DATAMONGO-442 - Polishing.

Reformat code according to Spring Data style. Add test for authenticated use. Add JavaDoc to newly introduced methods. Allow configuration of an authentication database. Update reference documentation.

Original pull request: #419.

spring-data-mongodb-log4j/src/main/java/org/springframework/data/mongodb/log4j/MongoLog4jAppender.java

@@ -15,15 +15,27 @@
  */
 package org.springframework.data.mongodb.log4j;
 
-import com.mongodb.*;
+import java.net.UnknownHostException;
+import java.util.Arrays;
+import java.util.Calendar;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+
 import org.apache.log4j.AppenderSkeleton;
 import org.apache.log4j.Level;
 import org.apache.log4j.MDC;
 import org.apache.log4j.PatternLayout;
 import org.apache.log4j.spi.LoggingEvent;
 
-import java.net.UnknownHostException;
+import com.mongodb.BasicDBList;
-import java.util.*;
+import com.mongodb.BasicDBObject;
+import com.mongodb.DB;
+import com.mongodb.Mongo;
+import com.mongodb.MongoClient;
+import com.mongodb.MongoCredential;
+import com.mongodb.ServerAddress;
+import com.mongodb.WriteConcern;
 
 /**
  * Log4j appender writing log entries into a MongoDB instance.
@@ -51,6 +63,7 @@ public class MongoLog4jAppender extends AppenderSkeleton {
 	protected int port = 27017;
 	protected String username;
 	protected String password;
+	protected String authenticationDatabase;
 	protected String database = "logs";
 	protected String collectionPattern = "%c";
 	protected PatternLayout collectionLayout = new PatternLayout(collectionPattern);
@@ -60,8 +73,7 @@ public class MongoLog4jAppender extends AppenderSkeleton {
 	protected Mongo mongo;
 	protected DB db;
 
-	public MongoLog4jAppender() {
+	public MongoLog4jAppender() {}
-	}
 
 	public MongoLog4jAppender(boolean isActive) {
 		super(isActive);
@@ -83,22 +95,53 @@ public class MongoLog4jAppender extends AppenderSkeleton {
 		this.port = port;
 	}
 
-	public String getPassword() {
+	/**
-		return password;
+	 * @return
-	}
+	 * @since 1.10
-
+	 */
-	public void setPassword(String password) {
-		this.password = password;
-	}
-
 	public String getUsername() {
 		return username;
 	}
 
+	/**
+	 * @param username may be {@literal null} for unauthenticated access.
+	 * @since 1.10
+	 */
 	public void setUsername(String username) {
 		this.username = username;
 	}
 
+	/**
+	 * @return
+	 * @since 1.10
+	 */
+	public String getPassword() {
+		return password;
+	}
+
+	/**
+	 * @param password may be {@literal null} for unauthenticated access.
+	 * @since 1.10
+	 */
+	public void setPassword(String password) {
+		this.password = password;
+	}
+
+	/**
+	 * @return
+	 */
+	public String getAuthenticationDatabase() {
+		return authenticationDatabase;
+	}
+
+	/**
+	 * @param authenticationDatabase may be {@literal null} to use {@link #getDatabase()} as authentication database.
+	 * @since 1.10
+	 */
+	public void setAuthenticationDatabase(String authenticationDatabase) {
+		this.authenticationDatabase = authenticationDatabase;
+	}
+
 	public String getDatabase() {
 		return database;
 	}
@@ -141,26 +184,33 @@ public class MongoLog4jAppender extends AppenderSkeleton {
 	}
 
 	protected void connectToMongo() throws UnknownHostException {
-		ServerAddress serverAddress = new ServerAddress(host, port);
+
-		connectToMongoHandlingCredentials(serverAddress);
+		this.mongo = createMongoClient();
 		this.db = mongo.getDB(database);
 	}
 
