Angular: update scope with async AJAX data from a factory - ajax

What's the recommended way to do this?
1.
factory.updater = function(varObjToBeUpdated){
$http.post('/url', {})
.success(function(data){
for (data_field in data)
varObjToBeUpdated[data_field] = data[data_field];
});
}
...
myFactory.updater($scope.varObjToBeUpdated);
Or 2.,
myFactory.updater().success(function(data, ..){
$scope.varObjToBeUpdated = data;
});
...
factory.updater = function(){
return $http.post('/url', {});
}
Is it ok to to pass a reference scope variable to a factory? I always thought factories as delivering data.
And what's wrong with the second method (if it's less acceptable)?

I prefer the second approach, as this allows you to just inject the service when you need it across multiple controllers. Use .then to continue the promise pattern:
myFactory.updater().then(function(data, ..){
$scope.varObjToBeUpdated = data;
});
app.factory('myFactor', function($http) {
return {
updater: function() {
return $http({'/url',}).then(function(result) {
return result.data;
});
}
}
});

Related

How to get the data from BehaviorSubject after its completed?

I have a function that returns a BehaviorSubject but when I try to use the data I get back from the function I need to use it once all the data is back, is there a way to know when the BehaviorSubject is done pulling all the data?
I tried using .finally but it never gets called. Here is the code I'm using.
getData() {
let guideList = '';
this.getChildren(event.node)
.subscribe(
function(data) {
console.log('here');
guideList = data.join(',');
},
function(err) {
console.log('error');
},
function() {
console.log('done');
console.log(guideList);
}
);
}
getChildren(node: TreeNode) {
const nodeIds$ = new BehaviorSubject([]);
//doForAll is a promise
node.doForAll((data) => {
nodeIds$.next(nodeIds$.getValue().concat(data.id));
});
return nodeIds$;
}
Attached is a screen shot of the console.log
Easiest way is to just collect all the data in the array and only call next once the data is all collected. Even better: don't use a subject at all. It is very rare that one ever needs to create a subject. Often people use Subjects when instead they should be using a more streamlined observable factory method or operator:
getChildren(node: TreeNode) {
return Observable.defer(() => {
const result = [];
return node.doForAll(d => result.push(d.id)).then(() => result);
});
}

.then is not a function Angularjs factory

I just started learning Jasmine test cases for angularjs. I am unable to test below code.Kindly help
$scope.getConstants = function(lovName) {
ConstantService.getConstants(lovName).then(function(d) {
switch (lovName) {
case 'WORKFLOW':
$scope.workflowTypes = d;
$scope.loadCounterpartyTmp();
break;
--------Other Cases
}
My ConstantService is defined as
App.factory('ConstantService', [ '$http', '$q', function($http, $q) {
return {
getConstants : function(lovName) {
return $http.post('/sdwt/data/getConstants/', lovName).then(function(response) {
return response.data;
}, function(errResponse) {
return $q.reject(errResponse);
});
}
I want to test getConstants function.I need to create a mock of ConstantService and pass the data to it.
I have written below test case but the test case is not working.Please let me know how to test the above code
describe('getConstantsForMurexEntity', function() {
it('testing getConstantsForMurexEntity function', function() {
var d=[];
d.push(
{id:1,value:'ABC'},
{id:2,value:'DEF'},
{id:3,value:'IJK'},
{id:4,value:'XYZ'},
);
//defined controller
spyOn(ConstantService, 'getConstants').and.returnValue(d);
$scope.getConstants('WORKFLOW');
expect($scope.workflowTypes).toBe(d);
The above test case is not working as it is saying "ConstantService.getConstants(...).then is not a function".
Your ConstantService.getConstants() function returns a promise, which your actual code is using, with the .then() call. This means means that when you spy on it, you also need to return a promise, which you are not doing. Because you are not returning a promise, when your actual call tries to call .then(), it is undefined, which is the reason for the error message.
Also, you aren't using Array.push correctly.
Your test should probably look something like the following (note, this is untested):
describe('getConstantsForMurexEntity', function() {
it('should set workflowTypes to the resolved value when lovName is "WORKFLOW"', inject(function($q) {
var deferred = $q.defer();
spyOn(ConstantService, 'getConstants').and.returnValue(deferred.promise);
var d = [
{id:1,value:'ABC'},
{id:2,value:'DEF'},
{id:3,value:'IJK'},
{id:4,value:'XYZ'},
];
$scope.getConstants('WORKFLOW');
deferred.resolve(d);
$scope.$apply();
expect($scope.workflowTypes).toBe(d);
}));
});

