Merge pull request #117 from andrerod/dev

Improve RoleEnvironment eventEmitter

lib/serviceruntime/roleenvironment.js

@@ -40,7 +40,9 @@ var currentGoalState = null;
 var currentEnvironmentData = null;
 var lastState = null;
 var maxDateTime = new Date('9999-12-31T23:59:59.9999999');
-var eventEmitter = new events.EventEmitter();
+
+// Merge event emitter properties into the RoleEnvironment (export) object.
+RoleEnvironment = azureutil.merge(RoleEnvironment, new events.EventEmitter());
 
 /**
 * Returns a RoleInstance object that represents the role instance
@@ -246,11 +248,6 @@ RoleEnvironment.clearStatus = function (callback) {
   });
 };
 
-// TODO: find a better way to hook eventing up
-RoleEnvironment.on = function (event, callback) {
-  eventEmitter.on(event, callback);
-};
-
 RoleEnvironment._initialize = function (callback) {
   var getCurrentGoalState = function (finalCallback) {
     RoleEnvironment.runtimeClient.getCurrentGoalState(function (error, goalState) {
@@ -289,9 +286,9 @@ RoleEnvironment._initialize = function (callback) {
       } else {
         RoleEnvironment.runtimeClient = rtClient;
 
-        getCurrentGoalState(function (error) {
-          if (error) {
-            callback(error);
+        getCurrentGoalState(function (errorGetCurrentGoalState) {
+          if (errorGetCurrentGoalState) {
+            callback(errorGetCurrentGoalState);
           } else {
             if (RoleEnvironment.runtimeClient.listeners(ServiceRuntimeConstants.CHANGED).length === 0) {
               RoleEnvironment.runtimeClient.on(ServiceRuntimeConstants.CHANGED, function (newGoalState) {
@@ -336,7 +333,7 @@ RoleEnvironment._processGoalStateChange = function (newGoalState, callback) {
       if (changes.length === 0) {
         RoleEnvironment._acceptLatestIncarnation(newGoalState, last);
       } else {
-        eventEmitter.emit(ServiceRuntimeConstants.CHANGING, changes);
+        RoleEnvironment.emit(ServiceRuntimeConstants.CHANGING, changes);
 
         RoleEnvironment._acceptLatestIncarnation(newGoalState, last);
 
@@ -346,7 +343,7 @@ RoleEnvironment._processGoalStateChange = function (newGoalState, callback) {
           } else {
             currentEnvironmentData = environmentData;
 
-            eventEmitter.emit(ServiceRuntimeConstants.CHANGED, changes);
+            RoleEnvironment.emit(ServiceRuntimeConstants.CHANGED, changes);
             callback();
           }
         });
@@ -506,5 +503,5 @@ RoleEnvironment._calculateChanges = function (callback) {
 };
 
 RoleEnvironment._raiseStoppingEvent = function () {
-  eventEmitter.emit(ServiceRuntimeConstants.STOPPING);
+  RoleEnvironment.emit(ServiceRuntimeConstants.STOPPING);
 };

lib/util/util.js

@@ -195,4 +195,28 @@ exports.stringIsDate = function(date) {
   }
 
   return !isNaN(date.getTime());
-};
+};
+
+/**
+* Merges multiple objects.
+*
+* @param {object} object The objects to be merged
+* @return {object} The merged object.
+*/
+exports.merge = function () {
+  var source, sourceValue;
+  var target = arguments[0] || {};
+  var length = arguments.length;
+
+  for (var i = 1; i < length; i++) {
+    if ((source = arguments[i]) != null) {
+      for (var property in source) {
+        sourceValue = source[property];
+        if (sourceValue !== undefined) {
+          target[property] = sourceValue;
+        }
+      }
+    }
+  }
+  return target;
+}

test/serviceruntime/roleenvironment-tests.js

@@ -62,6 +62,22 @@ suite('roleenvironment-tests', function () {
     done();
   });
 
+  test('eventEmitter', function (done) {
+    // No event listeners registered yet
+    assert.equal(azure.RoleEnvironment.listeners(ServiceRuntimeConstants.CHANGED).length, 0);
+
+    // Register one event listener
+    var listener = function () { };
+    azure.RoleEnvironment.on(ServiceRuntimeConstants.CHANGED, listener);
+    assert.equal(azure.RoleEnvironment.listeners(ServiceRuntimeConstants.CHANGED).length, 1);
+
+    // Remove the event listener
+    azure.RoleEnvironment.removeListener(ServiceRuntimeConstants.CHANGED, listener);
+    assert.equal(azure.RoleEnvironment.listeners(ServiceRuntimeConstants.CHANGED).length, 0);
+
+    done();
+  });
+
   test('IsAvailable', function (done) {
     azure.RoleEnvironment.isAvailable(function (error1, isAvailable1) {
       assert.notEqual(error1, null);
@@ -163,7 +179,6 @@ suite('roleenvironment-tests', function () {
       }
     };
 
-    var originalFileInputChannelReadData = runtimeKernel.fileInputChannel._readData;
     runtimeKernel.fileInputChannel._readData = function (name, callback) {
       if (name === 'C:\\file.xml') {
         callback(undefined,
@@ -609,7 +624,7 @@ suite('roleenvironment-tests', function () {
     });
 
     // Make sure incarnation 1 is read
-    azure.RoleEnvironment.getConfigurationSettings(function (error, configurationSettings) {
+    azure.RoleEnvironment.getConfigurationSettings(function (error) {
       // Update to incarnation 2
       goalStateXml = "<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
         "<GoalState xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"" +
@@ -735,7 +750,7 @@ suite('roleenvironment-tests', function () {
     });
 
     // Make sure incarnation 1 is read
-    azure.RoleEnvironment.getConfigurationSettings(function (error, configurationSettings) {
+    azure.RoleEnvironment.getConfigurationSettings(function (error) {
       // Update to incarnation 2
       goalStateXml = "<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
         "<GoalState xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"" +