Am trying to call a Post method and then depending on the result I am going to call same Post method multiple times and return the result, using $q.all.
My Post method is :
getData: function (params, callback) {
$http.post('service/myService', params)
.success(function (data) {
callback(null, data);
}).error(function (error) {
callback(error);
});
}
I am calling it in below function, this function is recursive so if it contains nextUrl I am doing same thing until there is no object for paging:
var result = [];
var promises = [];
var checkForPaging = function (nextUrl, service, $q) {
var deferred = $q.defer();
var criteria = {
url: url
}
var promise = service.getData(criteria, function (error, data) {
if (data.statusCode == 200) {
for (var i = 0; i < data.body.items.length; i++) {
result.push(data.body.items[i]);
}
if (data.body.paging != null && data.body.paging.next != null) {
checkForPaging(data.body.paging.next.url, service, $q);
} else{
deferred.resolve(result);
}
}
});
promises.push(promise);
$q.all(promises)
return deferred.promise;
}
Then am calling this function from below and want to get the result back once all calls are complete:
checkForPaging(data.body.paging.next.url, myService, $q).then(function (data) {
console.log(data)
});
The issue I am having is that it never hits the callback function above : console.log(data). But I can see it calling the Post method several times.
If I resolve it like below then I can see after first Post it is hitting the callback above:
$q.all(promises).then(function (results) {
deferred.resolve(result);
}, function (errors) {
deferred.reject(errors);
});
Am I doing it right? How can I get the result back and call the Post method several times?
Let me know if it is not clear or have any questions!
Here is solution: https://plnkr.co/edit/HqkFNo?p=preview I rewrited logic a bit. You can catch the main idea.
UPDATE added promiseless solution
1) Your service should return only promise:
this.getData = function(url, params){
return $http.post(url, params); //You're just returning promise
}
2) You don't need $q.all, you can use single promise:
var result = [];
var deferred;
var checkForPaging = function (url) {
if(!deferred){
deferred = $q.defer();
}
//resolvind service promise
newService.getData(url).then(
//if ok - 200
function(response){
for (var i = 0; i < data.body.items.length; i++) {
result.push(data.body.items[i]);
}
if (data.body.paging != null && data.body.paging.next != null){
{
return checkForPaging(data.body.paging.next.url);
} else{
deferred.resolve(result);
}
},
//handle errors here
function(error) {
}
);
return deferred.promise;
}
3) You should call it like this:
checkForPaging('url').then(function(data){
//here will be resolved promise
console.log(data);
});
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