prepend operation

Author: djih

CHANGELOG.md

@@ -1,6 +1,7 @@
 ## Unreleased
 
 * Add support for passing callback function to identify.
+* Add support for prepend user property operation.
 
 ### 2.9.1 (March 6, 2016)
 

README.md

@@ -14,10 +14,10 @@ Amplitude-Javascript
           r.onload=function(){e.amplitude.runQueuedFunctions()};var i=t.getElementsByTagName("script")[0];
           i.parentNode.insertBefore(r,i);var s=function(){this._q=[];return this};function o(e){
           s.prototype[e]=function(){this._q.push([e].concat(Array.prototype.slice.call(arguments,0)));
-          return this}}var a=["add","append","clearAll","set","setOnce","unset"];for(var c=0;c<a.length;c++){
+          return this}}var a=["add","append","clearAll","prepend","set","setOnce","unset"];for(var c=0;c<a.length;c++){
           o(a[c])}n.Identify=s;var u=["init","logEvent","logRevenue","setUserId","setUserProperties","setOptOut","setVersionName","setDomain","setDeviceId","setGlobalUserProperties","identify","clearUserProperties"];
-          function l(e){function t(t){e[t]=function(){e._q.push([t].concat(Array.prototype.slice.call(arguments,0)));
-          }}for(var n=0;n<u.length;n++){t(u[n])}}l(n);e.amplitude=n})(window,document);
+          function p(e){function t(t){e[t]=function(){e._q.push([t].concat(Array.prototype.slice.call(arguments,0)));
+          }}for(var n=0;n<u.length;n++){t(u[n])}}p(n);e.amplitude=n})(window,document);
 
           amplitude.init("YOUR_API_KEY_HERE");
         </script>
@@ -120,6 +120,13 @@ The SDK supports the operations `set`, `setOnce`, `unset`, and `add` on individu
     amplitude.identify(identify);
     ```
 
