Merge pull request log4js-node#70 from NetDevLtd/feature/configureNoL…

…evels

log4js.configure({}) resets all loggers' levels to TRACE

lib/log4js.js

@@ -201,7 +201,7 @@ function Logger (name, level) {
 util.inherits(Logger, events.EventEmitter);
 
 Logger.prototype.setLevel = function(level) {
-    this.level = levels.toLevel(level, levels.TRACE);
+    this.level = levels.toLevel(level, this.level || levels.TRACE);
 };
 
 Logger.prototype.removeLevel = function() {

test/test-configureNoLevels.js

@@ -0,0 +1,126 @@
+// This test shows unexpected behaviour for log4js.configure() in log4js-node@0.4.3 and earlier:
+// 1) log4js.configure(), log4js.configure(null), log4js.configure({}), log4js.configure(<some object with no levels prop>)
+// all set all loggers levels to trace, even if they were previously set to something else.
+// 2) log4js.configure({levels:{}}), log4js.configure({levels: {foo: bar}}) leaves previously set logger levels intact.
+//
+
+// Basic set up
+var vows = require('vows');
+var assert = require('assert');
+var toLevel = require('../lib/levels').toLevel;
+
+// uncomment one or other of the following to see progress (or not) while running the tests
+// var showProgress = console.log;
+var showProgress = function() {};
+
+
+// Define the array of levels as string to iterate over.
+var strLevels= ['Trace','Debug','Info','Warn','Error','Fatal'];
+
+// setup the configurations we want to test
+var configs = {
+  'nop': 'nop', // special case where the iterating vows generator will not call log4js.configure
+  'is undefined': undefined,
+  'is null': null,
+  'is empty': {},
+  'has no levels': {foo: 'bar'},
+  'has null levels': {levels: null},
+  'has empty levels': {levels: {}},
+  'has random levels': {levels: {foo: 'bar'}},
+  'has some valid levels': {levels: {A: 'INFO'}}
+}
+
+// Set up the basic vows batches for this test
+var batches = [];
+
+
+function getLoggerName(level) {
+  return level+'-logger';
+}
+
+// the common vows top-level context, whether log4js.configure is called or not
+// just making sure that the code is common,
+// so that there are no spurious errors in the tests themselves.
+function getTopLevelContext(nop, configToTest, name) {
+  return {
+    topic: function() {
+      var log4js = require('../lib/log4js');
+      // create loggers for each level,
+      // keeping the level in the logger's name for traceability
+      strLevels.forEach(function(l) {
+        log4js.getLogger(getLoggerName(l)).setLevel(l);
+      });
+
+      if (!nop) {
+        showProgress('** Configuring log4js with', configToTest);
+        log4js.configure(configToTest);
+      }
+      else {
+        showProgress('** Not configuring log4js');
+      }
+      return log4js;
+    }
+  }
+};
+
+showProgress('Populating batch object...');
+
+// Populating the batches programmatically,
+// as there are (configs.length x strLevels.length x strLevels.length) = 324 possible test combinations
+for (var cfg in configs) {
+  var configToTest = configs[cfg];
+  var nop = configToTest === 'nop';
+  var context;
+  if (nop) {
+    context = 'Setting up loggers with initial levels, then NOT setting a configuration,';
+  }
+  else {
+    context = 'Setting up loggers with initial levels, then setting a configuration which '+cfg+',';
+  }
+
+  showProgress('Setting up the vows batch and context for '+context);
+  // each config to be tested has its own vows batch with a single top-level context
+  var batch={};
+  batch[context]= getTopLevelContext(nop, configToTest, context);
+  batches.push(batch);
+
+  // each top-level context has strLevels sub-contexts, one per logger which has set to a specific level in the top-level context's topic
+  strLevels.forEach(function (baseLevel) {
+    var baseLevelSubContext = 'and checking the logger whose level was set to '+baseLevel ;
+    batch[context][baseLevelSubContext] = {topic: baseLevel};
+
+    // each logging level has strLevels sub-contexts,
+    // to exhaustively test all the combinations of setLevel(baseLevel) and isLevelEnabled(comparisonLevel) per config
+    strLevels.forEach(function (comparisonLevel) {
+      var comparisonLevelSubContext = 'with isLevelEnabled('+comparisonLevel+')';
+
+      // calculate this independently of log4js, but we'll add a vow later on to check that we're not mismatched with log4js
+      var expectedResult = strLevels.indexOf(baseLevel) <= strLevels.indexOf(comparisonLevel);
+
+      // the topic simply gathers all the parameters for the vow into an object, to simplify the vow's work.
+      batch[context][baseLevelSubContext][comparisonLevelSubContext] = {topic: function(baseLevel, log4js){
+        return {comparisonLevel: comparisonLevel, baseLevel: baseLevel, log4js: log4js, expectedResult: expectedResult};
+      }};
+
+      var vow = 'should return '+expectedResult;
+      batch[context][baseLevelSubContext][comparisonLevelSubContext][vow] = function(topic){
+        var result = topic.log4js.getLogger(getLoggerName(topic.baseLevel)).isLevelEnabled(topic.log4js.levels.toLevel(topic.comparisonLevel));
+        assert.equal(result, topic.expectedResult, 'Failed: '+getLoggerName(topic.baseLevel)+'.isLevelEnabled( '+topic.comparisonLevel+' ) returned '+result);
+      };
+
+      // the extra vow to check the comparison between baseLevel and comparisonLevel we performed earlier matches log4js' comparison too
+      batch[context][baseLevelSubContext][comparisonLevelSubContext]['finally checking for comparison mismatch with log4js'] = function(topic){
+        var er = topic.log4js.levels.toLevel(topic.baseLevel).isLessThanOrEqualTo(topic.log4js.levels.toLevel(topic.comparisonLevel));
+        assert.equal(er, topic.expectedResult, 'Mismatch: for setLevel('+topic.baseLevel+') was expecting a comparison with '+topic.comparisonLevel+' to be '+topic.expectedResult);
+      };
+    });
+  });
+};
+
+showProgress('Running tests');
+var v = vows.describe('log4js.configure(), with or without a "levels" property');
+
+batches.forEach(function(batch) {v=v.addBatch(batch)});
+
+v.export(module);
+