Laravel yajra datatable: cannot retrieve the search parameter from ajax call in controller

Question

I am trying to build a dataTable with custom filtering with the help of yajra datatable from here :

HTML table in view :

  <form id="search-form" class="form-inline" method="POST" role="form" action="#">


      <select id="batch" name="batch">
        <option value="">Select</option>
        <option value="22">Skill Level CBE Dec 2018</option>
        <option value="2">Batch 2</option>

      </select>

      <button class="btn  btn-primary" type="submit">Search</button>

  </form>

     <table class="table table-striped table-bordered datatable" cellspacing="0" width="100%">

                                    <thead>

                                        <tr>



                                            <th>{{ getPhrase('S/N')}}</th>

                                            <th>{{ getPhrase('Batch')}}</th>
                                            <th>{{ getPhrase('Course')}}</th>
                                            <th>{{ getPhrase('Subject')}}</th>

                                            <th>{{ getPhrase('title')}}</th>

                                            <th>{{ getPhrase('otq_marks')}}</th>
                                            <th>{{ getPhrase('cr_marks')}}</th>

                                            <th>{{ getPhrase('total')}}</th>
                                            <th>{{ getPhrase('average')}}</th>




                                        </tr>

                                    </thead>



         </table>


        @section('footer_scripts')



         @include('common.datatables', array('route'=>URL_STUDENT_EXAM_GETATTEMPTS.$user->slug, 'route_as_url' => 'TRUE'))


        @stop

As to common.datatables, datatables.blade.php has :

$.ajaxSetup({
    headers: {
        'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
        }
    });

     tableObj = $('.datatable').DataTable({
            processing: true,
            serverSide: true,
                retrieve :true,
            // cache: true,
            type: 'GET',

            ajax: {
             url: '{{ $routeValue }}',
             data: function (d) {
                 d.batch = $('#batch').val();

             }
         }



     });


    $('#search-form').on('submit', function(e) {
        tableObj.draw();
        e.preventDefault();
    });

ajax url value $routeValue refers to URL_STUDENT_EXAM_GETATTEMPTS constant (to be clarified later) used in view in whatever way.

When I select a value from the "batch" drop-down and press the submit button, an ajax call is made to the route. In browser inspection tool, I see that a lot of query parameters are added in the ajax URL and our batch param is also there. Now I need to retrieve that batch parameter inside the controller.

Now about the server side code :

The constant URL_STUDENT_EXAM_GETATTEMPTS used in blade has the value PREFIX.'exams/student/get-exam-attempts/'

And in route.php, the route is defined as :

Route::get('exams/student/get-exam-attempts/{user_slug}/{exam_slug?}', 'StudentQuizController@getExamAttemptsData');

In controller I have :

public function getExamAttemptsData(Request $request,$slug, $exam_slug = '')
    {

    //body goes here 

    }

I have used all the following methods to get the batch parameter in the controller but in vain :

$request->get('batch')
$request->query('batch')
Input::get('batch')

How can I retrieve the value of batch inside the controller ?

EDIT: BTW I am using use Illuminate\Http\Request; for the Request $request variable in controller function parameter

EDIT2: The browser inspection tool shows the ajax request url as :

http:// localhost/lcbs/exams/student/get-exam-attempts/myuser123 ?draw=2&columns%5B0%5D%5Bdata%5D=0......search%5Bregex%5D=false&batch=22&_=1541684388689.

So you see that batch is there in the query parameters. But inside the controller, the code $request->getQueryString() only shows %2Fexams%2Fstudent%2Fget-exam-attempts%2Fmyuser123

And \URL::current() shows http:// localhost/lcbs/exams/student/get-exam-attempts/myuser123

That means, the $request misses the complete query string.

EDIT3: @ Adrian Hernandez-Lopez, I am pasting the FULL content of Kernel.php here :

namespace App\Http;

use Illuminate\Foundation\Http\Kernel as HttpKernel;

class Kernel extends HttpKernel
{
    /**
     * The application's global HTTP middleware stack.
     *
     * These middleware are run during every request to your application.
     *
     * @var array
     */
    protected $middleware = [
        \Illuminate\Foundation\Http\Middleware\CheckForMaintenanceMode::class,

    ];

    /**
     * The application's route middleware groups.
     *
     * @var array
     */
    protected $middlewareGroups = [
        'web' => [
            \App\Http\Middleware\EncryptCookies::class,
            \Illuminate\Cookie\Middleware\AddQueuedCookiesToResponse::class,
            \Illuminate\Session\Middleware\StartSession::class,
            \Illuminate\View\Middleware\ShareErrorsFromSession::class,
            \App\Http\Middleware\VerifyCsrfToken::class,
        ],

        'api' => [
            'throttle:60,1',
        ],
    ];

    /**
     * The application's route middleware.
     *
     * These middleware may be assigned to groups or used individually.
     *
     * @var array
     */
    protected $routeMiddleware = [
        'auth' => \App\Http\Middleware\Authenticate::class,
        'auth.basic' => \Illuminate\Auth\Middleware\AuthenticateWithBasicAuth::class,
        'can' => \Illuminate\Foundation\Http\Middleware\Authorize::class,
        'guest' => \App\Http\Middleware\RedirectIfAuthenticated::class,
        'throttle' => \Illuminate\Routing\Middleware\ThrottleRequests::class,

        'role' => \Zizaco\Entrust\Middleware\EntrustRole::class,
        'permission' => \Zizaco\Entrust\Middleware\EntrustPermission::class,
        'ability' => \Zizaco\Entrust\Middleware\EntrustAbility::class,
       // 'adminOrGuest' => \App\Http\Middleware\AdminOrGuestMiddleware::class,

    ];
}

Answer 1

Looks like the ? in the Route is not used to define an optional parameter but a string instead:

Route::get('exams/student/get-exam-attempts/{user_slug}/{exam_slug?}', 'StudentQuizController@getExamAttemptsData');

Could you please change it and see what you get?

Route::get('exams/student/get-exam-attempts/{user_slug}/{exam_slug}', 'StudentQuizController@getExamAttemptsData');

Also, the query string you posted has a space after myyser123, this could also explain the issue.

http:// localhost/lcbs/exams/student/get-exam-attempts/myuser123 ?draw=2&columns%5B0%5D%5Bdata%5D=0......search%5Bregex%5D=false&batch=22&_=1541684388689.

So I would suggest to check how the value is defined in the javascript code

url: '{{ $routeValue }}',