unit test for angular responseError interceptor with 'notify' promise - angularjs

I have angular responseError interceptor, which implements logic of resending request to server if a previous attempt was unsuccessful. Moreover the interceptor returns 'notify' promise to keep in touch about current status.
return {
responseError: function(response) {
var retries = angular.isDefined(response.config.headers['X-RETRIES']) ? response.config.headers['X-RETRIES'] : 0;
response.config.headers['X-RETRIES'] = retries + 1;
if (response.config.headers['X-RETRIES'] <= MAX_XHR_ATTEMPTS) {
var $http = $injector.get('$http'),
defer = $q.defer();
$timeout(function() {
defer.notify('trying');
defer.resolve($http(response.config));
}, 1000);
return defer.promise;
} else {
return $q.reject(response);
}
}
};
}
It's example but it works properly, for unit tests I use tdd, mocha, chai, sinon. I used similar code: (the interceptor is injected in above code)
test('test', inject(function($http, ) {
$httpBackend.when('GET', '/test').respond(500);
var promise = $http.get('/test');
$httpBackend.flush();
promise.then(
function(data) {
dump('success', data);
},
function(data) {
dump('error', data);
},
function(data) {
dump('notify', data);
}
);
}));
But the promise doesn't return any state. if I tried to change interceptor to return 'reject' promise once as an error is occurred (without timeout and additional pull request) in this case everything works as expected. How to make test for the case?

You didn't flush the $timeout - try the following:
test('test', inject(function($http, $timeout) {
$httpBackend.when('GET', '/test').respond(500);
var promise = $http.get('/test');
$httpBackend.flush();
promise.then(
function(data) {
dump('success', data);
},
function(data) {
dump('error', data);
},
function(data) {
dump('notify', data);
}
);
// Timeout after we've attached notify listener.
$timeout.flush(1001);
}));

Related

Jasmine - How to Spy and test an AngularJS asynchronus Service

I am trying to spy on an asynchronous service call, however so far not successful. Though the synchronus calls are able to Mock.
commonService.getResource(ResourceConst).then(function (result) {
$scope.resource = result.data;
}, function (error) {
loggerService.log(error);
});
Actual Get Resource Function
function getResource(resourceURL) {
var deferred = $q.defer();
var url = resourceURL + ".json";
$http.get(url).then(function (data) {
deferred.resolve(data);
},
function (error) {
deferred.reject(error);
});
return deferred.promise;
}
Even though I was able to spy on synchronus methods in the same service like below I was not able to do the same for this function call.
spyOn(commonService, 'hasData').and.callFake(function(args) {
return true;
});
The above code success fully mocked the synchronus call ,
$scope.hasData = commonService.hasData($scope.resource.Data);
How can I return a result
{'name': "Name"} to the asynchronous call getResource
Since the service is supposed to return a promise, return value should be mocked with a promise:
spyOn(commonService, 'hasData').and.returnValue($q.resolve({'name': "Name"} ));
The code above uses deferred antipattern. It should be instead:
function getResource(resourceURL) {
var url = resourceURL + ".json";
return $http.get(url);
}

How to set a timeout to abort an $http.get() inside a factory or service?

I have the following method getData(url) in a my factory which uses $http.get(url) to get data from an URL
angular
.module('az-app')
.factory('WebServiceFactory', function ($http, $q) {
var WebServiceFactory = this;
WebServiceFactory.getData = function (url) {
var deferred = $q.defer();
$http.get(url)
.then(
function (response) {
deferred.resolve({
data: response
});
}, function (rejected) {
deferred.reject({
data: rejected
});
}
);
//Promise to be returned
return deferred.promise;
}
It works fine but I need to abort the http.get and/or reject the promise so I can display an error message from my controller which has this method:
var getSpecialties = function (type) {
doctorsCtrl.showLoading();
var url = "example.com";
WebServiceFactory.getData(url)
.then(
function (result) {
doctorsCtrl.hideLoading();
var specialtiesArray = result.data.data;
StorageFactory.specialties = specialtiesArray;
doctorsCtrl.specialties = StorageFactory.specialties
//I WANT TO TRIGGER THIS REJECTED FUNCTION when timeout time is finished
}, function (rejected) {
doctorsCtrl.hideLoading();
doctorsCtrl.showAlert();
}
);
}
The service $http accepts, in the config object, a timeout property that answers to what you need. Have a look at the documentation, especially the part about the config object:
timeout – {number|Promise} – timeout in milliseconds, or promise that should abort the request when resolved.
Also, notice that you're using promises in an inefficient way. The following is a promise antipattern:
WebServiceFactory.getData = function (url) {
var deferred = $q.defer();
$http.get(url)
.then(
function (response) {
deferred.resolve(...);
}, function (rejected) {
deferred.reject(...);
}
);
//Promise to be returned
return deferred.promise;
}
You could have simply:
WebServiceFactory.getData = function (url) {
return $http.get(url);
}
With a timeout of 3 seconds it would be:
Service:
WebServiceFactory.getData = function (url) {
return $http.get(url, {timeout: 3000}); // <-- timeout applies ONLY for this call
}
Controller:
WebServiceFactory.getData(url).then(
function (result) {
doctorsCtrl.hideLoading();
doctorsCtrl.specialties = StorageFactory.specialties = result.data;
}, function (rejected) {
doctorsCtrl.hideLoading();
doctorsCtrl.showAlert();
}
);
Notice also that you're calling hideLoading both in case of success and error. You can call it once, in a chained finally handler:
// ...
.finally(function () {
doctorsCtrl.hideLoading();
}

