Adds validation error handling

[ninjapenguin]

MultiErrorResponse - Supports error output with multiple errors
Exception\Validation - Excepts Laravel messagebag of validation fails

Models simply overload the getValidationRules to return a ruleset array (see http://laravel.com/docs/5.0/validation)

An example validation failure might look like:

{
   "errors":[
      {
         "status":400,
         "code":1040,
         "title":"Validation Fail",
         "detail":"The price must be a number.",
         "meta":{
            "field":"price"
         }
      },
      {
         "status":400,
         "code":1040,
         "title":"Validation Fail",
         "detail":"The ingredients field is required.",
         "meta":{
            "field":"ingredients"
         }
      }
   ]
}

[egeriis]

Thank you for another pull request!

I think that an improvement to this, we could utilise the Laravel 5 Form Request validation. If you're not familiar with this concept, you can read about it here: http://laravel.com/docs/5.0/validation#form-request-validation

It sets up a framework for handling validation errors. Although they name it form request validation, I believe it could be used here and provide a better structure.

There is also a video at Laracasts about this topic: https://laracasts.com/series/laravel-5-fundamentals/episodes/12

Let me know what you think.

Also keep in mind the original exception handling convention; any method can throw a EchoIt\JsonApi\Exception which should be handled by the controller.

[ninjapenguin]

Hi

Thanks for the feedback, I am actually familiar with the form validation but wasn't sure it was really suitable here - I'll have another look at it though!

With regards to the original concept, EchoIt\JsonApi\Exception\Validation extends EchoIt\JsonApi\Exception so the original catch in the ApiController will still catch that exception (based on PHP inheritance model)

Thanks very much

[egeriis]

I didn't notice that EchoIt\JsonApi\Exception\Validation was extending the Exception class. That's great. I was just taking notice of the added layer of error responding in MultiErrorResponse.
Can you elaborate on the purpose of adding this layer instead of handling all errors in the controllers?

[ninjapenguin]

Certainly, The key difference here is between ErrorResponse and MultiErrorResponse, these classes represent the encapsulation of the logic for the presenting of the exception as a JSONApi JSON response. This again extends from the Laravel JsonResponse class and so maintains the )already existing) separation of concerns within the package

Hope that helps!