如何在指定时间（计划任务）后调用 Angular js 中的 api 端点？

Question

i have the following service that get some data from an API and it works fine

i call this service in the app.run() method

// some code...

$scope.pageStudents;

    $scope.getStudentsPage = function(){

        $http({
              method: 'GET',
              url: 'studentsResource/students'
            }).then(function successCallback(response) {

                $scope.pageStudents = response.data;

              });

    };


    //i want to call this method every 5 min for example.
    $scope.getStudentsPage();

my issue is how i can call my $scope.getStudentsPage(); after each 5 min , something like scheduled job (like quartz in java) , is angular or javascript support this concept ? please anyone can guide me on how to achieve this operation. thanks in advance.

Answer 1

If you want to take a delayed action once, then you can use angular's $timeout service. If you want it to happen multiple times, there's the $interval service.

So like this:

$scope.pageStudents;

$scope.getStudentsPage = function(){
    $http({
        method: 'GET',
        url: 'studentsResource/students'
    }).then(function successCallback(response) {
        $scope.pageStudents = response.data;
    });
};

$interval(function () {
    $scope.getStudentsPage();
}, 300000); // <--- 5 minutes in milliseconds

In plain javascript, you would use window.setTimeout or window.setInterval to do this. In angularjs you should instead use the $timeout and $interval services, because angularjs won't be able to run its change detection correctly otherwise.

Documentation for $timeout and $interval can be found here:
https://docs.angularjs.org/api/ng/service/$timeout
https://docs.angularjs.org/api/ng/service/$interval

And for setTimeout and setInterval here:
https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setTimeout
https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setInterval