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Methods

• provider(name, provider);

  Register a provider function with the $injector. Provider functions are constructor functions, whose instances are responsible for "providing" a factory for a service.

  Service provider names start with the name of the service they provide followed by Provider. For example, the $log service has a provider called $logProvider.

  Service provider objects can have additional methods which allow configuration of the provider and its service. Importantly, you can configure what kind of service is created by the $get method, or how that service will act. For example, the $logProvider has a method debugEnabled which lets you specify whether the $log service will log debug messages to the console or not.

  Parameters

  Param	Type	Details
  name	string	The name of the instance. NOTE: the provider will be available under name + 'Provider' key.
  provider	Objectfunction()	If the provider is: Object: then it should have a $get method. The $get method will be invoked using $injector.invoke() when an instance needs to be created. Constructor: a new instance of the provider will be created using $injector.instantiate(), then treated as object.

  Returns

  Object

  registered provider instance

  Examples

  The following example shows how to create a simple event tracking service and register it using $provide.provider().

  // Define the eventTracker provider
  function EventTrackerProvider() {
    var trackingUrl = '/track';
  
    // A provider method for configuring where the tracked events should been saved
    this.setTrackingUrl = function(url) {
      trackingUrl = url;
    };
  
    // The service factory function
    this.$get = ['$http', function($http) {
      var trackedEvents = {};
      return {
        // Call this to track an event
        event: function(event) {
          var count = trackedEvents[event] || 0;
          count += 1;
          trackedEvents[event] = count;
          return count;
        },
        // Call this to save the tracked events to the trackingUrl
        save: function() {
          $http.post(trackingUrl, trackedEvents);
        }
      };
    }];
  }
  
  describe('eventTracker', function() {
    var postSpy;
  
    beforeEach(module(function($provide) {
      // Register the eventTracker provider
      $provide.provider('eventTracker', EventTrackerProvider);
    }));
  
    beforeEach(module(function(eventTrackerProvider) {
      // Configure eventTracker provider
      eventTrackerProvider.setTrackingUrl('/custom-track');
    }));
  
    it('tracks events', inject(function(eventTracker) {
      expect(eventTracker.event('login')).toEqual(1);
      expect(eventTracker.event('login')).toEqual(2);
    }));
  
    it('saves to the tracking url', inject(function(eventTracker, $http) {
      postSpy = spyOn($http, 'post');
      eventTracker.event('login');
      eventTracker.save();
      expect(postSpy).toHaveBeenCalled();
      expect(postSpy.mostRecentCall.args[0]).not.toEqual('/track');
      expect(postSpy.mostRecentCall.args[0]).toEqual('/custom-track');
      expect(postSpy.mostRecentCall.args[1]).toEqual({ 'login': 1 });
    }));
  });
  

• factory(name, $getFn);

  Register a service factory, which will be called to return the service instance. This is short for registering a service where its provider consists of only a $get property, which is the given service factory function. You should use $provide.factory(getFn) if you do not need to configure your service in a provider.

  Parameters

  Param	Type	Details
  name	string	The name of the instance.
  $getFn	function()Array.<(string|function())>	The injectable $getFn for the instance creation. Internally this is a short hand for $provide.provider(name, {$get: $getFn}).

  Returns

  Object

  registered provider instance

  Examples

  Here is an example of registering a service

  $provide.factory('ping', ['$http', function($http) {
    return function ping() {
      return $http.send('/ping');
    };
  }]);
  

  You would then inject and use this service like this:

  someModule.controller('Ctrl', ['ping', function(ping) {
    ping();
  }]);
  

• service(name, constructor);

  Register a service constructor, which will be invoked with new to create the service instance. This is short for registering a service where its provider's $get property is a factory function that returns an instance instantiated by the injector from the service constructor function.

  Internally it looks a bit like this:

  {
    $get: function() {
      return $injector.instantiate(constructor);
    }
  }
  

  You should use $provide.service(class) if you define your service as a type/class.

  Parameters

  Param	Type	Details
  name	string	The name of the instance.
  constructor	function()Array.<(string|function())>	An injectable class (constructor function) that will be instantiated.

  Returns

  Object

  registered provider instance

  Examples

  Here is an example of registering a service using $provide.service(class).

  var Ping = function($http) {
    this.$http = $http;
  };
  
  Ping.$inject = ['$http'];
  
  Ping.prototype.send = function() {
    return this.$http.get('/ping');
  };
  $provide.service('ping', Ping);
  

  You would then inject and use this service like this:

  someModule.controller('Ctrl', ['ping', function(ping) {
    ping.send();
  }]);
  

• value(name, value);

  Register a value service with the $injector, such as a string, a number, an array, an object or a function. This is short for registering a service where its provider's $get property is a factory function that takes no arguments and returns the value service. That also means it is not possible to inject other services into a value service.

  Value services are similar to constant services, except that they cannot be injected into a module configuration function (see angular.Module) but they can be overridden by an Angular decorator.

  Parameters

  Param	Type	Details
  name	string	The name of the instance.
  value	*	The value.

  Returns

  Object

  registered provider instance

  Examples

  Here are some examples of creating value services.

  $provide.value('ADMIN_USER', 'admin');
  
  $provide.value('RoleLookup', { admin: 0, writer: 1, reader: 2 });
  
  $provide.value('halfOf', function(value) {
    return value / 2;
  });
  

• constant(name, value);

  Register a constant service with the $injector, such as a string, a number, an array, an object or a function. Like the value, it is not possible to inject other services into a constant.

  But unlike value, a constant can be injected into a module configuration function (see angular.Module) and it cannot be overridden by an Angular decorator.

  Parameters

  Param	Type	Details
  name	string	The name of the constant.
  value	*	The constant value.

  Returns

  Object

  registered instance

  Examples

  Here a some examples of creating constants:

  $provide.constant('SHARD_HEIGHT', 306);
  
  $provide.constant('MY_COLOURS', ['red', 'blue', 'grey']);
  
  $provide.constant('double', function(value) {
    return value * 2;
  });
  

• decorator(name, decorator);

  Register a decorator function with the $injector. A decorator function intercepts the creation of a service, allowing it to override or modify the behavior of the service. The return value of the decorator function may be the original service, or a new service that replaces (or wraps and delegates to) the original service.

  You can find out more about using decorators in the decorators guide.

  Parameters

  Param	Type	Details
  name	string	The name of the service to decorate.
  decorator	function()Array.<(string|function())>	This function will be invoked when the service needs to be provided and should return the decorated service instance. The function is called using the injector.invoke method and is therefore fully injectable. Local injection arguments: $delegate - The original service instance, which can be replaced, monkey patched, configured, decorated or delegated to.

  Examples

  Here we decorate the $log service to convert warnings to errors by intercepting calls to $log.warn().

  $provide.decorator('$log', ['$delegate', function($delegate) {
    $delegate.warn = $delegate.error;
    return $delegate;
  }]);