add cookie storage as backup for local storage

djih · djih · commit 2ff5b8bb3e9f · 2015-10-22T19:44:56.000-07:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,5 +1,7 @@
 ## Unreleased
 
+* Migrate cookie data to local storage to address issue where having cookies disabled causes SDK to generate a new deviceId for returning users.
+
 ## 2.5.0 (September 30, 2015)
 
 * Add support for user properties operations (set, setOnce, add, unset).
diff --git a/amplitude.js b/amplitude.js
@@ -1888,7 +1888,7 @@ if (windowLocalStorageAvailable()) {
     div.load(attrKey);
     localStorage.length = div.XMLDocument.documentElement.attributes.length;
   } else {
-    /* Nothing we can do ... */
+    localStorage = require('./localstorage-cookie.js');
   }
 }
 if (!localStorage) {
@@ -1909,7 +1909,61 @@ if (!localStorage) {
 
 module.exports = localStorage;
 
-}, {}],
+}, {"./localstorage-cookie.js":20}],
+20: [function(require, module, exports) {
+/* jshint -W020, unused: false, noempty: false, boss: true */
+/* global escape, unescape */
+
+var Cookie = require('./cookie.js');
+
+var COOKIE_STORAGE_KEY = 'amplitude_storage';
+
+var cookieStorage = {
+  length: 0,
+
+  setItem: function(sKey, sValue) {
+    var store = Cookie.get(COOKIE_STORAGE_KEY) || {};
+
+    // don't add if cookie size exceeds 4k
+    var existingValue = '';
+    if (store.hasOwnProperty(sKey)) { existingValue = store[sKey]; }
+    var itemLength = escape(sKey).length + escape(sValue).length - escape(existingValue).length;
+    if (document.cookie.length + itemLength > 4*1024) { return; }
+
+    if (!store.hasOwnProperty(sKey)) { this.length++; }
+    store[sKey] = sValue;
+    Cookie.set(COOKIE_STORAGE_KEY, store);
+  },
+
+  getItem: function(sKey) {
+    var store = Cookie.get(COOKIE_STORAGE_KEY);
+    return store && store.hasOwnProperty(sKey) && store[sKey] || null;
+  },
+
+  removeItem: function(sKey) {
+    var store = Cookie.get(COOKIE_STORAGE_KEY);
+    if (!store || !store.hasOwnProperty(sKey)) { return; }
+    delete store[sKey];
+    Cookie.set(COOKIE_STORAGE_KEY, store);
+    this.length--;
+  },
+
+  clear: function() {
+    Cookie.set(COOKIE_STORAGE_KEY, {});
+    this.length = 0;
+  },
+
+  key: function(n) {
+    var store = Cookie.get(COOKIE_STORAGE_KEY);
+    if (!store) { return null; }
+    var keys = Object.keys(store);
+    return n < keys.length && keys[n] || null;
+  }
+};
+
+module.exports = cookieStorage;
+
+}, {"./cookie.js":3}],
 7: [function(require, module, exports) {
 /*
  * JavaScript MD5 1.0.1
@@ -2320,8 +2374,8 @@ Request.prototype.send = function(callback) {
 
 module.exports = Request;
 
-}, {"querystring":20}],
-20: [function(require, module, exports) {
+}, {"querystring":21}],
+21: [function(require, module, exports) {
 
 /**
  * Module dependencies.
@@ -2396,8 +2450,8 @@ exports.stringify = function(obj){
   return pairs.join('&');
 };
 
-}, {"trim":21,"type":22}],
-21: [function(require, module, exports) {
+}, {"trim":22,"type":23}],
+22: [function(require, module, exports) {
 
 exports = module.exports = trim;
 
@@ -2417,7 +2471,7 @@ exports.right = function(str){
 };
 