-	private void connectToMongoHandlingCredentials(ServerAddress serverAddress) {
+	private MongoClient createMongoClient() throws UnknownHostException {
+
+		ServerAddress serverAddress = new ServerAddress(host, port);
+
 		if (null == password || null == username) {
-			this.mongo = new MongoClient(serverAddress);
+			return new MongoClient(serverAddress);
-		} else {
-			MongoCredential mongoCredential = MongoCredential.createCredential(username, database, password.toCharArray());
-			List<MongoCredential> credentials = Collections.singletonList(mongoCredential);
-			this.mongo = new MongoClient(serverAddress, credentials);
 		}
+
+		String authenticationDatabaseToUse = authenticationDatabase == null ? this.database : authenticationDatabase;
+		MongoCredential mongoCredential = MongoCredential.createCredential(username,
+				authenticationDatabaseToUse, password.toCharArray());
+		List<MongoCredential> credentials = Collections.singletonList(mongoCredential);
+		return new MongoClient(serverAddress, credentials);
 	}
 
 	/*
 	 * (non-Javadoc)
 	 * @see org.apache.log4j.AppenderSkeleton#append(org.apache.log4j.spi.LoggingEvent)
 	 */
-	@Override @SuppressWarnings({ "unchecked" }) protected void append(final LoggingEvent event) {
+	@Override
+	@SuppressWarnings({ "unchecked" })
+	protected void append(final LoggingEvent event) {
 		if (null == db) {
 			try {
 				connectToMongo();

spring-data-mongodb-log4j/src/test/java/org/springframework/data/mongodb/log4j/MongoLog4jAppenderAuthenticationIntegrationTests.java

@@ -0,0 +1,114 @@
+/*
+ * Copyright 2016 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.mongodb.log4j;
+
+import static org.hamcrest.Matchers.*;
+import static org.junit.Assert.*;
+
+import java.util.Calendar;
+import java.util.Collections;
+
+import org.apache.log4j.LogManager;
+import org.apache.log4j.Logger;
+import org.apache.log4j.MDC;
+import org.apache.log4j.PropertyConfigurator;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.mongodb.BasicDBList;
+import com.mongodb.BasicDBObject;
+import com.mongodb.BasicDBObjectBuilder;
+import com.mongodb.DB;
+import com.mongodb.DBCursor;
+import com.mongodb.MongoClient;
+import com.mongodb.MongoCredential;
+import com.mongodb.ServerAddress;
+
+/**
+ * Integration tests for {@link MongoLog4jAppender} using authentication.
+ *
+ * @author Mark Paluch
+ */
+public class MongoLog4jAppenderAuthenticationIntegrationTests {
+
+	private final static String username = "admin";
+	private final static String password = "test";
+	private final static String authenticationDatabase = "logs";
+
+	MongoClient mongo;
+	DB db;
+	String collection;
+	ServerAddress serverLocation;
+
+	Logger log;
+
+	@Before
+	public void setUp() throws Exception {
+
+		serverLocation = new ServerAddress("localhost", 27017);
+
+		mongo = new MongoClient(serverLocation);
+		db = mongo.getDB("logs");
+
+		BasicDBList roles = new BasicDBList();
+		roles.add("dbOwner");
+		db.command(new BasicDBObjectBuilder().add("createUser", username).add("pwd", password).add("roles", roles).get());
+		mongo.close();
+
+		mongo = new MongoClient(serverLocation, Collections
+				.singletonList(MongoCredential.createCredential(username, authenticationDatabase, password.toCharArray())));
+		db = mongo.getDB("logs");
+
+		Calendar now = Calendar.getInstance();
+		collection = String.valueOf(now.get(Calendar.YEAR)) + String.format("%1$02d", now.get(Calendar.MONTH) + 1);
+
+		LogManager.resetConfiguration();
+		PropertyConfigurator.configure(getClass().getResource("/log4j-with-authentication.properties"));
+
+		log = Logger.getLogger(MongoLog4jAppenderIntegrationTests.class.getName());
+	}
+
+	@After
+	public void tearDown() {
+
+		if (db != null) {
+			db.getCollection(collection).remove(new BasicDBObject());
+			db.command(new BasicDBObject("dropUser", username));
+		}
+
+		LogManager.resetConfiguration();
+		PropertyConfigurator.configure(getClass().getResource("/log4j.properties"));
+	}
+
+	@Test
+	public void testLogging() {
+
+		log.debug("DEBUG message");
+		log.info("INFO message");
+		log.warn("WARN message");
+		log.error("ERROR message");
+
+		DBCursor msgs = db.getCollection(collection).find();
+		assertThat(msgs.count(), is(4));
+	}
+
+	@Test
+	public void testProperties() {
+		MDC.put("property", "one");
+		log.debug("DEBUG message");
+	}
+}

spring-data-mongodb-log4j/src/test/java/org/springframework/data/mongodb/log4j/MongoLog4jAppenderIntegrationTests.java

