Return promise in AngularJS $http.get?

Question

I'm trying to return the values I get in my $http.get but I can't get it to work...

$scope.getDecision = function(id) {
    var defer = $q.defer();
    $http({
        method: 'GET',
        url: 'http://127.0.0.1:3000/decision',
        params: {id: id},
        headers: {'Content-Type': 'application/x-www-form-urlencoded'}
    }).success(function(data, status, header, config) {
        console.log(data); //----> Correct values
        defer.resolve(data);
    }).error(function(data, status, header, config) {
        defer.reject("Something went wrong when getting decision);
    });
    return defer.promise;
};

$scope.selectView = function(id) {
     var decision = $scope.getDecision(id);
     console.log(decision); //----> undefined
}

When I call selectView I want to get a decision, but all I get is undefined... Have I misunderstood the promise pattern? :S

Yes, promises are still asynchronous. You cannot `return` a simple value — Bergi, Apr 24 '15 at 14:02
possible duplicate of [Issue with asynchronous function and scope of javascript variable](http://stackoverflow.com/questions/27506970/issue-with-asynchronous-function-and-scope-of-javascript-variable) — thomaux, Apr 24 '15 at 14:03
Except for the [deferred antipattern](http://stackoverflow.com/q/23803743/1048572), this should still log a promise object not `undefined`? — Bergi, Apr 24 '15 at 14:04

score 3 · Answer 1 · edited Apr 24 '15 at 14:07

3

$http itself returns a promise. No need to form your own, just do return $http(...).

edited Apr 24 '15 at 14:07

CodingIntrigue

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answered Apr 24 '15 at 14:01

David says Reinstate Monica

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I removed your `.get` call since OP is using `$http` with options object, hope you don't mind :) – CodingIntrigue Apr 24 '15 at 14:07

score 0 · Accepted Answer · answered Apr 24 '15 at 14:01

$http returns a Promise anyway, so you don't really need to create your own, but the main reason this isn't working is that you still need to .then your getDecision call in order to wait for the asynchronous operation to complete, e.g.

$scope.selectView = function(id) {
     $scope.getDecision(id).then(function(decision) {
          console.log(decision);
     });
}

To use the existing $http promise:

$scope.getDecision = function(id) {
    return $http({
        method: 'GET',
        url: 'http://127.0.0.1:3000/decision',
        params: {id: id},
        headers: {'Content-Type': 'application/x-www-form-urlencoded'}
    });
};

Return promise in AngularJS $http.get?

2 Answers2