AngularJs cancel http request: application still waiting for response after cancel

In my application, I have a service called 'pendingRequests' that keeps track of my http requests. I configured my $httpProvider to use this service.
The purpose of this service is to give me the ability to cancel ALL pending http requests occurring in ANY controller.
Here is the code:
app.service('pendingRequests', function($rootScope, $q) {
var pending = [];
this.get = function() {
return pending;
};
this.add = function(request) {
pending.push(request);
//console.log("Pending Requests(before):" + pending);
};
this.remove = function(request) {
angular.forEach(pending, function(p , key) {
if(p.url == request.url) pending.splice(key, 1);
});
// console.log("Pending Requests(after):" + pending);
};
this.cancelAll = function() {
if(typeof pending !='undefined'){
angular.forEach(pending, function(p) {
p.canceller.resolve();
});
pending.length = 0;
}
};
});
app.config(function($httpProvider){
$httpProvider.interceptors.push(function($q, pendingRequests){
return {
'request': function (config){
var canceller = $q.defer();
pendingRequests.add({
url: config.url,
canceller: canceller
});
config.timeout = canceller.promise;
return config || $q.when(config);
},
'response': function (response){
pendingRequests.remove(response.config);
//pendingRequests remove request
return response;
}
}
});
});
The service is canceling the requests as intended. However, the next request submitted is delayed as if it is still waiting for another request to complete.
What is causing this delay?

Why isn't my $resource error handler called when I have a responseError interceptor?

I'm building my first Angular app, and I've run into a problem. I have an AngularJS resource whose .get I call with both a success and error callback, like so:
var new_uptime = Uptime.get({}, function(){
console.log("new_uptime", new_uptime, "$scope.uptime", $scope.uptime);
console.log("new_uptime.uptime", new_uptime.uptime);
if ($scope.uptime && new_uptime.uptime < $scope.uptime.uptime) {
console.log("Reboot detected");
location.reload(true);
}
$scope.uptime = new_uptime;
$timeout(reload_uptime, 5000);
}, function(response){
console.log("Failed to read uptime", response);
console.log("Retrying in 10s");
$scope.uptime = "[unknown]";
$timeout(reload_uptime, 10000);
});
I've tested this with various error statuses from the server, and it works fine. Now I'd like to add app-wide retrying on 503s. I've added a module for that, which looks like this:
retry_module = angular.module('service.retry', []);
retry_module.factory("retry", ["$q", "$injector", "$timeout", function($q, $injector, $timeout) {
return {
"responseError": function(rejection) {
console.log("Request failed", rejection);
if (rejection.status != 503) {
console.log("Unhandled status");
return $q.reject(rejection);
}
var delay = Math.floor(Math.random() * 1000);
console.log("Was 503, retrying in " + delay + "ms");
var deferred = $q.defer();
$timeout(function() {
var $http = $http || $injector.get("$http");
deferred.resolve($http(rejection.config));
}, delay);
return deferred;
}
};
}]);
retry_module.config(["$httpProvider", function ($httpProvider) {
$httpProvider.interceptors.push("retry");
}]);
This works well for retrying on 503s, and successful attempts are handled by the success callback in the Uptime.get caller, as intended. However, if the server returns some other error, then I get the "Unhandled status" printout, but then neither "new_uptime" nor "Failed to read uptime". Where did my rejection go, and how do I go about trouble-shooting issues like this?
You need to return the promise, not the deferred. So the end of your responseError handler should be:
var deferred = $q.defer();
$timeout(function() {
var $http = $http || $injector.get("$http");
deferred.resolve($http(rejection.config));
}, delay);
return deferred.promise;

How to cancel an $http request in AngularJS?

