How can I make Laravel return a custom error for a JSON REST API

go to your app/start/global.php.

This will convert all errors for 401 and 404 to a custom json error instead of the Whoops stacktrace. Add this:

App::error(function(Exception $exception, $code){    Log::error($exception);    $message = $exception->getMessage();    // switch statements provided in case you need to add    // additional logic for specific error code.    switch ($code) {        case 401:            return Response::json(array(                    'code'      =>  401,                    'message'   =>  $message                ), 401);        case 404:            $message            = (!$message ? $message = 'the requested resource was not found' : $message);            return Response::json(array(                    'code'      =>  404,                    'message'   =>  $message                ), 404);            }});

This is one of many options to handle this errors.

Making an API it is best to create your own helper like Responser::error(400, 'damn') that extends the Response class.

Somewhat like:

public static function error($code = 400, $message = null){    // check if $message is object and transforms it into an array    if (is_object($message)) { $message = $message->toArray(); }    switch ($code) {        default:            $code_message = 'error_occured';            break;    }    $data = array(            'code'      => $code,            'message'   => $code_message,            'data'      => $message        );    // return an error    return Response::json($data, $code);}

You can pass an array to the returned JSON response:

$returnData = array(    'status' => 'error',    'message' => 'An error occurred!');return Response::json($returnData, 500);

Here is what I use (Laravel 5.2):

According to: https://laravel.com/docs/5.2/errors , we can specify a custom render function for errors in app\Exceptions\Handler.php. All I did was to change my render function to this:

    /**     * Render an exception into an HTTP response.     * Updated to return json for a request that wantsJson      * i.e: specifies      *      Accept: application/json     * in its header     *     * @param  \Illuminate\Http\Request  $request     * @param  \Exception  $e     * @return \Illuminate\Http\Response     */    public function render($request, Exception $e)    {        if ($request->ajax() || $request->wantsJson()) {            return response()->json(                          $this->getJsonMessage($e),                           $this->getExceptionHTTPStatusCode($e)                        );        }        return parent::render($request, $e);    }    protected function getJsonMessage($e){        // You may add in the code, but it's duplication        return [                  'status' => 'false',                  'message' => $e->getMessage()               ];    }    protected function getExceptionHTTPStatusCode($e){        // Not all Exceptions have a http status code        // We will give Error 500 if none found        return method_exists($e, 'getStatusCode') ?                          $e->getStatusCode() : 500;    }

After this, all you need do is make sure all your API requests specify the Accept: application/json header. Hope this helps :)