How to set proper JSON response for POST method in RESTful API from FOSRestBundle?

Question

I am making a POST method for a RESTful API. The API is built on top of FOSRestBundle and NelmioApiDoc as you may notice. I am not able to validate when file is not uploaded or when rid parameter is missing and response with proper JSON. This is what I am doing:

/**
 * Set and upload avatar for reps.
 *
 * @param ParamFetcher $paramFetcher
 * @param Request $request
 *
 * @ApiDoc(
 *      resource = true,
 *      https = true,
 *      description = "Set and upload avatar for reps.",
 *      statusCodes = {
 *          200 = "Returned when successful",
 *          400 = "Returned when errors"
 *      }
 * )
 *
 * @RequestParam(name="rid", nullable=false, requirements="\d+", description="The ID of the representative")
 * @RequestParam(name="avatar", nullable=false, description="The avatar file")
 *
 * @return View
 */
public function postRepsAvatarAction(ParamFetcher $paramFetcher, Request $request)
{
    $view = View::create();
    $uploadedFile = $request->files;

    // this is not working I never get that error if I not upload any file
    if (empty($uploadedFile)) {
        $view->setData(array('error' => 'invalid or missing parameter'))->setStatusCode(400);
        return $view;
    }

    $em = $this->getDoctrine()->getManager();
    $entReps = $em->getRepository('PDOneBundle:Representative')->find($paramFetcher->get('rid'));

    if (!$entReps) {
        $view->setData(array('error' => 'object not found'))->setStatusCode(400);
        return $view;
    }

    .... some code

    $repsData = [];

    $view->setData($repsData)->setStatusCode(200);

    return $view;
}

If I not upload a file I got this response:

Error: Call to a member function move() on a non-object
500 Internal Server Error - FatalErrorException

But as Symfony exception error not as a JSON as I want and need, so code is never entering in the if.

If I not set rid then I got this error:

Request parameter "rid" is empty
400 Bad Request - BadRequestHttpException

But again as Symfony exception error and not as a JSON. How do I response a proper JSON if rid is not present or if file wasn't uploaded? Any advice?

Answer 1

$request->files is an instance of FileBag. Use $request->files->get('keyoffileinrequest') to get the file.

rid is specified is a required parameter, so yeah, it throws a BadRequestHttpException if you don't set it. It behaves like it should. You should try setting rid to an ID that isn't in the database, then you should see your own error message.

If you want rid to be optional you could add a default value for rid:

* @RequestParam(name="rid", nullable=false, requirements="\d+", default=0, description="The ID of the representative")

Something like that. Now rid will be zero, your Repository::find call will probably return null and your error view will be returned. But I recommend that you keep it like it is, it is proper behavior.