 }, {}],
-22: [function(require, module, exports) {
+23: [function(require, module, exports) {
 /**
  * toString ref.
  */
diff --git a/amplitude.min.js b/amplitude.min.js
diff --git a/src/localstorage-cookie.js b/src/localstorage-cookie.js
@@ -0,0 +1,51 @@
+/* jshint -W020, unused: false, noempty: false, boss: true */
+/* global escape, unescape */
+
+var Cookie = require('./cookie.js');
+
+var COOKIE_STORAGE_KEY = 'amplitude_storage';
+
+var cookieStorage = {
+  length: 0,
+
+  setItem: function(sKey, sValue) {
+    var store = Cookie.get(COOKIE_STORAGE_KEY) || {};
+
+    // don't add if cookie size exceeds 4k
+    var existingValue = '';
+    if (store.hasOwnProperty(sKey)) { existingValue = store[sKey]; }
+    var itemLength = escape(sKey).length + escape(sValue).length - escape(existingValue).length;
+    if (document.cookie.length + itemLength > 4*1024) { return; }
+
+    if (!store.hasOwnProperty(sKey)) { this.length++; }
+    store[sKey] = sValue;
+    Cookie.set(COOKIE_STORAGE_KEY, store);
+  },
+
+  getItem: function(sKey) {
+    var store = Cookie.get(COOKIE_STORAGE_KEY);
+    return store && store.hasOwnProperty(sKey) && store[sKey] || null;
+  },
+
+  removeItem: function(sKey) {
+    var store = Cookie.get(COOKIE_STORAGE_KEY);
+    if (!store || !store.hasOwnProperty(sKey)) { return; }
+    delete store[sKey];
+    Cookie.set(COOKIE_STORAGE_KEY, store);
+    this.length--;
+  },
+
+  clear: function() {
+    Cookie.set(COOKIE_STORAGE_KEY, {});
+    this.length = 0;
+  },
+
+  key: function(n) {
+    var store = Cookie.get(COOKIE_STORAGE_KEY);
+    if (!store) { return null; }
+    var keys = Object.keys(store);
+    return n < keys.length && keys[n] || null;
+  }
+};
+
+module.exports = cookieStorage;
diff --git a/src/localstorage.js b/src/localstorage.js
@@ -79,7 +79,7 @@ if (windowLocalStorageAvailable()) {
     div.load(attrKey);
     localStorage.length = div.XMLDocument.documentElement.attributes.length;
   } else {
-    /* Nothing we can do ... */
+    localStorage = require('./localstorage-cookie.js');
   }
 }
 if (!localStorage) {
diff --git a/test/localstorage.js b/test/localstorage.js
@@ -1,7 +1,7 @@
 describe('Localstorage', function() {
   var Amplitude = require('../src/amplitude.js');
   var localStorage = require('../src/localstorage.js');
-  // var cookieStorage = require('../src/localstorage-cookie.js');
+  var cookieStorage = require('../src/localstorage-cookie.js');
   var Cookie = require('../src/cookie.js');
 
   var apiKey = '000000';
@@ -38,6 +38,61 @@ describe('Localstorage', function() {
   afterEach(function() {
   });
 
+  describe('cookie storage', function() {
+
+    beforeEach(function() {
+      cookieStorage.clear();
+      assert.lengthOf(cookieStorage, 0);
+    });
+
+    it('should store values', function() {
+      cookieStorage.setItem('key-a', 'value-a');
+      assert.equal(cookieStorage.getItem('key-a'), 'value-a');
+      assert.lengthOf(cookieStorage, 1);
+    });
+
+    it('should return null for unstored keys', function() {
+      assert.isNull(cookieStorage.getItem('bogus_key'));
+      cookieStorage.setItem('key-a', 'value-a');
+      assert.isNull(cookieStorage.getItem('bogus_key'));
+    });
+
+    it('should remove values', function() {
+      cookieStorage.setItem('key-a', 'value-a');
+      assert.equal(cookieStorage.getItem('key-a'), 'value-a');
+      assert.lengthOf(cookieStorage, 1);
+      cookieStorage.removeItem('bogus_key');
+      assert.lengthOf(cookieStorage, 1);
+      cookieStorage.removeItem('key-a');
+      assert.isNull(cookieStorage.getItem('key-a'));
+      assert.lengthOf(cookieStorage, 0);
+    });
+
+    it('should replace values', function() {
+      cookieStorage.setItem('key-a', 'value-a');
+      assert.equal(cookieStorage.getItem('key-a'), 'value-a');
+      assert.lengthOf(cookieStorage, 1);
+      cookieStorage.setItem('key-a', 'value-b');
+      assert.equal(cookieStorage.getItem('key-a'), 'value-b');
+      assert.lengthOf(cookieStorage, 1);
+    });
+
+    it('should store values with entities', function() {
+      cookieStorage.setItem('key-a', 'this&that;with=an?<>');
+      assert.equal(cookieStorage.getItem('key-a'), 'this&that;with=an?<>');
+    });
+
+    it('should not store more than 4k', function() {
+      var longString = new Array(3*1024).join('a');
+
+      cookieStorage.setItem('key-a', longString);
+      cookieStorage.setItem('key-b', longString);
+
+      assert.equal(cookieStorage.getItem('key-a'), longString);
+      assert.isNull(cookieStorage.getItem('key-b'));
+    });
+  });
+
   describe('upgrade', function() {
 
     it('should migrate cookie values to localstorage', function() {

Original file line number	Diff line number	Diff line change
`@@ -79,7 +79,7 @@ if (windowLocalStorageAvailable()) {`
`79`	`79`	`div.load(attrKey);`
`80`	`80`	`localStorage.length = div.XMLDocument.documentElement.attributes.length;`
`81`	`81`	`} else {`
`82`		`- /* Nothing we can do ... */`
	`82`	`+ localStorage = require('./localstorage-cookie.js');`
`83`	`83`	`}`
`84`	`84`	`}`
`85`	`85`	`if (!localStorage) {`