Angular Resolution Verification

Question

Angular Resolution Verification

I'm currently working on making HTTP calls in Angular and I want to trigger a different service function if an error occurs. The problem is, no matter what the original service call function returns, the promise always ends up being "undefined". Here's some code for better context:

  srvc.sendApplicantsToSR = function (applicant) {
    var applicantURL = {snip};

var promise = $http({
    headers: {
        'Content-Type': 'application/x-www-form-urlencoded'
    },
    method: 'POST',
    url: applicantURL,
    data: applicant
})
  .success(function (data) {
    return data;
  })
  .error(function (error) {
    return [];
  });

  return promise;
  };

Next, in the controller:

for (var applicant in $scope.applicants) {
            $scope.sendATSError($scope.sendApplicantsToSR($scope.applicants[applicant]), applicant);
       }

$scope.sendATSError = function (errorCheck, applicantNumber) {
      if (angular.isUndefined(errorCheck)) {
      console.log(errorCheck);
        AtsintegrationsService.applicantErrorHandling($scope.applicants[applicantNumber].dataset.atsApplicantID);
      }
    };

The issue here is that it always detects errors since every response is undefined. How can I correctly distinguish between the two returns? Appreciate any help provided! Thanks!

javascript angularjs promise

Answer 1

Answer №1

After reviewing the angular documentation, I found this example code snippet:

$http({
  method: 'GET',
  url: '/someUrl'
}).then(function successCallback(response) {
    // Asynchronous callback for when response is available
  }, function errorCallback(response) {
    // Asynchronous error handling if server returns an error
  });

Given that information, your initial code snippet should resemble this:

 srvc.sendApplicantsToSR = function(applicant) {
     var applicantURL = {
         snip
     };

     return $http({
         headers: {
             'Content-Type': 'application/x-www-form-urlencoded'
         },
         method: 'POST',
         url: applicantURL,
         data: applicant
     });
 };

Answer 2

After reviewing the angular documentation, I found this example code snippet:

$http({
  method: 'GET',
  url: '/someUrl'
}).then(function successCallback(response) {
    // Asynchronous callback for when response is available
  }, function errorCallback(response) {
    // Asynchronous error handling if server returns an error
  });

Given that information, your initial code snippet should resemble this:

 srvc.sendApplicantsToSR = function(applicant) {
     var applicantURL = {
         snip
     };

     return $http({
         headers: {
             'Content-Type': 'application/x-www-form-urlencoded'
         },
         method: 'POST',
         url: applicantURL,
         data: applicant
     });
 };

Answer 3

Answer №2

Like mentioned by others, the use of $http's .success() and .error() methods is no longer recommended in favor of using .then().

In the function .sendApplicantsToSR(), there is no need to chain .then() as you do not necessarily have to process the data or handle errors at that moment.

$scope.sendApplicantsToSR = function (applicant) {
    var applicantURL = {snip};
    return $http({
        headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
        method: 'POST',
        url: applicantURL,
        data: applicant
    });
};

When calling this function in a loop, a promise is returned which will either follow the success path or the error path based on how you set up your callback functions with .then().

To address this correctly, structure your code with $scope.sendApplicantsToSR() on the outside and $scope.sendATSError() on the inside, connected by .then().

for (var prop in $scope.applicants) {
    var applicant = $scope.applicants[prop];
    $scope.sendApplicantsToSR(applicant).then(null, $scope.sendATSError.bind(null, applicant));
}
// Use `null` for success cases and provide a function for error handling.

Passing the applicant parameter simplifies the error handler function, $scope.sendATSError():

$scope.sendATSError = function (applicant) {
    return AtsintegrationsService.applicantErrorHandling(applicant.dataset.atsApplicantID);
};

If you need to know when all promises are settled, consider addressing it separately in another question.

Answer 4

Like mentioned by others, the use of $http's .success() and .error() methods is no longer recommended in favor of using .then().

In the function .sendApplicantsToSR(), there is no need to chain .then() as you do not necessarily have to process the data or handle errors at that moment.

$scope.sendApplicantsToSR = function (applicant) {
    var applicantURL = {snip};
    return $http({
        headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
        method: 'POST',
        url: applicantURL,
        data: applicant
    });
};

When calling this function in a loop, a promise is returned which will either follow the success path or the error path based on how you set up your callback functions with .then().

To address this correctly, structure your code with $scope.sendApplicantsToSR() on the outside and $scope.sendATSError() on the inside, connected by .then().

for (var prop in $scope.applicants) {
    var applicant = $scope.applicants[prop];
    $scope.sendApplicantsToSR(applicant).then(null, $scope.sendATSError.bind(null, applicant));
}
// Use `null` for success cases and provide a function for error handling.

Passing the applicant parameter simplifies the error handler function, $scope.sendATSError():

$scope.sendATSError = function (applicant) {
    return AtsintegrationsService.applicantErrorHandling(applicant.dataset.atsApplicantID);
};

If you need to know when all promises are settled, consider addressing it separately in another question.

Answer 5

Answer №3

You should make sure to handle your promise within the controller itself.

Simply put:

.factory('myFactory', function() {
    return $http.post(...);
})
.controller('ctrl', function(){
    myFactory()
        .success(function(data){
             // manipulate your data here
        })
})

Here is a practical example:

angular.module('myApp',[])
.factory('myName', function($q, $timeout) {
    return function() {
        var deferred = $q.defer();
        $timeout(function() {
            deferred.resolve('Bar');
        }, 2000);
        return deferred.promise;
    }
})
.controller('ctrl', function($scope, myName) {
    $scope.message = 'Waiting for update.';
    myName().then(function(data) {
       $scope.message = 'Hi '+data+'!';
    });
});

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="myApp" ng-controller="ctrl">
    {{message}}!
</div>

Answer 6

You should make sure to handle your promise within the controller itself.

Simply put:

.factory('myFactory', function() {
    return $http.post(...);
})
.controller('ctrl', function(){
    myFactory()
        .success(function(data){
             // manipulate your data here
        })
})

Here is a practical example:

angular.module('myApp',[])
.factory('myName', function($q, $timeout) {
    return function() {
        var deferred = $q.defer();
        $timeout(function() {
            deferred.resolve('Bar');
        }, 2000);
        return deferred.promise;
    }
})
.controller('ctrl', function($scope, myName) {
    $scope.message = 'Waiting for update.';
    myName().then(function(data) {
       $scope.message = 'Hi '+data+'!';
    });
});

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="myApp" ng-controller="ctrl">
    {{message}}!
</div>

Angular Resolution Verification

Answer №1

Answer №2

Answer №3

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