Given a Ajax request in AngularJS
$http.get("/backend/").success(callback);
what is the most effective way to cancel that request if another request is launched (same backend, different parameters for instance).
This feature was added to the 1.1.5 release via a timeout parameter:
var canceler = $q.defer();
$http.get('/someUrl', {timeout: canceler.promise}).success(successCallback);
// later...
canceler.resolve(); // Aborts the $http request if it isn't finished.
Cancelling Angular $http Ajax with the timeout property doesn't work in Angular 1.3.15.
For those that cannot wait for this to be fixed I'm sharing a jQuery Ajax solution wrapped in Angular.
The solution involves two services:
HttpService (a wrapper around the jQuery Ajax function);
PendingRequestsService (tracks the pending/open Ajax requests)
Here goes the PendingRequestsService service:
(function (angular) {
'use strict';
var app = angular.module('app');
app.service('PendingRequestsService', ["$log", function ($log) {
var $this = this;
var pending = [];
$this.add = function (request) {
pending.push(request);
};
$this.remove = function (request) {
pending = _.filter(pending, function (p) {
return p.url !== request;
});
};
$this.cancelAll = function () {
angular.forEach(pending, function (p) {
p.xhr.abort();
p.deferred.reject();
});
pending.length = 0;
};
}]);})(window.angular);
The HttpService service:
(function (angular) {
'use strict';
var app = angular.module('app');
app.service('HttpService', ['$http', '$q', "$log", 'PendingRequestsService', function ($http, $q, $log, pendingRequests) {
this.post = function (url, params) {
var deferred = $q.defer();
var xhr = $.ASI.callMethod({
url: url,
data: params,
error: function() {
$log.log("ajax error");
}
});
pendingRequests.add({
url: url,
xhr: xhr,
deferred: deferred
});
xhr.done(function (data, textStatus, jqXhr) {
deferred.resolve(data);
})
.fail(function (jqXhr, textStatus, errorThrown) {
deferred.reject(errorThrown);
}).always(function (dataOrjqXhr, textStatus, jqXhrErrorThrown) {
//Once a request has failed or succeeded, remove it from the pending list
pendingRequests.remove(url);
});
return deferred.promise;
}
}]);
})(window.angular);
Later in your service when you are loading data you would use the HttpService instead of $http:
(function (angular) {
angular.module('app').service('dataService', ["HttpService", function (httpService) {
this.getResources = function (params) {
return httpService.post('/serverMethod', { param: params });
};
}]);
})(window.angular);
Later in your code you would like to load the data:
(function (angular) {
var app = angular.module('app');
app.controller('YourController', ["DataService", "PendingRequestsService", function (httpService, pendingRequestsService) {
dataService
.getResources(params)
.then(function (data) {
// do stuff
});
...
// later that day cancel requests
pendingRequestsService.cancelAll();
}]);
})(window.angular);
Cancelation of requests issued with $http is not supported with the current version of AngularJS. There is a pull request opened to add this capability but this PR wasn't reviewed yet so it is not clear if its going to make it into AngularJS core.
If you want to cancel pending requests on stateChangeStart with ui-router, you can use something like this:
// in service
var deferred = $q.defer();
var scope = this;
$http.get(URL, {timeout : deferred.promise, cancel : deferred}).success(function(data){
//do something
deferred.resolve(dataUsage);
}).error(function(){
deferred.reject();
});
return deferred.promise;
// in UIrouter config
$rootScope.$on('$stateChangeStart', function (event, toState, toParams, fromState, fromParams) {
//To cancel pending request when change state
angular.forEach($http.pendingRequests, function(request) {
if (request.cancel && request.timeout) {
request.cancel.resolve();
}
});
});
For some reason config.timeout doesn't work for me. I used this approach:
let cancelRequest = $q.defer();
let cancelPromise = cancelRequest.promise;
let httpPromise = $http.get(...);
$q.race({ cancelPromise, httpPromise })
.then(function (result) {
...
});
And cancelRequest.resolve() to cancel. Actually it doesn't not cancel a request but you don't get unnecessary response at least.
Hope this helps.
This enhances the accepted answer by decorating the $http service with an abort method as follows ...
'use strict';
angular.module('admin')
.config(["$provide", function ($provide) {
$provide.decorator('$http', ["$delegate", "$q", function ($delegate, $q) {
var getFn = $delegate.get;
var cancelerMap = {};
function getCancelerKey(method, url) {
var formattedMethod = method.toLowerCase();
var formattedUrl = encodeURI(url).toLowerCase().split("?")[0];
return formattedMethod + "~" + formattedUrl;
}
$delegate.get = function () {
var cancelerKey, canceler, method;
var args = [].slice.call(arguments);
var url = args[0];
var config = args[1] || {};
