This is a sample Angular service, designed to expose only as much as desired and to be able to easily call "public" and "private" functions easily from within the service.

Angular Service

myApp.factory('MyService', function($http, $q) {
  //Local vars
  var state = {};
  
  //Publicly exposed functions
  var me = function() {};
  me.prototype = {
  
    getState: function(key) {
      return state[key];
    },
    
    save: function(key) {
      var deferred = $q.defer(),
          options = this.getState(key);
      
      doRequest(options).then(
        function(data, status, headers) {
          //Do work
          d.resolve(data);
        },
        function(data, status, headers) {
          d.reject(data);      
        }
      );
      
      return deferred.promise;
    }
    
  };
  
  //Private helper functions
  function doRequest(options) {
    return $http(options);
  }
  
  return new me();
});

Combine var maybe?