Async call in beforeAll

Here are 2 samples of the same test. The only difference is that first one uses a promise in beforeAll block to assign a value to the variable while the second one assigns the value directly.
I raised a similar question Running spec after promise has been resolved with one of the comments pointing to this issue https://github.com/jasmine/jasmine/issues/412 which says that this is not supported in Jasmine. Has somebody figured out any workaround?
This fails with TypeError: Cannot read property 'forEach' of undefined
describe('Async car test', function () {
var cars;
beforeAll(function (done) {
// getCars() is a promise which resolves to ['audi', 'bmw']
getCars().then(function (data) {
cars = data;
console.log(cars) // ['audi', 'bmw']
done();
});
});
cars.forEach(function (car) {
it('car ' + car, function () {
expect(car).toBe(car);
});
});
});
This works fine
describe('Car test', function () {
var cars = ['audi', 'bmw'];
cars.forEach(function (car) {
it('car ' + car, function () {
expect(car).toBe(car);
});
});
});
Posting it as an answer, because I can't see things properly in comments.
I'm actually generating tests in my spec as well, and I'm using https://www.npmjs.com/package/jasmine-data-provider , I think you probably cannot generate it directly from resolved promise. And wrapping in another it doesn't work for you. This should work:
var using = require('jasmine-data-provider');
using(cars.forEach, function (car) {
it(car + ' should be' + car, function () {
expect(car).toBe(car);
});
});
This is not an issue with jasmine, it is an issue with your code.
beforeAll does not block subsequent code below the statement. it blocks code that is defined in it('should ...', (done)=>{...});
it('should have cars', (done) => {
cars.forEach(function (car) {
expect(car).toBe(car);
});
});
Since Jasmine does not support adding tests at runtime, the trick is to request the asynchronous data before starting Jasmine, and then using the retrieved data during runtime instead. This can be achieved with a singleton and programmatically starting Jasmine.
See here for a working example.
// car-collection.js
class CarCollection {
static load() {
return this.request()
then((data) => this.cars = data);
}
static request() {
// in practice this function would do something cooler
return Promise.resolve(['audi', 'bmw']);
}
}
modules.export = CarCollection;
Since CarCollection has methods that are static they will be shared across imports and this.cars will persist.
// launcher.js
const Jasmine = require('jasmine');
const CarCollection = require('./car-collection');
CarCollection.load()
.then(() => {
console.log(`car count is ${CarCollection.cars.length}`); // prints: car count is 2
const jasmine = new Jasmine();
jasmine.loadConfigFile(...); // path to jasmine.json
jasmine.execute();
});
An important step here is configure jasmine to know where to look for the test files. Either by loading a config or passing specifics into the execute function.
// car.spec.js
const CarCollection = require('./car-collection');
describe('test', function () {
CarCollection.cars.forEach((car) => {
it('test' + car, () => {
expect(car).toBe(car);
});
});
});
Now run node ./launcher.js and the tests should run.

How to deal with async requests in Marionette?

