Get ajax response inside dataTable()

Question

This is my existing code for pagination here I am getting error as roleList is not defined.
I don't know how to use ajax response inside of dataTable().What I did wrong? I got struck with this part for last 3 days,however I searched for a solution for long time,but couldn't fine one.

function empRoles() {debugger
    table = $('#mydata').DataTable({
        "ajax": {
            "type": 'POST',
            "dataType": 'json',
            "url": '/Admin/getRolesList',
            "dataSrc": function (response) {
                var roleList = response;
                console.log(roleList)
            },
            "data": {
                "json": JSON.stringify(roleList)
            }

        },
        "columns": [{
            "data": "sNo"
        }, { 
            "data": "roleName",
            "className": "roleName"
        }, {
            "data": "roleName",
            "render": (data, type, row, meta) => `
                <button class="btn edit btn-info" id="edit${row.sNo}">
                    <i class="fa fa-pencil"></i>
                    Edit
                </button>
                <button class="btn update btn-success" id="update${row.sNo}">
                    <i class="fa fa-floppy-o"></i>
                    Update
                </button>
                <button class="btn dlt btn-danger" data-toggle="modal" data-target="#confirm" id="delete${row.sNo}">
                    <i class="fa fa-trash-o"></i>
                    Delete
                </button>
            `
            ,
            "sortable": false
        }],
        "createdRow": (row, data, dataIndex) => {
            $(row).attr("id", "row" + data.sNo);
            $('td:eq(1)', row).attr("id", "name" + data.sNo);
        }
    });
}

Any advice please..

Answer 1

If I'm correctly understanding the problem, I believe the simplest solution would be to simply initialize the roleList variable outside of the options.

function empRoles() {
    var roleList = []; // or whatever the initial data value should be
    var table = $('#mydata').DataTable({ 
    // ...
       "dataSrc": function (response) {
            roleList = response;
            console.log(roleList)
        },
        "data": {
            "json": JSON.stringify(roleList)
        }
    // ...