Laravel Datatable with json data

Prepare the view with table and javascript

var fx_currency = $('#fx_currency_table').DataTable({
       processing: true,
       serverSide: true,
       bPaginate: true,
       buttons:[],
       ajax: '/fxcurrency',
       columnDefs: [ {
         "targets": 4,
         "orderable": false,
         "searchable": false
         } ]
 });

<div class="card-body">
  <table class="table table-border table-striped" id="fx_currency_table" width="100%>
    <thread>
      <tr>
        <th>Currency Code</th>
        <th>DSP</th>
        <th>Bid</th>
        <th>Ask</th>
        <th>@lang('message.action')</th>
      </tr>
    </thread>
  </table>
</div>

Laravel Controller

 public function index()
     {
         if (!auth()->user()->can('user.view') && !auth()->user()->can('user.create')) {
             abort(403, 'Unauthorized action.');
         }         

         if (request()->ajax()) {
           $business_id = request()->session()->get('user.business_id');
           $fxcurrency = FxCurrency::where('business_id', $business_id)
                       ->select(['currency_code', 'id', 'dsp', 'ask', 'bid']);
 
             return Datatables::of($fxcurrency)
                 ->addColumn(
                     'action',
                     '
                     <button data-href="{{action(\'FxCurrencyController@edit\', [$id])}}" class="btn btn-xs btn-info btn-modal" data-container=".fxcurrency_edit_modal"><i class="fas fa-edit"></i> Edit</button>
                     &nbsp;
    <button data-href="{{action(\'FxCurrencyController@destroy\', [$id])}}" class="btn btn-xs btn-modal btn-info delete_user_button" data-container=".location_edit_modal"><i class="fas fa-trash-alt"></i> Delete</button>
                    ‘
                 )
                 ->removeColumn('id')
                 ->rawColumns([4])
                 ->editColumn('ask', function($fxcurrency) {
                   return $this->util->pack_dsp($fxcurrency->ask, $fxcurrency->dsp);
                 })
                 ->editColumn('bid', function($fxcurrency) {
                   return $this->util->pack_dsp($fxcurrency->bid, $fxcurrency->dsp);
                 })
                 ->make(false)
                 ;
         }
         return view('fx_currency.index');
     }