I am trying to fill in an ItemView in Marionette with the combined results of 2 API requests.
this.standings = App.request('collection:currentStandings');
this.userInfo = App.request('model:userInfo');
this.standings.each(function(s) {
if (s.currentUser) {
s.set('alias', this.userInfo.alias);
s.set('imageURL', this.userInfo.imageURL);
}
});
userInfoView = new LeagueBar.UserInfo({ collection: this.standings });
The problem is, the combination never happens because the requests have not been fulfilled before I try to combine them.
I know I probably need to add a promise for each request, but I haven't been able to find a clean way to do it. I could make 'collection:currentStandings' and 'model:userInfo' return promises, however, they are currently used in many other parts of the code, so I would have to go back and add .then()s and .done()s all over the code base where they weren't required before.
Any ideas or suggestions?
EDIT:
I have currently solved this in a less-than-ideal way: I created a template/view for the alias and a template/view for the imageURL and kept the template/view for the standings info. This doesn't seem like the best way and I'm interested to know the right way to solve this problem.
here are the two requests I am trying to combine:
Models.CurrentStandings = App.Collection.extend({
model: Models.PlayerStandings,
url: function() { return 'leagues/' + App.state.currentLeague + '/standings'; },
parse: function(standings) {
return _.map(standings, function(s) {
if (s.memberId == App.user.id)
s.currentUser = true;
return s;
});
}
});
App.reqres.setHandler('collection:currentStandings', function() {
weekStandings = new Models.CurrentStandings();
weekStandings.fetch({ success: function(data){ console.log(data); }});
return weekStandings;
});
Models.UserInfo = App.Model.extend({
url: 'users/me'
});
App.reqres.setHandler('model:userInfo', function(options) {
myuser = new Models.UserInfo();
myuser.fetch(options);
return myuser;
});
There are 2 solutions which based on your dependencies among views can be selected:
You can create views which are handling 'change' event of Models.UserInfo and when the data is ready (Change/Reset event raised) re-render the content. It is probably your solution.
If you are looking for a solution which should not create instance of LeageBar.UserInfo until both Models.CurrentStanding and Models.UserInfo are ready, you have to return the result of fetch function, so you may remove calling fetch from setHandlers and use them as following:
this.standings = App.request('collection:currentStandings');
this.userInfo = App.request('model:userInfo');
var that=this;
that.standings.fetch().done(function(){
that.userInfo.fetch().done(function(){
that.standings.each(function(s) {
if (s.currentUser) {
//....
}
});
userInfoView = new LeagueBar.UserInfo({ collection: that.standings });
});

Deferred Promises with AJAX in Angular

I'm trying to send data to my view from an AJAX call to my API. I am able to successfully hit my API and get data, but I was having problems with the view rendering before the AJAX call came back.
I'm trying to wrap my AJAX call in a Promise but it's not working. Here's my layout
Controller
.controller('DashCtrl', function($scope, Tweets) {
$scope.tweets = Tweets.all()
})
Factory doing ajax call
.factory('Tweets', function($http) {
$http.get('http://localhost:3000/tweets')
.success(function(data) {
var tweets = data
debugger
})
return {
all: function() {
//should return the results of the AJAX call when it's complete
}
}
});
I've tried making wrapping the ajax call into a function and using .then(function(payload){ return payload.data }) - Payload.data has my data but its never returned when I call the function. I'm new to angular, so I would appreciate any help or insight.
You should define your factory as
.factory('Tweets', function($http) {
return {
all: function() {
return $http.get('http://localhost:3000/tweets')
.then(function(response) {
return reponse.data;
})
}
}
});
Then change your controller to
.controller('DashCtrl', function($scope, Tweets) {
Tweets.all().then(function(data) {
$scope.tweets = data;
});
})
Use the $resource service. The docs don't mention it, but comments in the source do.
$resolved: true after first server interaction is completed (either with success or rejection), false before that.
So in the controller:
$scope.tweets = $resource('/tweets').query()
And in the view:
<div ng-if="tweets.$resolved">
Loading data with ngResource or from factory promise callback are viable options, but there's one more way nobody mentioned yet: resolve data to controller via route definition. This approach allows to write simplistic controllers that don't know how to load data at all. In most cases it will be more than enough if you don't need to load data dynamically, like pagination or infinite scroll.
You will need to define route and resolve function:
angular
.module('app', ['ngRoute'])
.config(function ($routeProvider) {
$routeProvider
.when('/', {
controller: 'ctrl',
controllerAs: 'view',
templateUrl: 'view.html',
resolve: {
tweets: function (Tweets) {
return Tweets.all();
}
}
})
})
The tweets property on resolve will inject loaded data into controller as tweets, all you have to do is just assign received data:
.controller('ctrl', function (tweets) {
this.tweets = tweets;
});
In addition, here's how Tweets service might look like:
.factory('Tweets', function ($timeout) {
function all () {
return $timeout(function () {
return ["hey", "there"];
});
}
return {
all: all
};
})
Basically, it exposes methods that return promise, returning some data ($timeout returns promise too, so I've used it instead of $http for example purpose).
Full example on JS Bin.

Resources