@@ -15,19 +15,24 @@
  */
 package org.springframework.data.mongodb.log4j;
 
-import com.mongodb.*;
+import static org.hamcrest.Matchers.*;
+import static org.junit.Assert.*;
+
+import java.util.Calendar;
+
+import org.apache.log4j.LogManager;
 import org.apache.log4j.Logger;
 import org.apache.log4j.MDC;
+import org.apache.log4j.PropertyConfigurator;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 
-import java.net.UnknownHostException;
+import com.mongodb.BasicDBObject;
-import java.util.Calendar;
+import com.mongodb.DB;
-import java.util.Collections;
+import com.mongodb.DBCursor;
-
+import com.mongodb.MongoClient;
-import static org.hamcrest.Matchers.is;
+import com.mongodb.ServerAddress;
-import static org.junit.Assert.assertThat;
 
 /**
  * Integration tests for {@link MongoLog4jAppender}.
@@ -38,13 +43,14 @@ import static org.junit.Assert.assertThat;
  */
 public class MongoLog4jAppenderIntegrationTests {
 
-	private static final Logger log = Logger.getLogger(MongoLog4jAppenderIntegrationTests.class.getName());
+	MongoClient mongo;
-	private MongoClient mongo;
+	DB db;
-	private DB db;
+	String collection;
-	private String collection;
+	ServerAddress serverLocation;
-	private ServerAddress serverLocation;
+	Logger log;
 
-	@Before public void setUp() throws Exception {
+	@Before
+	public void setUp() throws Exception {
 		serverLocation = new ServerAddress("localhost", 27017);
 
 		mongo = new MongoClient(serverLocation);
@@ -52,13 +58,18 @@ public class MongoLog4jAppenderIntegrationTests {
 
 		Calendar now = Calendar.getInstance();
 		collection = String.valueOf(now.get(Calendar.YEAR)) + String.format("%1$02d", now.get(Calendar.MONTH) + 1);
+
+		log = Logger.getLogger(MongoLog4jAppenderIntegrationTests.class.getName());
 	}
 
-	@After public void tearDown() {
+	@After
+	public void tearDown() {
 		db.getCollection(collection).remove(new BasicDBObject());
 	}
 
-	@Test public void testLogging() {
+	@Test
+	public void testLogging() {
+
 		log.debug("DEBUG message");
 		log.info("INFO message");
 		log.warn("WARN message");
@@ -68,18 +79,9 @@ public class MongoLog4jAppenderIntegrationTests {
 		assertThat(msgs.count(), is(4));
 	}
 
-	/**
+	@Test
-	 * @see DATAMONGO-442
+	public void testProperties() {
-	 */
-	@Test public void testLoggingWithCredentials() throws UnknownHostException {
-		MongoCredential credential = MongoCredential.createCredential("username", "logs", "password".toCharArray());
-		mongo = new MongoClient(serverLocation, Collections.singletonList(credential));
-		testLogging();
-	}
-
-	@Test public void testProperties() {
 		MDC.put("property", "one");
 		log.debug("DEBUG message");
 	}
-
 }

spring-data-mongodb-log4j/src/test/resources/log4j-with-authentication.properties

@@ -0,0 +1,16 @@
+log4j.rootCategory=INFO, mongo
+
+log4j.appender.mongo=org.springframework.data.mongodb.log4j.MongoLog4jAppender
+log4j.appender.mongo.layout=org.apache.log4j.PatternLayout
+log4j.appender.mongo.layout.ConversionPattern=%d %p [%c] - <%m>%n
+log4j.appender.mongo.host = localhost
+log4j.appender.mongo.port = 27017
+log4j.appender.mongo.database = logs
+log4j.appender.mongo.username = admin
+log4j.appender.mongo.password = test
+log4j.appender.mongo.authenticationDatabase = logs
+log4j.appender.mongo.collectionPattern = %X{year}%X{month}
+log4j.appender.mongo.applicationId = my.application
+log4j.appender.mongo.warnOrHigherWriteConcern = FSYNC_SAFE
+
+log4j.category.org.springframework.data.mongodb=DEBUG

spring-data-mongodb-log4j/src/test/resources/log4j.properties

@@ -1,13 +1,13 @@
-log4j.rootCategory=INFO, stdout
+log4j.rootCategory=INFO, mongo
 
