GUAC-914: Migrate to logback and latest SLF4J. Read logback.xml from GUACAMOLE_HOME if present.

guacamole/src/main/java/org/glyptodon/guacamole/net/basic/log/LogbackInitializer.java

@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2014 Glyptodon LLC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package org.glyptodon.guacamole.net.basic.log;
+
+import ch.qos.logback.classic.LoggerContext;
+import ch.qos.logback.classic.joran.JoranConfigurator;
+import ch.qos.logback.core.joran.spi.JoranException;
+import ch.qos.logback.core.util.StatusPrinter;
+import java.io.File;
+import javax.servlet.ServletContextEvent;
+import javax.servlet.ServletContextListener;
+import org.glyptodon.guacamole.properties.GuacamoleHome;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Initializes the logback logging subsystem, used behind SLF4J within
+ * Guacamole for all logging.
+ *
+ * @author Michael Jumper
+ */
+public class LogbackInitializer implements ServletContextListener {
+
+    /**
+     * Logger for this class.
+     */
+    private final Logger logger = LoggerFactory.getLogger(LogbackInitializer.class);
+
+    @Override
+    public void contextDestroyed(ServletContextEvent sce) {
+    }
+
+    @Override
+    public void contextInitialized(ServletContextEvent sce) {
+
+        // Only load logback configuration if GUACAMOLE_HOME exists
+        File guacamoleHome = GuacamoleHome.getDirectory();
+        if (!guacamoleHome.isDirectory())
+            return;
+
+        // Check for custom logback.xml
+        File logbackConfiguration = new File(guacamoleHome, "logback.xml");
+        if (!logbackConfiguration.exists())
+            return;
+
+        logger.info("Loading logback configuration from \"{}\".", logbackConfiguration);
+        
+        LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
+        try {
+
+            // Initialize logback
+            JoranConfigurator configurator = new JoranConfigurator();
+            configurator.setContext(context);
+            configurator.doConfigure(logbackConfiguration);
+
+            // Dump any errors that occur during logback init
+            StatusPrinter.printInCaseOfErrorsOrWarnings(context);
+
+        }
+        catch (JoranException e) {
+            logger.error("Initialization of logback failed: {}", e.getMessage());
+            logger.debug("Unable to load logback configuration..", e);
+        }
+        
+    }
+
+}
+

guacamole/src/main/resources/logback.xml

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+   Copyright (C) 2014 Glyptodon LLC
+
+   Permission is hereby granted, free of charge, to any person obtaining a copy
+   of this software and associated documentation files (the "Software"), to deal
+   in the Software without restriction, including without limitation the rights
+   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+   copies of the Software, and to permit persons to whom the Software is
+   furnished to do so, subject to the following conditions:
+
+   The above copyright notice and this permission notice shall be included in
+   all copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+   THE SOFTWARE.
+-->
+<configuration>
+
+    <!-- Default appender -->
+    <appender name="GUAC-DEFAULT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <!-- Log at INFO level -->
+    <root level="info">
+        <appender-ref ref="GUAC-DEFAULT" />
+    </root>
+
+</configuration>

guacamole/src/main/webapp/WEB-INF/web.xml

@@ -37,6 +37,11 @@
         <listener-class>org.glyptodon.guacamole.net.basic.websocket.WebSocketSupportLoader</listener-class>
     </listener>
 
+    <!-- Init logging on startup -->
+    <listener>
+        <listener-class>org.glyptodon.guacamole.net.basic.log.LogbackInitializer</listener-class>
+    </listener>
+
     <!-- Authenticate against service calls and pages -->
     <filter>
         <filter-name>AuthenticatingFilter</filter-name>