Adds validation error handling

src/EchoIt/JsonApi/Exception/Validation.php

@@ -0,0 +1,42 @@
+<?php namespace EchoIt\JsonApi\Exception;
+
+use EchoIt\JsonApi\Exception;
+use EchoIt\JsonApi\MultiErrorResponse;
+use Illuminate\Support\MessageBag as ValidationMessages;
+
+/**
+ * Validation represents an Exception that can be thrown in the event of a validation failure where a JSON response may be expected.
+ *
+ * @author Matt <matt@ninjapenguin.co.uk>
+ */
+class Validation extends Exception
+{
+    protected $httpStatusCode;
+    protected $validationMessages;
+
+    /**
+     * Constructor.
+     *
+     * @param string                        $message        The Exception message to throw
+     * @param int                           $code           The Exception code
+     * @param int                           $httpStatusCode HTTP status code which can be used for broken request
+     * @param Illuminate\Support\MessageBag $messages       Validation errors
+     */
+    public function __construct($message = '', $code = 0, $httpStatusCode = 500, ValidationMessages $messages = NULL)
+    {
+        parent::__construct($message, $code);
+
+        $this->httpStatusCode = $httpStatusCode;
+        $this->validationMessages = $messages;
+    }
+
+    /**
+     * This method returns a HTTP response representation of the Exception
+     *
+     * @return JsonApi\MultiErrorResponse
+     */
+    public function response()
+    {
+        return new MultiErrorResponse($this->httpStatusCode, $this->code, $this->message, $this->validationMessages);
+    }
+}

src/EchoIt/JsonApi/Handler.php

@@ -526,6 +526,33 @@ protected function handleGetDefault(Request $request, $model)
         return $results;
     }
 
+    /**
+     * Validates passed data against a model
+     * Validation performed safely and only if model provides rules
+     *
+     * @param  EchoIt\JsonApi\Model $model  model to validate against
+     * @param  Array                $values passed array of values
+     *
+     * @throws Exception\Validation         Exception thrown when validation fails
+     *
+     * @return Bool                         true if validation successful
+     */
+    protected function validateModelData(Model $model, Array $values)
+    {
+        $validationResponse = $model->validateArray($values);
+
+        if ($validationResponse === true) {
+            return true;
+        }
+
+        throw new Exception\Validation(
+            'Bad Request',
+            static::ERROR_SCOPE | static::ERROR_HTTP_METHOD_NOT_ALLOWED,
+            BaseResponse::HTTP_BAD_REQUEST,
+            $validationResponse
+        );
+    }
+
     /**
      * Default handling of POST request.
      * Must be called explicitly in handlePost function.
@@ -537,6 +564,8 @@ protected function handleGetDefault(Request $request, $model)
     public function handlePostDefault(Request $request, $model)
     {
         $values = $this->parseRequestContent($request->content, $model->getResourceType());
+        $this->validateModelData($model, $values);
+
         $model->fill($values);
 
         if (!$model->save()) {

src/EchoIt/JsonApi/Model.php

@@ -1,5 +1,6 @@
 <?php namespace EchoIt\JsonApi;
 
+use Validator;
 use Illuminate\Database\Eloquent\Collection;
 use Illuminate\Database\Eloquent\Model as BaseModel;
 use Illuminate\Database\Eloquent\Relations\Pivot as Pivot;
@@ -121,6 +122,37 @@ public function getResourceType()
         return ($this->resourceType ?: $this->getTable());
     }
 
+    /**
+     * Validate passed values
+     *
+     * @param  Array  $values  user passed values (request data)
+     *
+     * @return bool|Illuminate\Support\MessageBag  True on pass, MessageBag of errors on fail
+     */
+    public function validateArray(Array $values)
+    {
+        if (count($this->getValidationRules())) {
+            $validator = Validator::make($values, $this->getValidationRules());
+
+            if ($validator->fails()) {
+                return $validator->errors();
+            }
+        }
+
+        return True;
+    }
+
+    /**
+     * Return model validation rules
+     * Models should overload this to provide their validation rules
+     *
+     * @return Array validation rules
+     */
+    public function getValidationRules()
+    {
+        return [];
+    }
+
     /**
      * Convert the model instance to an array. This method overrides that of
      * Eloquent to prevent relations to be serialize into output array.

src/EchoIt/JsonApi/MultiErrorResponse.php

@@ -0,0 +1,39 @@
+<?php namespace EchoIt\JsonApi;
+
+use Illuminate\Http\JsonResponse;
+use Illuminate\Support\MessageBag as ValidationMessages;
+
+/**
+ * MultiErrorResponse represents a HTTP error response containing multiple errors with a JSON API compliant payload.
+ *
+ * @author Matt <matt@ninjapenguin.co.uk>
+ */
+class MultiErrorResponse extends JsonResponse
+{
+    /**
+     * Constructor.
+     *
+     * @param int                           $httpStatusCode   HTTP status code
+     * @param mixed                         $errorCode        Internal error code
+     * @param string                        $errorTitle       Error description
+     * @param Illuminate\Support\MessageBag $errors           Validation errors
+     */
+    public function __construct($httpStatusCode, $errorCode, $errorTitle, ValidationMessages $errors = NULL)
+    {
+        $data = [ 'errors' => [] ];
+
+        if ($errors) {
+            foreach ($errors->keys() as $field) {
+
+                foreach ($errors->get($field) as $message) {
+
+                    $data['errors'][] = [ 'status' => $httpStatusCode, 'code' => $errorCode, 'title' =>  'Validation Fail', 'detail' => $message, 'meta' => ['field' => $field] ];
+
+                }
+
+            }
+        }
+
+        parent::__construct($data, $httpStatusCode);
+    }
+}