Added config interceptor for in-memory server

CONTRIBUTING.adoc

@@ -81,6 +81,8 @@ The wiki pages https://github.com/spring-projects/spring-framework/wiki/Code-Sty
 
 To format the code as well as check the style, run `./gradlew format check`.
 
+Lastly, run `./gradlew checkstyleMain checkstyleTest` before submitting a pull request, for additional style checks.
+
 [[submit-a-pull-request]]
 === Submit a Pull Request
 

modules/ROOT/pages/testing.adoc

@@ -182,17 +182,19 @@ testCompile "com.unboundid:unboundid-ldapsdk:3.1.1"
 The following bean definition creates an embedded LDAP server:
 
 ====
-[source,xml]
+[source,java]
 ----
-<bean id="embeddedLdapServer" class="org.springframework.ldap.test.unboundid.EmbeddedLdapServerFactoryBean">
-    <property name="partitionName" value="example"/>
-    <property name="partitionSuffix" value="dc=261consulting,dc=com" />
-    <property name="port" value="9321" />
-</bean>
+@Bean
+EmbeddedLdapServer embeddedLdapServer() {
+    return EmbeddedLdapServer.withPartitionSuffix("dc=jayway,dc=se")
+        .partitionName("jayway")
+        .port(18881)
+        .configurationCustomizer((config) -> config.setCodeLogDetails(tempLogFile, true))
+        .build();
+}
 ----
-====
 
-`spring-ldap-test` provides a way to populate the LDAP server by using `org.springframework.ldap.test.unboundid.LdifPopulator`. To use it, create a bean similar to the following:
+Alternatively, you can use the `org.springframework.ldap.test.unboundid.LdifPopulator` to create and populate the LDAP server. To use it, create a bean similar to the following:
 
 ====
 [source,xml]

test-support/src/main/java/org/springframework/ldap/test/unboundid/EmbeddedLdapServer.java

@@ -16,6 +16,13 @@
 
 package org.springframework.ldap.test.unboundid;
 
+import java.util.List;
+import java.util.function.Consumer;
+
+import javax.naming.InvalidNameException;
+import javax.naming.ldap.LdapName;
+import javax.naming.ldap.Rdn;
+
 import com.unboundid.ldap.listener.InMemoryDirectoryServer;
 import com.unboundid.ldap.listener.InMemoryDirectoryServerConfig;
 import com.unboundid.ldap.listener.InMemoryListenerConfig;
@@ -24,6 +31,7 @@
 import com.unboundid.ldap.sdk.LDAPException;
 
 import org.springframework.util.Assert;
+import org.springframework.util.CollectionUtils;
 
 /**
  * Helper class for embedded Unboundid ldap server.
@@ -45,27 +53,30 @@ public EmbeddedLdapServer(InMemoryDirectoryServer directoryServer) {
 		this.directoryServer = directoryServer;
 	}
 
+	/**
+	 * Creates a new {@link Builder} with a given partition suffix.
+	 *
+	 * @since 3.3
+	 */
+	public static Builder withPartitionSuffix(String partitionSuffix) {
+		return new Builder(partitionSuffix);
+	}
+
 	/**
 	 * Creates and starts new embedded LDAP server.
+	 * @deprecated Use the builder pattern exposed via
+	 * {@link #withPartitionSuffix(String)} instead.
 	 */
+	@Deprecated(since = "3.3")
 	public static EmbeddedLdapServer newEmbeddedServer(String defaultPartitionName, String defaultPartitionSuffix,
 			int port) throws Exception {
-		InMemoryDirectoryServerConfig config = new InMemoryDirectoryServerConfig(defaultPartitionSuffix);
-		config.addAdditionalBindCredentials("uid=admin,ou=system", "secret");
-
-		config.setListenerConfigs(InMemoryListenerConfig.createLDAPConfig("LDAP", port));
-
-		config.setEnforceSingleStructuralObjectClass(false);
-		config.setEnforceAttributeSyntaxCompliance(true);
+		EmbeddedLdapServer server = EmbeddedLdapServer.withPartitionSuffix(defaultPartitionSuffix)
+			.partitionName(defaultPartitionName)
+			.port(port)
+			.build();
 
-		Entry entry = new Entry(new DN(defaultPartitionSuffix));
-		entry.addAttribute("objectClass", "top", "domain", "extensibleObject");
-		entry.addAttribute("dc", defaultPartitionName);
-
-		InMemoryDirectoryServer directoryServer = new InMemoryDirectoryServer(config);
-		directoryServer.add(entry);
-		directoryServer.startListening();
-		return new EmbeddedLdapServer(directoryServer);
+		server.start();
+		return server;
 	}
 
 	/**
@@ -102,4 +113,119 @@ public void shutdown() {
 		this.directoryServer.shutDown(true);
 	}
 
