angular seamless error-handling

angular-seamless-error-handling.js

// new version with service and $injector.get('nameOfService'); ??

// ERROR-HANDLING
.config(function ($provide, $httpProvider) {
  // error-interceptor
  $provide.factory('errorHandlerInterceptor', function ($q, $rootScope) {
    return {
      response: function (response) {
        // only handle remote XHR requests
        if (response.config.url.search(/\/\//) !== -1) {
          // handle custom error codes from backend maybe?
        }
        return response;
      },
      responseError: function (rejection) {
        // use broadcast and not service, since service can't depend on $http (circular dep)
        $rootScope.$broadcast('httpError', rejection);
        return $q.reject(rejection);
      }
    };
  });

  $httpProvider.interceptors.push('errorHandlerInterceptor');
})
// MESSAGING
.run(function ($rootScope, $timeout, $window) {

  var tolerance = 3000;
  var offset = 150;
  var errors = {};

  var getKey = function (rejection) {
    // build key based on url and http status
    return rejection.config.url + ':' + rejection.status;
  };
  var addError = function (rejection) {
    errors[getKey(rejection)] = rejection;
  };
  var deleteError = function (rejection) {
    delete errors[getKey(rejection)];
  };

  $rootScope.$on('httpError', function (event, rejection) {

    var errorKey = getKey(rejection);

    // don't treat same error several times within tolerance
    if (!errors[errorKey]) {
      addError(rejection);

      // wait a little to ensure no further change of message/cancellation
      $timeout(function () {
        if (errors[errorKey]) {
          // TODO: display error
          $window.alert(rejection.status);
        }
      }, offset);

      // delete error after tolerance
      $timeout(function () {
        deleteError(rejection);
      }, tolerance);
    }
  });

  $rootScope.$on('httpErrorCancel', function (event, rejection) {
    deleteError(rejection);
  });
})