Questions tagged [angular-promise]
Angular's $q promises provide a powerful abstraction over flow control. If you tag your question with this tag, consider also tagging it with "promise" tag. This tag is also appropriate for questions about angular and promises not relaying to $q directly.
angular-promise
2,115
questions
1875
votes
35
answers
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views
What is the difference between Promises and Observables?
What is the difference between Promise and Observable in Angular?
An example on each would be helpful in understanding both the cases. In what scenario can we use each case?
- 18.8k
487
votes
10
answers
222k
views
AngularJS : Initialize service with asynchronous data
I have an AngularJS service that I want to initialize with some asynchronous data. Something like this:
myModule.service('MyService', function($http) {
var myData = null;
$http.get('data....
- 11.4k
279
votes
14
answers
718k
views
How can I access the value of a promise?
I'm looking at this example from Angular's documentation for $q, but I think this probably applies to promises in general. The example below is copied verbatim from their documentation with their ...
196
votes
8
answers
131k
views
How to cancel an $http request in AngularJS?
Given a Ajax request in AngularJS
$http.get("/backend/").success(callback);
what is the most effective way to cancel that request if another request is launched (same backend, different parameters ...
- 20.2k
113
votes
1
answer
30k
views
Does never resolved promise cause memory leak?
I have a Promise. I created it to cancel an AJAX request if needed. But since I don't need to cancel that AJAX, I've never resolved it and AJAX completed successfully.
A simplified snippet:
var ...
- 3,506
108
votes
6
answers
109k
views
Wait for all promises to resolve
So I have a situation where I have multiple promise chains of an unknown length. I want some action to run when all the CHAINS have been processed. Is that even possible? Here is an example:
app....
- 6,147
76
votes
11
answers
135k
views
Angular 1.6.0: "Possibly unhandled rejection" error [duplicate]
We have a pattern for resolving promises in our Angular app that has served us well up until Angular 1.6.0:
resource.get().$promise
.then(function (response) {
// do something ...
- 1,065
74
votes
4
answers
82k
views
angular $q, How to chain multiple promises within and after a for-loop
I want to have a for-loop which calls async functions each iteration.
After the for-loop I want to execute another code block, but not before all the previous calls in the for-loop have been resolved....
- 1,525
67
votes
6
answers
118k
views
Error handling in AngularJS http get then construct
How can I handle an HTTP error, e.g. 500, when using the AngularJS "http get then" construct (promises)?
$http.get(url).then(
function(response) {
console.log('get',response)
}
)
...
- 4,669
66
votes
7
answers
48k
views
What happens with $q.all() when some calls work and others fail?
What happens with $q.all() when some calls work and others fail?
I have the following code:
var entityIdColumn = $scope.entityType.toLowerCase() + 'Id';
var requests = $scope.grid.data
...
- 24k
58
votes
1
answer
78k
views
javascript, promises, how to access variable this inside a then scope [duplicate]
I want to be able to call a function inside the .then scope, and for that I use the this.foo() manner. But if I do this inside the .then I get an error, since this appears to be lost. What can I do?
...
- 4,181
50
votes
7
answers
121k
views
How to return a resolved promise from an AngularJS Service using $q?
My service is:
myApp.service('userService', [
'$http', '$q', '$rootScope', '$location', function($http, $q, $rootScope, $location) {
var deferred;
deferred = $q.defer();
this....
- 513
45
votes
2
answers
9k
views
How do I use Bluebird with Angular?
I tried using Angular with Bluebird promises:
HTML:
<body ng-app="HelloApp">
<div ng-controller="HomeController">{{name}} {{also}}</div>
</body>
JS:
// ...
- 274k
43
votes
2
answers
30k
views
How to handle error in angular-ui-router's resolve
I am using angular-ui-router's resolve to get data from server before moving to a state. Sometimes the request to the server fails and I need to inform the user about the failure. If I call the server ...
- 24.3k
41
votes
4
answers
44k
views
Get state of Angular deferred?
With jQuery deferreds I'm used to be able to check the current state like this:
var defer = $.Deferred();
defer.state(); //Returns the state of the deferred, eg 'resolved'
Is there a way to do the ...
- 3,592
35
votes
3
answers
13k
views
Caching a promise object in AngularJS service
I want to implement a dynamic loading of a static resource in AngularJS using Promises. The problem: I have couple components on page which might (or not, depends which are displayed, thus dynamic) ...
