Allow port=0 for ApacheDSContainer

Fixes gh-8144

ldap/src/integration-test/java/org/springframework/security/ldap/server/ApacheDSContainerTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -39,6 +39,7 @@ import org.springframework.util.FileCopyUtils;
  * @author Luke Taylor
  * @author Rob Winch
  * @author Gunnar Hillert
+ * @author Evgeniy Cheban
  * @since 3.0
  */
 public class ApacheDSContainerTests {
@@ -212,4 +213,20 @@ public class ApacheDSContainerTests {
 			}
 		}
 	}
+
+	@Test
+	public void afterPropertiesSetWhenPortIsZeroThenRandomPortIsSelected() throws Exception {
+		ApacheDSContainer server = new ApacheDSContainer("dc=springframework,dc=org",
+				"classpath:test-server.ldif");
+		server.setPort(0);
+		try {
+			server.afterPropertiesSet();
+
+			assertThat(server.getPort()).isEqualTo(0);
+			assertThat(server.getLocalPort()).isNotEqualTo(0);
+		}
+		finally {
+			server.destroy();
+		}
+	}
 }

ldap/src/main/java/org/springframework/security/ldap/server/ApacheDSContainer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -15,6 +15,7 @@
  */
 package org.springframework.security.ldap.server;
 
+import java.net.InetSocketAddress;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -39,6 +40,7 @@ import org.apache.directory.server.protocol.shared.store.LdifFileLoader;
 import org.apache.directory.server.protocol.shared.transport.TcpTransport;
 import org.apache.directory.shared.ldap.exception.LdapNameNotFoundException;
 import org.apache.directory.shared.ldap.name.LdapDN;
+import org.apache.mina.transport.socket.SocketAcceptor;
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.beans.factory.InitializingBean;
@@ -69,6 +71,7 @@ import org.springframework.util.Assert;
  * @author Luke Taylor
  * @author Rob Winch
  * @author Gunnar Hillert
+ * @author Evgeniy Cheban
  * @deprecated Use {@link UnboundIdContainer} instead because ApacheDS 1.x is no longer
  * supported with no GA version to replace it.
  */
@@ -80,6 +83,7 @@ public class ApacheDSContainer implements InitializingBean, DisposableBean, Life
 	final DefaultDirectoryService service;
 	LdapServer server;
 
+	private TcpTransport transport;
 	private ApplicationContext ctxt;
 	private File workingDir;
 
@@ -88,6 +92,7 @@ public class ApacheDSContainer implements InitializingBean, DisposableBean, Life
 	private final JdbmPartition partition;
 	private final String root;
 	private int port = 53389;
+	private int localPort;
 
 	private boolean ldapOverSslEnabled;
 	private File keyStoreFile;
@@ -143,7 +148,7 @@ public class ApacheDSContainer implements InitializingBean, DisposableBean, Life
 		server.setDirectoryService(service);
 		// AbstractLdapIntegrationTests assume IPv4, so we specify the same here
 
-		TcpTransport transport = new TcpTransport(port);
+		this.transport = new TcpTransport(port);
 		if (ldapOverSslEnabled) {
 				transport.setEnableSSL(true);
 				server.setKeystoreFile(this.keyStoreFile.getAbsolutePath());
@@ -190,6 +195,15 @@ public class ApacheDSContainer implements InitializingBean, DisposableBean, Life
 		return this.port;
 	}
 
+	/**
+	 * Returns the port that is resolved by {@link TcpTransport}.
+	 *
+	 * @return the port that is resolved by {@link TcpTransport}
+	 */
+	public int getLocalPort() {
+		return this.localPort;
+	}
+
 	/**
 	 * If set to {@code true} will enable LDAP over SSL (LDAPs). If set to {@code true}
 	 * {@link ApacheDSContainer#setCertificatePassord(String)} must be set as well.
@@ -262,6 +276,10 @@ public class ApacheDSContainer implements InitializingBean, DisposableBean, Life
 			logger.error("Lookup failed", e);
 		}
 
+		SocketAcceptor socketAcceptor = this.server.getSocketAcceptor(this.transport);
+		InetSocketAddress localAddress = socketAcceptor.getLocalAddress();
+		this.localPort = localAddress.getPort();
+
 		running = true;
 
 		try {