merging from master

Author: djih

CHANGELOG.md

@@ -1,6 +1,8 @@
 ## Unreleased
 
 * Add support for user properties operations (set, setOnce, add, unset).
+* Add support for passing callback function to init.
+* Fix bug to check that Window localStorage is available for use.
 
 ## 2.4.0 (September 4, 2015)
 

README.md

@@ -176,4 +176,8 @@ The status and response from the server are passed to the callback function, whi
   };
 ```
 
+You can also pass a callback function to init, which will get called after the SDK finishes its asynchronous loading. Note: no values are passed to the init callback function:
+
+    amplitude.init("YOUR_API_KEY_HERE", "USER_ID_HERE", null, callback_function);
+
 In the case that `optOut` is true, then no event will be logged, but the callback will be called. In the case that `batchEvents` is true, if the batch requirements `eventUploadThreshold` and `eventUploadPeriodMillis` are not met when `logEvent` is called, then no request is sent, but the callback is still called. In these cases, the callback will be called with an input status of 0 and response 'No request sent'.

amplitude.js

@@ -184,7 +184,7 @@ Amplitude.prototype.Identify = Identify;
  *   - includeUtm (boolean) Whether to send utm parameters with events. Defaults to false.
  *   - includeReferrer (boolean) Whether to send referrer info with events. Defaults to false.
  */
-Amplitude.prototype.init = function(apiKey, opt_userId, opt_config) {
+Amplitude.prototype.init = function(apiKey, opt_userId, opt_config, callback) {
   try {
     this.options.apiKey = apiKey;
     if (opt_config) {
@@ -255,6 +255,10 @@ Amplitude.prototype.init = function(apiKey, opt_userId, opt_config) {
   } catch (e) {
     log(e);
   }
+
+  if (callback && typeof(callback) === 'function') {
+    callback();
+  }
 };
 
 Amplitude.prototype._loadSavedUnsentEvents = function(unsentKey, queue) {
@@ -1690,7 +1694,22 @@ module.exports = {
  */
 var localStorage; // jshint ignore:line
 
-if (window.localStorage) {
+// test that Window.localStorage is available and works
+function windowLocalStorageAvailable() {
+  var uid = new Date();
+  var result;
+  try {
+    window.localStorage.setItem(uid, uid);
+    result = window.localStorage.getItem(uid) === String(uid);
+    window.localStorage.removeItem(uid);
+    return result;
+  } catch (e) {
+    // localStorage not available
+  }
+  return false;
+}
+
+if (windowLocalStorageAvailable()) {
   localStorage = window.localStorage;
 } else if (window.globalStorage) {
   // Firefox 2-3 use globalStorage

amplitude.min.js

@@ -72,7 +72,7 @@ Amplitude.prototype.Identify = Identify;
  *   - includeUtm (boolean) Whether to send utm parameters with events. Defaults to false.
  *   - includeReferrer (boolean) Whether to send referrer info with events. Defaults to false.
  */
-Amplitude.prototype.init = function(apiKey, opt_userId, opt_config) {
+Amplitude.prototype.init = function(apiKey, opt_userId, opt_config, callback) {
   try {
     this.options.apiKey = apiKey;
     if (opt_config) {
@@ -143,6 +143,10 @@ Amplitude.prototype.init = function(apiKey, opt_userId, opt_config) {
   } catch (e) {
     log(e);
   }
+
+  if (callback && typeof(callback) === 'function') {
+    callback();
+  }
 };
 
 Amplitude.prototype._loadSavedUnsentEvents = function(unsentKey, queue) {

src/amplitude.js

@@ -5,7 +5,22 @@
  */
 var localStorage; // jshint ignore:line
 
-if (window.localStorage) {
+// test that Window.localStorage is available and works
+function windowLocalStorageAvailable() {
+  var uid = new Date();
+  var result;
+  try {
+    window.localStorage.setItem(uid, uid);
+    result = window.localStorage.getItem(uid) === String(uid);
+    window.localStorage.removeItem(uid);
+    return result;
+  } catch (e) {
+    // localStorage not available
+  }
+  return false;
+}
+
+if (windowLocalStorageAvailable()) {
   localStorage = window.localStorage;
 } else if (window.globalStorage) {
   // Firefox 2-3 use globalStorage

src/localstorage.js

@@ -61,6 +61,19 @@ describe('Amplitude', function() {
       amplitude.init(apiKey, userId, {language: 'en-GB'});
       assert.propertyVal(amplitude.options, 'language', 'en-GB');
     });
+
+    it ('should not run callback if invalid callback', function() {
+      amplitude.init(apiKey, userId, null, 'invalid callback');
+    });
+
+    it ('should run valid callbacks', function() {
+      var counter = 0;
+      var callback = function() {
+        counter++;
+      };
+      amplitude.init(apiKey, userId, null, callback);
+      assert.equal(counter, 1);
+    });
   });
 
   describe('setUserProperties', function() {