migrated logLevelFilter tests to mocha, changed filter api slightly

0.7-changes

@@ -10,4 +10,6 @@ appenders now only need to provide configure function
 log4js.configure now only takes single argument (no options)
 tests use mocha not vows
 replaced my debug lib with tjholowaychuk's debug (more of a standard)
-options.cwd removed - filenames should always be specified in full, not relative
+options.cwd removed - filenames should always be specified in full, not relative
+loglevelfilter changed to accept a list of log levels it allows
+appenders that wrap other appenders must reference them by name

lib/appenders/logLevelFilter.js

@@ -1,21 +1,40 @@
 "use strict";
 var levels = require('../levels')
+, debug = require('debug')('log4js:logLevelFilter')
 , log4js = require('../log4js');
 
-function logLevelFilter (levelString, appender) {
-  var level = levels.toLevel(levelString);
+function logLevelFilter(allowedLevels, appender) {
   return function(logEvent) {
-    if (logEvent.level.isGreaterThanOrEqualTo(level)) {
+    debug("Checking ", logEvent.level, " against ", allowedLevels);
+    if (allowedLevels.some(function(item) { return item.level === logEvent.level.level; })) {
+      debug("Sending ", logEvent, " to appender ", appender);
       appender(logEvent);
     }
   };
 }
 
-function configure(config) {
-  log4js.loadAppender(config.appender.type);
-  var appender = log4js.appenderMakers[config.appender.type](config.appender);
-  return logLevelFilter(config.level, appender);
+function configure(config, appenderByName) {
+  if (!Array.isArray(config.allow)) {
+    throw new Error("No allowed log levels specified.");
+  }
+
+  var allowedLevels = config.allow.map(function(allowed) {
+    var level = levels.toLevel(allowed);
+    if (!level) {
+      throw new Error("Unrecognised log level '" + allowed + "'.");
+    }
+    return level;
+  });
+
+  if (allowedLevels.length === 0) {
+    throw new Error("No allowed log levels specified.");
+  }
+
+  if (!config.appender) {
+    throw new Error("Missing an appender.");
+  }
+
+  return logLevelFilter(allowedLevels, appenderByName(config.appender));
 }
 
-exports.appender = logLevelFilter;
 exports.configure = configure;

lib/log4js.js

@@ -200,6 +200,14 @@ function clearAppenders () {
   appenders = {};
 }
 
+function appenderByName(name) {
+  if (appenders.hasOwnProperty(name)) {
+    return appenders[name];
+  } else {
+    throw new Error("Appender '" + name + "' not found.");
+  }
+}
+
 function configureAppenders(appenderMap) {
   clearAppenders();
   Object.keys(appenderMap).forEach(function(appenderName) {
@@ -207,7 +215,7 @@ function configureAppenders(appenderMap) {
       loadAppender(appenderConfig.type);
       appenderConfig.makers = appenderMakers;
       try {
-        appenders[appenderName] = appenderMakers[appenderConfig.type](appenderConfig);
+        appenders[appenderName] = appenderMakers[appenderConfig.type](appenderConfig, appenderByName);
       } catch(e) {
         throw new Error("log4js configuration problem for appender '" + appenderName + "'. Error was " + e.stack);
       }

test/logLevelFilter-test.js

@@ -1,16 +1,124 @@
 "use strict";
-var vows = require('vows')
-, fs = require('fs')
-, assert = require('assert');
+var should = require('should')
+, sandbox = require('sandboxed-module')
+, log4js = require('../lib/log4js');
 
-function remove(filename) {
-  try {
-    fs.unlinkSync(filename);
-  } catch (e) {
-    //doesn't really matter if it failed
-  }
-}
+describe('log level filter', function() {
+  describe('when configured correctly', function() {
+    var events = [], logger;
 
+    before(function() {
+      var log4js_sandboxed = sandbox.require(
+        '../lib/log4js',
+        { requires: 
+          { './appenders/console':
+            { configure: function() { return function(evt) { events.push(evt); }; } }
+          }
+        }
+      );
+      log4js_sandboxed.configure({
+        appenders: {
+          "console": { type: "console", layout: { type: "messagePassThrough" } },
+          "errors only": {
+            type: "logLevelFilter",
+            allow: [ "ERROR", "FATAL" ],
+            appender: "console"
+          }
+        },
+        categories: {
+          default: { level: "DEBUG", appenders: [ "errors only" ] }
+        }
+      });
+      logger = log4js_sandboxed.getLogger("test");        
+    });
+
+    it('should pass events to an appender if they match', function() {
+      logger.error("oh no");
+      logger.fatal("boom");
+
+      events.should.have.length(2);
+      events[0].data[0].should.eql("oh no");
+      events[1].data[0].should.eql("boom");
+    });
+
+    it('should not pass events to the appender if they do not match', function() {
+      events.should.have.length(2);
+      logger.debug("cheese");
+      events.should.have.length(2);
+      logger.info("yawn");
+      events.should.have.length(2);
+    });
+  });
+
+  it('should complain if it has no appender', function() {
+    (function() {
+      log4js.configure({
+        appenders: {
+          "errors": {
+            type: "logLevelFilter",
+            allow: [ "ERROR", "FATAL" ]
+          }
+        },
+        categories: {
+          default: { level: "DEBUG", appenders: [ "errors" ] }
+        }
+      });
+    }).should.throw(/Missing an appender\./);
+  });
+
+  it('should complain if it has no list of allowed levels', function() {
+    (function() {
+      log4js.configure({
+        appenders: {
+          "console": { type: "console" },
+          "errors": {
+            type: "logLevelFilter",
+            appender: "console"
+          }
+        },
+        categories: {
+          default: { level: "DEBUG", appenders: [ "errors" ] }
+        }
+      });
+    }).should.throw(/No allowed log levels specified\./);
+  });
+
+  it('should complain if the referenced appender does not exist', function() {
+    (function() {
+      log4js.configure({
+        appenders: {
+          "errors": {
+            type: "logLevelFilter",
+            allow: [ "ERROR" ],
+            appender: "console"
+          }
+        },
+        categories: {
+          default: { level: "DEBUG", appenders: [ "errors" ] }
+        }
+      });
+    }).should.throw(/Appender 'console' not found\./);
+  });
+
+  it('should complain if the list of levels is not valid', function() {
+    (function() {
+      log4js.configure({
+        appenders: {
+          "errors": {
+            type: "logLevelFilter",
+            allow: [ "cheese", "biscuits", "ERROR" ],
+            appender: { type: "console" }
+          }
+        },
+        categories: {
+          default: { level: "DEBUG", appenders: [ "errors" ] }
+        }
+      });
+    }).should.throw(/Unrecognised log level 'cheese'\./);
+  });
+});
+
+/*
 vows.describe('log4js logLevelFilter').addBatch({
   'appender': {
     topic: function() {
@@ -76,3 +184,4 @@ vows.describe('log4js logLevelFilter').addBatch({
     }
   }
 }).export(module);
+*/