-	protected void reset() {
-		super.reset();
+	protected void resetInternal() {
 		this.server = null;
 	}