+6. `prepend`: this will prepend a value or values to a user property. If the user property does not have a value set yet, it will be initialized to an empty list before the new values are prepended. If the user property has an existing value and it is not a list, it will be converted into a list with the new value prepended.
+
+    ```javascript
+    var identify = new amplitude.Identify().prepend('ab-tests', 'new-user-test').prepend('some_list', [1, 2, 3, 4, 'values']);
+    amplitude.identify(identify);
+    ```
+
 Note: if a user property is used in multiple operations on the same `Identify` object, only the first operation will be saved, and the rest will be ignored. In this example, only the set operation will be saved, and the add and unset will be ignored:
 
 ```javascript

amplitude-segment-snippet.min.js

@@ -1,6 +1,6 @@
 (function(e,t){var n=e.amplitude||{_q:[]};var r=function(){this._q=[];return this;
 };function i(e){r.prototype[e]=function(){this._q.push([e].concat(Array.prototype.slice.call(arguments,0)));
-return this}}var o=["add","append","clearAll","set","setOnce","unset"];for(var s=0;s<o.length;s++){
+return this}}var o=["add","append","clearAll","prepend","set","setOnce","unset"];for(var s=0;s<o.length;s++){
 i(o[s])}n.Identify=r;var a=["init","logEvent","logRevenue","setUserId","setUserProperties","setOptOut","setVersionName","setDomain","setDeviceId","setGlobalUserProperties","identify","clearUserProperties"];
 function c(e){function t(t){e[t]=function(){e._q.push([t].concat(Array.prototype.slice.call(arguments,0)));
 }}for(var n=0;n<a.length;n++){t(a[n])}}c(n);e.amplitude=n})(window,document);

amplitude-snippet.min.js

@@ -3,7 +3,7 @@ r.async=true;r.src="https://d24n15hnbwhuhn.cloudfront.net/libs/amplitude-2.9.1-m
 r.onload=function(){e.amplitude.runQueuedFunctions()};var i=t.getElementsByTagName("script")[0];
 i.parentNode.insertBefore(r,i);var s=function(){this._q=[];return this};function o(e){
 s.prototype[e]=function(){this._q.push([e].concat(Array.prototype.slice.call(arguments,0)));
-return this}}var a=["add","append","clearAll","set","setOnce","unset"];for(var c=0;c<a.length;c++){
+return this}}var a=["add","append","clearAll","prepend","set","setOnce","unset"];for(var c=0;c<a.length;c++){
 o(a[c])}n.Identify=s;var u=["init","logEvent","logRevenue","setUserId","setUserProperties","setOptOut","setVersionName","setDomain","setDeviceId","setGlobalUserProperties","identify","clearUserProperties"];
-function l(e){function t(t){e[t]=function(){e._q.push([t].concat(Array.prototype.slice.call(arguments,0)));
-}}for(var n=0;n<u.length;n++){t(u[n])}}l(n);e.amplitude=n})(window,document);
+function p(e){function t(t){e[t]=function(){e._q.push([t].concat(Array.prototype.slice.call(arguments,0)));
+}}for(var n=0;n<u.length;n++){t(u[n])}}p(n);e.amplitude=n})(window,document);

amplitude.js

@@ -2102,6 +2102,7 @@ var utils = require('./utils');
 var AMP_OP_ADD = '$add';
 var AMP_OP_APPEND = '$append';
 var AMP_OP_CLEAR_ALL = '$clearAll';
+var AMP_OP_PREPEND = '$prepend';
 var AMP_OP_SET = '$set';
 var AMP_OP_SET_ONCE = '$setOnce';
 var AMP_OP_UNSET = '$unset';
@@ -2139,6 +2140,11 @@ Identify.prototype.clearAll = function() {
   return this;
 };
 
+Identify.prototype.prepend = function(property, value) {
+  this._addOperation(AMP_OP_PREPEND, property, value);
+  return this;
+};
+
 Identify.prototype.set = function(property, value) {
   this._addOperation(AMP_OP_SET, property, value);
   return this;

amplitude.min.js

@@ -13,7 +13,7 @@
       this._q.push([fn].concat(Array.prototype.slice.call(arguments, 0))); return this;
     };
   }
-  var identifyFuncs = ['add', 'append', 'clearAll', 'set', 'setOnce', 'unset'];
+  var identifyFuncs = ['add', 'append', 'clearAll', 'prepend', 'set', 'setOnce', 'unset'];
   for (var i = 0; i < identifyFuncs.length; i++) {proxyIdentify(identifyFuncs[i]);}
   amplitude.Identify = Identify;
   var funcs = ['init', 'logEvent', 'logRevenue', 'setUserId', 'setUserProperties',

src/amplitude-snippet.js

@@ -10,6 +10,7 @@ var utils = require('./utils');
 var AMP_OP_ADD = '$add';
 var AMP_OP_APPEND = '$append';
 var AMP_OP_CLEAR_ALL = '$clearAll';
+var AMP_OP_PREPEND = '$prepend';
 var AMP_OP_SET = '$set';
 var AMP_OP_SET_ONCE = '$setOnce';
 var AMP_OP_UNSET = '$unset';
@@ -47,6 +48,11 @@ Identify.prototype.clearAll = function() {
   return this;
 };
 
+Identify.prototype.prepend = function(property, value) {
+  this._addOperation(AMP_OP_PREPEND, property, value);
+  return this;
+};
+
 Identify.prototype.set = function(property, value) {
   this._addOperation(AMP_OP_SET, property, value);
   return this;

src/identify.js

@@ -141,6 +141,41 @@ describe('Identify', function() {
     assert.deepEqual([property1, property2, property3, property4, property5], identify.properties);
   });
 
+    it ('should prepend properties', function () {
+    var property1 = 'var value';
+    var value1 = 'testValue';
+
+    var property2 = 'float value';
+    var value2 = 0.123;
+
+    var property3 = 'bool value';
+    var value3 = true;
+
+    var property4 = 'json value';
+    var value4 = {};
+
+    var property5 = 'list value';
+    var value5 = [1, 2, 'test'];
+
+    var identify = new Identify().prepend(property1, value1).prepend(property2, value2);
+    identify.prepend(property3, value3).prepend(property4, value4).prepend(property5, value5);
+
+    // identify should ignore this since duplicate key
+    identify.setOnce(property1, value3);
+
+    var expected = {
+      '$prepend': {}
+    }
+    expected['$prepend'][property1] = value1;
+    expected['$prepend'][property2] = value2;
+    expected['$prepend'][property3] = value3;
+    expected['$prepend'][property4] = value4;
+    expected['$prepend'][property5] = value5;
+
+    assert.deepEqual(expected, identify.userPropertiesOperations);
+    assert.deepEqual([property1, property2, property3, property4, property5], identify.properties);
+  });
+
   it ('should allow multiple operations', function () {
     var property1 = 'string value';
     var value1 = 'testValue';
@@ -156,15 +191,20 @@ describe('Identify', function() {
     var property5 = 'list value';
     var value5 = [1, 2, 'test'];
 
+    var property6 = 'int value';
+    var value6 = 100;
+
     var identify = new Identify().setOnce(property1, value1).add(property2, value2);
     identify.set(property3, value3).unset(property4).append(property5, value5);
+    identify.prepend(property6, value6);
 
     // identify should ignore this since duplicate key
     identify.set(property4, value3);
 
     var expected = {
       '$add': {},
       '$append': {},
+      '$prepend': {},
       '$set': {},
       '$setOnce': {},
       '$unset': {}
@@ -174,9 +214,10 @@ describe('Identify', function() {
     expected['$set'][property3] = value3;
     expected['$unset'][property4] = '-';
     expected['$append'][property5] = value5;
+    expected['$prepend'][property6] = value6;
 
     assert.deepEqual(expected, identify.userPropertiesOperations);
-    assert.deepEqual([property1, property2, property3, property4, property5], identify.properties);
+    assert.deepEqual([property1, property2, property3, property4, property5, property6], identify.properties);
   });
 
   it ('should disallow duplicate properties', function () {