Added logLevelFilter

lib/log4js-node.js

@@ -184,6 +184,10 @@ var appenderMakers = {
       layout = layoutMakers[config.layout.type](config.layout);
     }
     return consoleAppender(layout);
+  },
+  "logLevelFilter": function(config) {
+    var appender = appenderMakers[config.appender.type](config.appender);
+    return logLevelFilter(config.level, appender);
   }
 };
 
@@ -196,15 +200,20 @@ var layoutMakers = {
   }
 };
 
+function configureAppender(appenderConfig) {
+}
+
 function configureAppenders(appenderList) {
   log4js.clearAppenders();
   if (appenderList) {
-    appenderList.forEach(
+    appenderList.forEach(function(appenderConfig) {
-      function(appenderConfig) {
       var appender = appenderMakers[appenderConfig.type](appenderConfig);
+      if (appender) {
         log4js.addAppender(appender, appenderConfig.category);    
+      } else {
+        throw new Error("log4js configuration problem for "+sys.inspect(appenderConfig));
       }
-    );
+    });
   } else {
     log4js.addAppender(consoleAppender);
   }
@@ -263,6 +272,10 @@ Level.prototype.isLessThanOrEqualTo = function(otherLevel) {
   return this.level <= otherLevel.level;
 };
 
+Level.prototype.isGreaterThanOrEqualTo = function(otherLevel) {
+    return this.level >= otherLevel.level;
+};
+
 /**
  * Models a logging event.
  * @constructor
@@ -369,15 +382,9 @@ consoleAppender = function (layout) {
 fileAppender = function(file, layout) {
 	layout = layout || basicLayout;	
 	file = file || "log4js.log";	
-  var logFile;
   //waits are generally bad, but we need 
   //the file to be open before we start doing any writing.
-  posix
+  var logFile = posix.open(file, process.O_APPEND | process.O_WRONLY | process.O_CREAT, 0644).wait();    
-    .open(file, process.O_APPEND | process.O_WRONLY | process.O_CREAT, 0644)
-    .addCallback(function(fileDescriptor) { logFile = fileDescriptor; })
-    .addErrback(function(err) { throw new Error("Could not open logfile "+file+", error was: "+sys.inspect(err)); })
-    .wait();
-    
   //register ourselves as listeners for shutdown
   //so that we can close the file.
   //not entirely sure this is necessary, but still.
@@ -388,6 +395,15 @@ fileAppender = function(file, layout) {
   };
 };
 
+logLevelFilter = function(levelString, appender) {
+  var level = Level.toLevel(levelString);
+  return function(logEvent) {
+    if (logEvent.level.isGreaterThanOrEqualTo(level)) {
+      appender(logEvent);
+    }
+  }
+};
+
 /**
  * BasicLayout is a simple layout for storing the logs. The logs are stored
  * in following format:
@@ -596,6 +612,7 @@ Date.prototype.toFormattedString = function(format) {
 
 log4js.consoleAppender = consoleAppender;
 log4js.fileAppender = fileAppender;
+log4js.logLevelFilter = logLevelFilter;
 log4js.basicLayout = basicLayout;
 log4js.patternLayout = patternLayout;
 log4js.messagePassThroughLayout = messagePassThroughLayout;

spec/fixtures/with-logLevelFilter.json

@@ -0,0 +1,28 @@
+{
+  appenders: [
+    { 
+      category: "tests", 
+      type: "logLevelFilter",
+      level: "WARN",
+      appender: {
+        type: "file",
+        filename: "tmp-tests-warnings.log", 
+        layout: { 
+          type: "messagePassThrough" 
+        } 
+      }
+    },
+    { 
+      category: "tests", 
+      type: "file",
+      filename: "tmp-tests.log", 
+      layout: { 
+        type: "messagePassThrough" 
+      } 
+    }
+  ],
+  
+  levels: {
+    "tests":  "DEBUG"
+  }
+}

spec/spec.logging.js

@@ -1,19 +1,18 @@
 posix = require('posix');
 
-waitForWriteAndThenRead = function(filename) {
+waitForWriteAndThenRead = function (filename) {
   //here's the tricky part - writes are asynchronous
   //so I'm going to make a promise, wait a bit and then
   //try to read the file.
   var content, promise = new process.Promise();
+  promise.addCallback(function() {
+    content = posix.cat(filename).timeout(500).wait();    
+  });
   setTimeout(function() {
     promise.emitSuccess();
-  }, 50);
+  }, 0);
-  promise.addCallback(function() {
-    posix.cat(filename).addCallback(
-      function(fileContents) { content = fileContents; }
-    ).wait();
-  }).wait();
   
+  promise.wait();
   return content;
 }
 
@@ -161,14 +160,40 @@ describe 'log4js'
     end
   end
   
+  describe 'logLevelFilter'
+  
+    it 'should only pass log events greater than or equal to its own level'
+      var logEvent;
+      log4js.addAppender(log4js.logLevelFilter('ERROR', function(evt) { logEvent = evt; }));
+      logger.debug('this should not trigger an event');
+      logEvent.should.be undefined
+      
+      logger.warn('neither should this');
+      logEvent.should.be undefined
+      
+      logger.error('this should, though');
+      logEvent.should.not.be undefined
+      logEvent.message.should.be 'this should, though'
+      
+      logger.fatal('so should this')
+      logEvent.message.should.be 'so should this'
+    end
+    
+  end
+  
   describe 'configure'    
-    before
+    before_each
       log4js.clearAppenders();
       try {
         posix.unlink('./tmp-tests.log').wait();
       } catch(e) {
         print('Could not delete tmp-tests.log: '+e.message);
       }
+      try {
+        posix.unlink('./tmp-tests-warnings.log').wait();
+      } catch (e) {
+        print('Could not delete tmp-tests-warnings.log: '+e.message);
+      }
     end
 
     it 'should load appender configuration from a json file'
@@ -184,6 +209,19 @@ describe 'log4js'
       event.message.should.be 'this should fire an event'
       waitForWriteAndThenRead('./tmp-tests.log').should.be 'this should fire an event\n'
     end
+    
+    it 'should handle logLevelFilter configuration'
+      log4js.configure('spec/fixtures/with-logLevelFilter.json');
+      event = undefined;
+      
+      logger.info('main');
+      logger.error('both');
+      logger.warn('both');
+      logger.debug('main');
+
+      waitForWriteAndThenRead('./tmp-tests.log').should.be 'main\nboth\nboth\nmain\n'
+      waitForWriteAndThenRead('./tmp-tests-warnings.log').should.be 'both\nboth\n'
+    end
   end
 end