Allow configuration of DEBUG logging using Eclipse bundle tracing

org.eclipse.m2e.logback/META-INF/MANIFEST.MF

@@ -1,7 +1,7 @@
 Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-SymbolicName: org.eclipse.m2e.logback;singleton:=true
-Bundle-Version: 2.1.100.qualifier
+Bundle-Version: 2.1.101.qualifier
 Bundle-Name: M2E Logback Appender and Configuration
 Bundle-Vendor: Eclipse.org - m2e
 Bundle-RequiredExecutionEnvironment: JavaSE-17

org.eclipse.m2e.logback/defaultLogbackConfiguration/logback.xml

@@ -4,7 +4,7 @@
       <pattern>%date [%thread] %-5level %logger{35} - %msg%n</pattern>
     </encoder>
     <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
-      <level>OFF</level> <!-- change to DEBUG to mimic '-consolelog' behaviour -->
+      <level>${org.eclipse.m2e.log.console.threshold:-OFF}</level> <!-- change to DEBUG to mimic '-consolelog' behaviour -->
     </filter>
   </appender>
 
@@ -31,7 +31,7 @@
 
   <appender name="MavenConsoleLog" class="org.eclipse.m2e.logback.appender.MavenConsoleAppender">
   </appender>
-        
+
   <root level="INFO">
     <appender-ref ref="FILE" />
     <appender-ref ref="STDOUT" />

org.eclipse.m2e.logback/src/org/eclipse/m2e/logback/configuration/M2ELogbackConfigurator.java

@@ -19,6 +19,8 @@
 import java.nio.file.DirectoryStream;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.Map;
+import java.util.Map.Entry;
 import java.util.Properties;
 import java.util.SortedMap;
 import java.util.Timer;
@@ -27,14 +29,18 @@
 import java.util.function.BooleanSupplier;
 
 import org.osgi.framework.Bundle;
+import org.osgi.util.tracker.ServiceTracker;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import org.eclipse.core.runtime.ILog;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.Status;
+import org.eclipse.osgi.service.debug.DebugOptions;
+import org.eclipse.osgi.service.environment.EnvironmentInfo;
 
 import ch.qos.logback.classic.BasicConfigurator;
+import ch.qos.logback.classic.Level;
 import ch.qos.logback.classic.LoggerContext;
 import ch.qos.logback.classic.joran.JoranConfigurator;
 import ch.qos.logback.classic.spi.Configurator;
@@ -51,9 +57,12 @@ public class M2ELogbackConfigurator extends BasicConfigurator implements Configu
   // This has to match the log directory in defaultLogbackConfiguration/logback.xml
   private static final String PROPERTY_LOG_DIRECTORY = "org.eclipse.m2e.log.dir"; //$NON-NLS-1$
 
+  // This has to match the log directory in defaultLogbackConfiguration/logback.xml
+  private static final String PROPERTY_LOG_CONSOLE_THRESHOLD = "org.eclipse.m2e.log.console.threshold"; //$NON-NLS-1$
+
   @Override
   public void configure(LoggerContext lc) {
-    // Bug 337167: Configuring Logback requires the state-location. If not yet initialized it will be initialized to the default value, 
+    // Bug 337167: Configuring Logback requires the state-location. If not yet initialized it will be initialized to the default value,
     // but this prevents the workspace-chooser dialog to show up in a stand-alone Eclipse-product. Therefore we have to wait until the resources plug-in has started.
     // This happens if a Plug-in that uses SLF4J is started before the workspace has been selected.
     if(!isStateLocationInitialized()) {
@@ -84,9 +93,14 @@ private synchronized void configureLogback(LoggerContext lc) {
       if(System.getProperty(PROPERTY_LOG_DIRECTORY, "").length() <= 0) { //$NON-NLS-1$
         System.setProperty(PROPERTY_LOG_DIRECTORY, stateDir.toAbsolutePath().toString());
       }
+      if(System.getProperty(PROPERTY_LOG_CONSOLE_THRESHOLD, "").length() <= 0) { //$NON-NLS-1$
+        if(isConsoleLogEnable()) {
+          System.setProperty(PROPERTY_LOG_CONSOLE_THRESHOLD, Level.DEBUG.levelStr);
+        }
+      }
       loadConfiguration(lc, configFile.toUri().toURL());
 
-      //Delete old logs in legacy logback plug-in's state location. Can sum up to 1GB of disk-space. 
+      //Delete old logs in legacy logback plug-in's state location. Can sum up to 1GB of disk-space.
       // TODO: can be removed when some time has passed and it is unlikely old workspaces that need clean-up are used.
       Path legacyLogbackState = stateDir.resolveSibling("org.eclipse.m2e.logback.configuration");
       if(Files.isDirectory(legacyLogbackState)) {
@@ -100,7 +114,17 @@ private synchronized void configureLogback(LoggerContext lc) {
         Files.delete(legacyLogbackState);
       }
     } catch(Exception e) {
-      LOG.log(Status.warning("Exception while setting up logging:" + e.getMessage(), e)); //$NON-NLS-1$
+      LOG.log(Status.warning("Exception while setting up logging:" + e.getMessage(), e));
+    }
+  }
+
+  private boolean isConsoleLogEnable() {
+    ServiceTracker<EnvironmentInfo, Object> tracker = openServiceTracker(EnvironmentInfo.class);
+    try {
+      EnvironmentInfo environmentInfo = (EnvironmentInfo) tracker.getService();
+      return environmentInfo != null && "true".equals(environmentInfo.getProperty("eclipse.consoleLog")); //$NON-NLS-1$
+    } finally {
+      tracker.close();
     }
   }
 
@@ -113,9 +137,37 @@ private static void loadConfiguration(LoggerContext lc, URL configFile) throws J
 
     StatusPrinter.printInCaseOfErrorsOrWarnings(lc);
 
+    applyDebugLogLevels(lc);
+
     logJavaProperties(LoggerFactory.getLogger(M2ELogbackConfigurator.class));
   }
 
+  private static void applyDebugLogLevels(LoggerContext lc) {
+    ServiceTracker<DebugOptions, Object> tracker = openServiceTracker(DebugOptions.class);
+    try {
+      DebugOptions debugOptions = (DebugOptions) tracker.getService();
+      if(debugOptions != null) {
+        Map<String, String> options = debugOptions.getOptions();
+        for(Entry<String, String> entry : options.entrySet()) {
+          String key = entry.getKey();
+          String value = entry.getValue();
+          if(key.endsWith("/debugLog") && "true".equals(value)) {
+            lc.getLogger(key.replace("/debugLog", "")).setLevel(Level.DEBUG);
+          }
+        }
+      }
+    } finally {
+      tracker.close();
+    }
+  }
+
+  private static <T> ServiceTracker<T, Object> openServiceTracker(Class<T> serviceClass) {
+    Bundle bundle = Platform.getBundle("org.eclipse.m2e.core"); // fragments don't have a BundleContext
+    ServiceTracker<T, Object> tracker = new ServiceTracker<>(bundle.getBundleContext(), serviceClass, null);
+    tracker.open();
+    return tracker;
+  }
+
   // --- utility methods ---
 
   private static boolean isStateLocationInitialized() {