How do I retrieve data using an AngularJS factory?

I am having a problem displaying product information from the database using an AngularJS factory. Basically its a shopping cart application that I modified to display the products from the database instead of a hard coded array.

Heres the main application file source code (app.js) :

'use strict';

var shop = angular.module('shop', []);

// create a data service that provides a store and a shopping cart that
// will be shared by all views (instead of creating fresh ones for each view)
shop.factory("DataService",['$http', function($http) {
    // create store
    var myStore = new store($http);

    // return data object with store and cart
    return {
       store: myStore
       //cart: myCart ignore for now
    }
}]);

// adding the config on the module
shop.config(function($routeProvider) {
      $routeProvider // angular object, injected dynamically
        .when('/', // we show the store on the root
          {
            controller: 'StoreController',
            templateUrl: 'partials/store.htm'
          })
        .when('/cart',
          {
            controller: 'CartController',
            templateUrl: 'partials/cart.htm'
          })
        .when('/checkout',
          {
            controller: 'CheckoutController',
            templateUrl: 'partials/checkout.htm'
          })
       .when('/invoice',
          {
            controller: 'InvoiceController',
            templateUrl: 'partials/invoice.htm'
          })
       .otherwise({ redirectTo: '/' }); // store
    });

var controllers = {};
controllers.StoreController = function($scope, $routeParams, DataService) {
  $scope.store = DataService.store;
  console.log($scope.store);
  //$scope.cart = DataService.cart;
}

The store source code (store.js) where I retrieve the data :

function store($http) {
  this.products = [];
  this.url = 'php/db.php';
  this.fields = [
    'product_id',
    'product_name', 
    'product_description', 
    'product_price'
  ];
  this.products = this.getProducts($http);
}

store.prototype.getProducts = function($http) {
  $http.post(this.url, { "action" : 'products', "fields" : this.fields })
    .success(function(data, status) {
      //$scope.result = data; // Show result from server in our <pre></pre> element
      //return data;
      this.products = data;
    })
    .error(function(data, status) {
      //return data || "Request failed";
      //this.status = status;        
      this.products = [];
  }); 
}

store.prototype.getProduct = function (sku) {
  for (var i = 0; i < this.products.length; i++) {
    if (this.products[i].sku == sku)
      return this.products[i];
  }
  return null;
}

Can anybody tell me what am I doing wrong here?

• Why cant I set my this.product variable to the database result?
• I would also like to extend the products class with more functions to save items to the database, how would I go about doing that?

Any advice much appreciated.

Regards

UPDATE

I have added the app.js code below, I am having an issue with the controller (StoreController) when accessing the data from the store class (store.js). It still shows an empty array. I have changed my code as suggested by m.e.conroy.

app.js

'use strict';

var shop = angular.module('shop', []);


shop.factory("DataService",['$http', '$q', function($http, $q) {
    // create store
    var myStore = new store($http, $q);
    return {
       store: myStore      
    }
}]);


// adding the config on the module
shop.config(function($routeProvider) {
      $routeProvider // angular object, injected dynamically
        .when('/', // we show the store on the root
          {
            controller: 'StoreController',
            templateUrl: 'partials/store.htm'
          })
        .when('/cart',
          {
            controller: 'CartController',
            templateUrl: 'partials/cart.htm'
          })
        .when('/checkout',
          {
            controller: 'CheckoutController',
            templateUrl: 'partials/checkout.htm'
          })
       .when('/invoice',
          {
            controller: 'InvoiceController',
            templateUrl: 'partials/invoice.htm'
          })
       .otherwise({ redirectTo: '/' }); // store
    });

var controllers = {};
controllers.StoreController = function($scope, $http, $routeParams, DataService) {
  $scope.store = DataService.store;              
}

shop.controller(controllers);