- 7,667
33
votes
2
answers
41k
views
Angular2 Observable - Await multiple function calls before proceeding
I am trying to improve my knowledge of Angular2 by migrating an application currently written in Angular1/AngularJS.
One feature in particular has me stumped. I am trying to replicate a feature where ...
33
votes
9
answers
59k
views
Possibly unhandled rejection in Angular 1.6
I have a code with AngularJS:
service.doSomething()
.then(function(result) {
//do something with the result
});
In AngularJS 1.5.9 when I have error in the .then() section like:
service....
- 4,325
30
votes
3
answers
8k
views
Angular $q .catch() method fails in IE8
I'm experiencing a weird bug on IE8 while trying to catch a promise reject (promise returned by a basic ngResource call) :
This code work with .then(success, fail) syntax :
promise.then(function(...
- 14.2k
29
votes
5
answers
27k
views
Immediately return a resolved promise using AngularJS
I'm trying to get my head around promises in JavaScript (in particular AngularJS).
I have a function in a service, let's call it fooService, that checks if we've loaded some data. If it has, I just ...
- 2,223
25
votes
3
answers
12k
views
$q promise error callback chains
In the following code snippet error 1 and success 2 will be logged. How can I can I propagate error callbacks being invoked rather than the success callbacks being invoked if the original deferred is ...
- 16.9k
25
votes
2
answers
20k
views
What's the equivalent of Angular's $q in Angular2?
What's the equivalent of Angular's $q in Angular2?
Specifically, I'm looking for $q.when, which allowed you to do something like:
return $q.when(['TestResponse']);
- 15.9k
21
votes
1
answer
3k
views
Intercept Unathorized API calls with Angular
I am trying to intercept the 401 and 403 errors to refresh the user token, but I can't get it working well. All I have achieved is this interceptor:
app.config(function ($httpProvider) {
$...
- 103
20
votes
2
answers
5k
views
Promises - error callback vs. catch
Can somebody tell me if there is a difference between using an error callback vs. a catch function, when using $q.promise please?
E.g. are the two snippets of code functionally equivalent?
function ...
- 6,212
19
votes
3
answers
6k
views
Typescript async/await and angular $q service
New TypeScript async/await feature uses ES6 promises. AngularJS uses $q service promises with slightly different interface.
Is there any way to use TypeScript async/await feature with $q service ...
- 3,917
18
votes
7
answers
65k
views
Make angular.forEach wait for promise after going to next object
I have a list of objects. The objects are passed to a deferred function. I want to call the function with the next object only after the previous call is resolved. Is there any way I can do this?
...
- 313
18
votes
3
answers
4k
views
Is this a "Deferred Antipattern"?
I'm finding it hard to understand the "deferred antipattern". I think I understand it in principal but I haven't seen a super simple example of what a service, with a differed promise and one with ...
- 1,432
18
votes
5
answers
16k
views
AngularJS - Promises rethrow caught exceptions
In the following code, an exception is caught by the catch function of the $q promise:
// Fiddle - http://jsfiddle.net/EFpn8/6/
f1().then(function(data) {
console.log("success 1: "+data)
...
- 12.6k
18
votes
5
answers
16k
views
Stop request in angularjs interceptor
How can I stop a request in Angularjs interceptor.
Is there any way to do that?
I tried using promises and sending reject instead of resolve !
.factory('connectionInterceptor', ['$q', '$timeout',...
- 634
18
votes
2
answers
44k
views
How can I access a variable outside a promise `.then` method?
I'm working on a Spotify app. I'm able to login and get my token. My problem is I cannot access a variable outside the method. In this case "getCurrentUser"
This is my method:
function getUser() {
...
- 427
18
votes
1
answer
13k
views
wait for promises in onbeforeunload
I want to send a $http.get if the page gets closed. Then I stumbold upon a problem where
promises can't get resolved because if this one last method returns, the page gets destroyed.
The following ...
- 183
17
votes
7
answers
31k
views
How do I sequentially chain promises with angularjs $q?
In the promise library Q, you can do the following to sequentially chain promises:
var items = ['one', 'two', 'three'];
var chain = Q();
items.forEach(function (el) {
chain = chain.then(foo(el));
})...
- 3,313
17
votes
3
answers
19k
views
Chain Angular $http calls properly?
