RESTful API response in Laravel 5

Question

I'm building RESTful API with Laravel. My API always returns JSON. What I would like to do, is keeping response logic at one place. Here's how I do it right now in API controller, which is pointed to by Route::controller(). Funny and ultra-useful example coming:

public function getDouble($number) {
    try {
        if (!is_numeric($number)) {
            throw new HttpException(400, 'Invalid number.');
        }

        $response = $number * 2;
        $status = 200;
    }
    catch (HttpException $exception) {
        $response = $exception->getMessage();
        $status   = $exception->getStatusCode();
    }

    return response()->json($response, $status);
}

In this example, my API route would be for example /double/13 accessed by GET method. The problem is that I repeat this try ... catch block in each method. I would like my API methods to be like:

public function getDouble($number) {
    if (!is_numeric($number)) {
        throw new HttpException(400, 'Invalid number.');
    }

    return $number;
}

And then, catch those exceptions and form JSON in another place. What is the best approach here in terms of good application architecture?

Answer 1

Response on Exception

You could do this by handling the exception in App\Exceptions\Handler.

You could do it in the render method, likeso :

/**
 * Render an exception into an HTTP response.
 *
 * @param  \Illuminate\Http\Request  $request
 * @param  \Exception  $e
 * @return \Illuminate\Http\Response
 */
public function render($request, Exception $e)
{
    if($e instanceof HttpException) {
        return response()->json($e->getMessage(), $e->getStatusCode());
    }

    return parent::render($request, $e);
}

Success Response

There are several ways to do this but I guess Middleware would be the best suited one right.

• Create a middleware (say, ApiResponseFormatterMiddleware)
• In your 'App\Http\Kernel', add it to $routeMiddleware array.
• Apply it to the api routes, response to which you want to parse.

You could do something in the lines of :

/**
 * Handle an incoming request.
 *
 * @param  \Illuminate\Http\Request  $request
 * @param  \Closure  $next
 * @return mixed
 */
public function handle($request, Closure $next)
{
    $response = $next($request);

    return response()->json($response->getOriginalContent());
}

Ofcourse, you need to change a bit of logic to parse the content the way you want it, but skeleton remains the same.