Ajax调用不并行

Question

i have two ajax calls. the first call is for read a file and save it into the DB (mysql) and at the bottom of a for loop they set an session variable of the "status" like the interval. The second call return the session variable.

this is my javascript code:

 var interval = null;
function test(data) {
    var i = 0;
    interval = setInterval(function () {
        $.ajax({
            url: '/admin/movies/progress',
            type: "GET",
            async: true,
            dataType: "text",
            success: function (data) {
                console.log(data);
                $('#saveFileProgressBar').width(data[0]);
            },
            error: function (XMLHttpRequest, textStatus, errorThrown) {
                toastr.error('error progressbar', 'Download File');
            }
        });
        i++;
        if(i == 5){
            clearInterval(interval);
        }
    }, 500);

    $.ajax({
        url: '/admin/movies/1',
        type: "GET",
        async: true,
        dataType: "text",
        success: function (data) {
            console.log(data);

        },
        error: function (XMLHttpRequest, textStatus, errorThrown) {
            toastr.error('error', 'Download File');
        }
    });
}

this is my laravel 5.4 code:

// Mapped to mysite.com/admin/movies/progress
public function getProgress() {   
    return Response::json(array(Session::get('progress')));
}

// Mapped to mysite.com/admin/movies/1
public function postGenerate() {
    // getting values from form (like $record_num)
    Session::put('progress', 0);
    Session::save(); // Remember to call save()

    for ($i = 1; $i < 100; $i++) {
        sleep(1);
        Session::put('progress', $i);
        Session::save(); // Remember to call save()
    }

    return "done";
}

///////EDIT///////

my new PHP code:

public function getProgress() {
    $rawData = file_get_contents('plugins/elFinder-2.1.25/files/data/progressFile.json');
    $cacheData = json_decode($rawData, true);
    return $cacheData;
}

public function postGenerate() {
    // getting values from form (like $record_num)
    for ($i = 0; $i < 10; $i++) {
        $data['progress'] = $i;
        $fres = fopen('plugins/elFinder-2.1.25/files/data/progressFile.json', 'w');
        fwrite($fres, json_encode($data));
        fclose($fres);
        sleep(1);
    }
    return "true";
}

my javascript code:

 var interval = null;
function test() {
    var i = 0;
    interval = setInterval(function () {
        $.ajax({
            url: '/admin/movies/progress',
            type: "GET",
            async: true,
            dataType: "text",
            success: function (data) {
                console.log(data);
                $('#saveFileProgressBar').width(data.progress);
            },
            error: function (XMLHttpRequest, textStatus, errorThrown) {
                toastr.error('Es ist ein Fehler aufgetreten beim Auslesen der Datei', 'Download File');
            }
        });
        i++;
        if(i == 5){
            clearInterval(interval);
        }
    }, 500);

    $.ajax({
        url: '/admin/movies/1',
        type: "GET",
        async: true,
        dataType: "text",
        success: function (data) {
            console.log(data);

        },
        error: function (XMLHttpRequest, textStatus, errorThrown) {
            toastr.error('Es ist ein Fehler aufgetreten beim Auslesen der Datei', 'Download File');
        }
    });
}

Answer 1

Instead of using session use regular file. Session files are locked for each unique session until the script is finished. so It cant be ran parallel. What you can do is store the data in plain file and access it.

To read out from the cached file

 $rawData = file_get_contents('data/progressFile.json');
 $cacheData = json_decode($rawData, true);

write like

$data['progress'] = 100;
        $fres = fopen('data/progressFile.json', 'w');
        fwrite($fres, json_encode($data));
        fclose($fres)

You can use json data structure for all the session and parse to get particular progress data or you may use separate file for ech progress data. if you are using one large file you may need to use flock() to lock the file during the writing.