I have been reading about $q and promises for days now and I seem to understand it...somewhat. I have the following situation in practice:
An $http request is made and checks whether a subsequent ...
- 12.1k
17
votes
3
answers
8k
views
finally block in angular 2 promise
I observe that In angular 2 there is no finally block for promise API
angular 1 :
loadUsers() {
fetch('/api/users').then((response) => {
return response.json();
}).then((data) => {
...
- 1,279
16
votes
3
answers
23k
views
Setting a timeout for each promise within a promise.all
I am able to successfully perform a Promise.all, and gracefully handle resolves and rejects. However, some promises complete within a few milliseconds, some can/could take a while.
I want to be able ...
- 8,613
16
votes
3
answers
15k
views
Promise chaining when using $timeout
I'm trying to understand the promise API and chaining, particularly the timing when $timeoutis used with .then(). What I had expected from the following is that since $timeout returns a promise, .then(...
- 648
14
votes
3
answers
3k
views
Why do we prefer using $q in angular instead of $http [duplicate]
I am currently using $q service from angular to make API calls like this:
var deferred = $q.defer();
$http.get(config.apiHost + details.url)
.success(function (data) {
deferred.resolve(...
- 2,124
14
votes
3
answers
13k
views
Swallowed message : Error: Uncaught (in promise): [object Undefined]
My login component briefly displays before being removed by an error message about an undefined object in a promise.
Here is the promise definition:
static init(): Promise<any> {
...
- 12.3k
13
votes
5
answers
38k
views
Subscription to promise
In my Angular 7 application I have next function:
getUserData(uid) {
return this.fireStore.collection('users').doc(uid).valueChanges().subscribe(data => {
this.writeCookie(data)
...
- 3,611
13
votes
4
answers
92k
views
Convert promise in JSON object
I have a problem converting the promise returned by the service to the controller. What I want is to create an array of JSON objects from the data contained in promise. Here is what I receive in the ...
- 173
13
votes
3
answers
8k
views
How to destroy unresolved promise
Have a look into the code snippet
$scope.getSongs = function(keyword){
songServices.getSongList(keyword).then(
function(resp){
$scope.songList = resp.data.songList;
...
- 392
13
votes
1
answer
7k
views
angular $http / jquery complete equivalent
Is there a way to emulate jquery 'complete' callback with angular $http module? I have some code I would like to execute no matter whether the request succeeded or failed and at the moment I find ...
- 4,638
12
votes
3
answers
11k
views
Angular promise on multiple $http
I am trying to do multiple $http call and my code looks something like this:
var data = ["data1","data2","data3"..."data10"];
for(var i=0;i<data.length;i++){
$http.get("http://example.com/"+...
- 19.2k
12
votes
3
answers
12k
views
What is the HTTP promise object in AngularJS?
Although I am working with the HTTP promise object in AngularJS, I don't have a clear concept of what an HTTP promise object actually is and what the is difference between an HTTP promise object and a ...
- 31.1k
12
votes
1
answer
12k
views
Executing then after catch
I have the following fiddle:
http://jsfiddle.net/thelgevold/3uv9nnjm/6/
angular.module('hello',[]).controller('helloController',function($q){
console.clear();
function someService(){
...
- 38.9k
12
votes
3
answers
22k
views
AngularJS $http call in a Service, return resolved data, not promises
I want to know if it is possible to make a service call that uses $http so it returns data directly without returning a promise? I have tried to use the $q and defer without any luck.
Here is what I ...
- 3,893
12
votes
2
answers
4k
views
Injecting a resolved promise into service
I need to get some information (a schema) from the server before I set up a bunch of services that depend on that information.
My server provides a schema that defines various properties of a model. ...
- 715
11
votes
2
answers
28k
views
AngularJs console.log "$q is not defined"
I am getting this error in the console $q is not defined. When I did some research I found some thing like .q library has been deprecated from
http://www.breezejs.com/documentation/breeze-labs/...
- 5,455
11
votes
1
answer
18k
views
Angular 6 Async-await not working on http request
Hi im using angular 6 to call a rest api with the code below. I am trying to acheive making the code synchronous with the async-await function. however something is missing
async save() {
if (...
- 509
11
votes
4
answers
9k
views
Javascript: How to iterate on array using promises?
LIVE DEMO
Given the following function:
function isGood(number) {
var defer = $q.defer();
$timeout(function() {
if (<some condition on number>) {
defer.resolve();
} else {
...
- 169k