if (config.timeout == null) {
method = "GET";
cancelerKey = getCancelerKey(method, url);
canceler = $q.defer();
cancelerMap[cancelerKey] = canceler;
config.timeout = canceler.promise;
args[1] = config;
}
return getFn.apply(null, args);
};
$delegate.abort = function (request) {
console.log("aborting");
var cancelerKey, canceler;
cancelerKey = getCancelerKey(request.method, request.url);
canceler = cancelerMap[cancelerKey];
if (canceler != null) {
console.log("aborting", cancelerKey);
if (request.timeout != null && typeof request.timeout !== "number") {
canceler.resolve();
delete cancelerMap[cancelerKey];
}
}
};
return $delegate;
}]);
}]);
WHAT IS THIS CODE DOING?
To cancel a request a "promise" timeout must be set.
If no timeout is set on the HTTP request then the code adds a "promise" timeout.
(If a timeout is set already then nothing is changed).
However, to resolve the promise we need a handle on the "deferred".
We thus use a map so we can retrieve the "deferred" later.
When we call the abort method, the "deferred" is retrieved from the map and then we call the resolve method to cancel the http request.
Hope this helps someone.
LIMITATIONS
Currently this only works for $http.get but you can add code for $http.post and so on
HOW TO USE ...
You can then use it, for example, on state change, as follows ...
rootScope.$on('$stateChangeStart', function (event, toState, toParams) {
angular.forEach($http.pendingRequests, function (request) {
$http.abort(request);
});
});
here is a version that handles multiple requests, also checks for cancelled status in callback to suppress errors in error block. (in Typescript)
controller level:
requests = new Map<string, ng.IDeferred<{}>>();
in my http get:
getSomething(): void {
let url = '/api/someaction';
this.cancel(url); // cancel if this url is in progress
var req = this.$q.defer();
this.requests.set(url, req);
let config: ng.IRequestShortcutConfig = {
params: { id: someId}
, timeout: req.promise // <--- promise to trigger cancellation
};
this.$http.post(url, this.getPayload(), config).then(
promiseValue => this.updateEditor(promiseValue.data as IEditor),
reason => {
// if legitimate exception, show error in UI
if (!this.isCancelled(req)) {
this.showError(url, reason)
}
},
).finally(() => { });
}
helper methods
cancel(url: string) {
this.requests.forEach((req,key) => {
if (key == url)
req.resolve('cancelled');
});
this.requests.delete(url);
}
isCancelled(req: ng.IDeferred<{}>) {
var p = req.promise as any; // as any because typings are missing $$state
return p.$$state && p.$$state.value == 'cancelled';
}
now looking at the network tab, i see that it works beatuifully. i called the method 4 times and only the last one went through.
You can add a custom function to the $http service using a "decorator" that would add the abort() function to your promises.
Here's some working code:
app.config(function($provide) {
$provide.decorator('$http', function $logDecorator($delegate, $q) {
$delegate.with_abort = function(options) {
let abort_defer = $q.defer();
let new_options = angular.copy(options);
new_options.timeout = abort_defer.promise;
let do_throw_error = false;
let http_promise = $delegate(new_options).then(
response => response,
error => {
if(do_throw_error) return $q.reject(error);
return $q(() => null); // prevent promise chain propagation
});
let real_then = http_promise.then;
let then_function = function () {
return mod_promise(real_then.apply(this, arguments));
};
function mod_promise(promise) {
promise.then = then_function;
promise.abort = (do_throw_error_param = false) => {
do_throw_error = do_throw_error_param;
abort_defer.resolve();
};
return promise;
}
return mod_promise(http_promise);
}
return $delegate;
});
});
This code uses angularjs's decorator functionality to add a with_abort() function to the $http service.
with_abort() uses $http timeout option that allows you to abort an http request.
The returned promise is modified to include an abort() function. It also has code to make sure that the abort() works even if you chain promises.
Here is an example of how you would use it:
// your original code
$http({ method: 'GET', url: '/names' }).then(names => {
do_something(names));
});
// new code with ability to abort
var promise = $http.with_abort({ method: 'GET', url: '/names' }).then(
function(names) {
do_something(names));
});
promise.abort(); // if you want to abort
By default when you call abort() the request gets canceled and none of the promise handlers run.
If you want your error handlers to be called pass true to abort(true).
In your error handler you can check if the "error" was due to an "abort" by checking the xhrStatus property. Here's an example:
var promise = $http.with_abort({ method: 'GET', url: '/names' }).then(
function(names) {
do_something(names));
},
function(error) {
if (er.xhrStatus === "abort") return;
});

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