-log4j.appender.stdout=org.springframework.data.mongodb.log4j.MongoLog4jAppender
+log4j.appender.mongo=org.springframework.data.mongodb.log4j.MongoLog4jAppender
-log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
+log4j.appender.mongo.layout=org.apache.log4j.PatternLayout
-log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] - <%m>%n
+log4j.appender.mongo.layout.ConversionPattern=%d %p [%c] - <%m>%n
-log4j.appender.stdout.host = localhost
+log4j.appender.mongo.host = localhost
-log4j.appender.stdout.port = 27017
+log4j.appender.mongo.port = 27017
-log4j.appender.stdout.database = logs
+log4j.appender.mongo.database = logs
-log4j.appender.stdout.collectionPattern = %X{year}%X{month}
+log4j.appender.mongo.collectionPattern = %X{year}%X{month}
-log4j.appender.stdout.applicationId = my.application
+log4j.appender.mongo.applicationId = my.application
-log4j.appender.stdout.warnOrHigherWriteConcern = FSYNC_SAFE
+log4j.appender.mongo.warnOrHigherWriteConcern = FSYNC_SAFE
 
 log4j.category.org.springframework.data.mongodb=DEBUG

src/main/asciidoc/reference/logging.adoc

@@ -10,17 +10,17 @@ Here is an example configuration
 
 [source]
 ----
-log4j.rootCategory=INFO, stdout
+log4j.rootCategory=INFO, mongo
 
-log4j.appender.stdout=org.springframework.data.document.mongodb.log4j.MongoLog4jAppender
+log4j.appender.mongo=org.springframework.data.document.mongodb.log4j.MongoLog4jAppender
-log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
+log4j.appender.mongo.layout=org.apache.log4j.PatternLayout
-log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] - <%m>%n
+log4j.appender.mongo.layout.ConversionPattern=%d %p [%c] - <%m>%n
-log4j.appender.stdout.host = localhost
+log4j.appender.mongo.host = localhost
-log4j.appender.stdout.port = 27017
+log4j.appender.mongo.port = 27017
-log4j.appender.stdout.database = logs
+log4j.appender.mongo.database = logs
-log4j.appender.stdout.collectionPattern = %X{year}%X{month}
+log4j.appender.mongo.collectionPattern = %X{year}%X{month}
-log4j.appender.stdout.applicationId = my.application
+log4j.appender.mongo.applicationId = my.application
-log4j.appender.stdout.warnOrHigherWriteConcern = FSYNC_SAFE
+log4j.appender.mongo.warnOrHigherWriteConcern = FSYNC_SAFE
 
 log4j.category.org.apache.activemq=ERROR
 log4j.category.org.springframework.batch=DEBUG
@@ -28,6 +28,23 @@ log4j.category.org.springframework.data.document.mongodb=DEBUG
 log4j.category.org.springframework.transaction=INFO
 ----
 
-The important configuration to look at aside from host and port is the database and collectionPattern. The variables year, month, day and hour are available for you to use in forming a collection name. This is to support the common convention of grouping log information in a collection that corresponds to a specific time period, for example a collection per day.
+The important configuration to look at aside from host and port is the database and `collectionPattern`. The variables `year`, `month`, `day` and `hour` are available for you to use in forming a collection name. This is to support the common convention of grouping log information in a collection that corresponds to a specific time period, for example a collection per day.
 
-There is also an applicationId which is put into the stored message. The document stored from logging as the following keys: level, name, applicationId, timestamp, properties, traceback, and message.
+There is also an `applicationId` which is put into the stored message. The document stored from logging as the following keys: `level`, `name`, `applicationId`, `timestamp`, `properties`, `traceback`, and `message`.
+
+[[mongodb:logging-configuration:authentication]]
+=== Using authentication
+
+The MongoDB Log4j appender can be configured to use username/password authentication.
+Authentication is performed using the specified database. A different `authenticationDatabase` can be specified to override the default behavior.
+
+[source]
+----
+# ...
+log4j.appender.mongo.username = admin
+log4j.appender.mongo.password = test
+log4j.appender.mongo.authenticationDatabase = logs
+# ...
+----
+
+NOTE: Authentication failures lead to exceptions during logging and are propagated to the caller of the logging method.