+	/**
+	 * Helper class for embedded Unboundid ldap server.
+	 *
+	 * @author Emanuel Trandafir
+	 * @since 3.3
+	 */
+	public static final class Builder {
+
+		private final String partitionSuffix;
+
+		private String partitionName;
+
+		private int port = 0;
+
+		private Consumer<InMemoryDirectoryServerConfig> configurationCustomizer = (__) -> {
+		};
+
+		private Builder(String partitionSuffix) {
+			this.partitionSuffix = partitionSuffix;
+			this.partitionName = leftMostElement(partitionSuffix);
+		}
+
+		/**
+		 * Sets the port for the embedded LDAP server.
+		 * @param port the port for the embedded LDAP server. Defaults to 0 in which case
+		 * the server should automatically choose an available port.
+		 * @return this {@link Builder} instance.
+		 */
+		public Builder port(int port) {
+			this.port = port;
+			return this;
+		}
+
+		/**
+		 * Sets a customizer for the {@link InMemoryDirectoryServerConfig}.
+		 * @param configurationCustomizer a {@link Consumer} function that will be applied
+		 * to the {@link InMemoryDirectoryServerConfig} before creating the
+		 * {@link InMemoryDirectoryServer}. The default values, it a Consumer function
+		 * that does nothing: (config) -> {}
+		 * @return this {@link Builder} instance.
+		 */
+		public Builder configurationCustomizer(Consumer<InMemoryDirectoryServerConfig> configurationCustomizer) {
+			this.configurationCustomizer = configurationCustomizer;
+			return this;
+		}
+
+		/**
+		 * Sets the partition name for the embedded LDAP server.
+		 * @param partitionName the partition name for the embedded LDAP server. Defaults
+		 * to the left most element of the partition suffix.
+		 * @return this {@link Builder} instance.
+		 */
+		public Builder partitionName(String partitionName) {
+			this.partitionName = partitionName;
+			return this;
+		}
+
+		/**
+		 * Builds and returns a {@link EmbeddedLdapServer}.
+		 * <p>
+		 * In order to start the server, you should call
+		 * {@link EmbeddedLdapServer#start()}.
+		 * @return a new {@link EmbeddedLdapServer}.
+		 */
+		public EmbeddedLdapServer build() {
+			try {
+				InMemoryDirectoryServerConfig config = inMemoryDirectoryServerConfig(this.partitionSuffix, this.port);
+				this.configurationCustomizer.accept(config);
+
+				Entry entry = ldapEntry(this.partitionName, this.partitionSuffix);
+				InMemoryDirectoryServer directoryServer = inMemoryDirectoryServer(config, entry);
+				return new EmbeddedLdapServer(directoryServer);
+			}
+			catch (Exception ex) {
+				throw new RuntimeException(ex);
+			}
+		}
+
+		static String leftMostElement(String partitionSuffix) {
+			try {
+				List<Rdn> rdns = new LdapName(partitionSuffix).getRdns();
+				return CollectionUtils.lastElement(rdns).getValue().toString();
+			}
+			catch (InvalidNameException ex) {
+				throw new RuntimeException(ex);
+			}
+		}
+
+		private static InMemoryDirectoryServerConfig inMemoryDirectoryServerConfig(String partitionSuffix, int port)
+				throws LDAPException {
+			InMemoryDirectoryServerConfig config = new InMemoryDirectoryServerConfig(partitionSuffix);
+			config.addAdditionalBindCredentials("uid=admin,ou=system", "secret");
+			config.setListenerConfigs(InMemoryListenerConfig.createLDAPConfig("LDAP", port));
+			config.setEnforceSingleStructuralObjectClass(false);
+			config.setEnforceAttributeSyntaxCompliance(true);
+			return config;
+		}
+
+		private static Entry ldapEntry(String defaultPartitionName, String defaultPartitionSuffix)
+				throws LDAPException {
+			Entry entry = new Entry(new DN(defaultPartitionSuffix));
+			entry.addAttribute("objectClass", "top", "domain", "extensibleObject");
+			entry.addAttribute("dc", defaultPartitionName);
+			return entry;
+		}
+
+		private static InMemoryDirectoryServer inMemoryDirectoryServer(InMemoryDirectoryServerConfig config,
+				Entry entry) throws LDAPException {
+			InMemoryDirectoryServer directoryServer = new InMemoryDirectoryServer(config);
+			directoryServer.add(entry);
+			return directoryServer;
+		}
+
+	}
+
 }

test-support/src/main/java/org/springframework/ldap/test/unboundid/EmbeddedLdapServerFactoryBean.java

@@ -48,7 +48,13 @@ public void setPort(int port) {
 
 	@Override
 	protected EmbeddedLdapServer createInstance() throws Exception {
-		return EmbeddedLdapServer.newEmbeddedServer(this.partitionName, this.partitionSuffix, this.port);
+		EmbeddedLdapServer server = EmbeddedLdapServer.withPartitionSuffix(this.partitionSuffix)
+			.partitionName(this.partitionName)
+			.port(this.port)
+			.build();
+
+		server.start();
+		return server;
 	}
 
 	@Override

test-support/src/main/java/org/springframework/ldap/test/unboundid/LdapTestUtils.java

@@ -78,7 +78,12 @@ public static void startEmbeddedServer(int port, String defaultPartitionSuffix,
 		}
 
 		try {
-			embeddedServer = EmbeddedLdapServer.newEmbeddedServer(defaultPartitionName, defaultPartitionSuffix, port);
+			embeddedServer = EmbeddedLdapServer.withPartitionSuffix(defaultPartitionSuffix)
+				.partitionName(defaultPartitionName)
+				.port(port)
+				.build();
+
+			embeddedServer.start();
 		}
 		catch (Exception ex) {
 			throw new UncategorizedLdapException("Failed to start embedded server", ex);