Angular study sheet

Difference between factory, service, and provider


See also.

An Angular factory can return any type (Function, Number, String.) Whatever is returned is what is used when the factory is injected. Hence, you can easily use a JavaScript constructor function, and instantiate new copies within controllers or other services.

var app = angular.module("TestApp", []);
app.factory("Cat", [function(){
  function Cat(name){ = name;
  Cat.prototype.noise = "meow!";
  return Cat;

With a service, you directly attach properties and methods to "this". It is as if the entire service were within a constructor function, which is returned with the new keyword when the service is injected.

app.service("CatService", [function(){ = "Unknown";
  this.noise = "meow!";

A provider is much like a factory, in that it can return any time. But unlike a factory, it can be configured in the config stage, before the app officially launches, given default values, etc.

app.provider("kitten", [function(){
  var defaultOwner = "Terrence";   //default owner of the kittens
  var defaultName = "Herbie";      //default name of all the kittens
  var defaultAge = 1;

  this.setDefaultOwner = function(newOwner){
    defaultOwner = newOwner;

  this.setDefaultName = function(newName){
    defaultName = newName;

  this.setDefaultAge = function(newAge){
    defaultAge = newAge;

  function Kitten(name, age, owner){, name, age, owner);    //call the superconstructor = name || defaultName;
    this.age = age || defaultAge;
    this.owner = owner || defaultOwner;

  this.$get = ["CatService", function(CatService){
    //Let's make Kitten inherit from Cat!
    Kitten.prototype = CatService;
    Kitten._super = CatService.constructor;         //now the Kitten constructor has a reference to the cat superconstructor

    return Kitten;