Close #55 add google captcha mechanism

src/User/Validator/ReCaptchaValidator.php

@@ -0,0 +1,68 @@
+<?php
+
+/*
+ * This file is part of the 2amigos/yii2-usuario project.
+ *
+ * (c) 2amigOS! <http://2amigos.us/>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Da\User\Validator;
+
+use Da\User\Component\ReCaptchaComponent;
+use Yii;
+use yii\validators\Validator;
+
+class ReCaptchaValidator extends Validator
+{
+    /**
+     * @inheritdoc
+     */
+    public $skipOnEmpty = false;
+    /**
+     * @var string the message for client validation
+     */
+    public $notCheckedMessage;
+
+    /**
+     * @inheritdoc
+     */
+    public function init()
+    {
+        parent::init();
+
+        if (null === $this->message) {
+            $this->message = Yii::t('usuario', 'The verification code is incorrect.');
+        }
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function clientValidateAttribute($model, $attribute, $view)
+    {
+        $message = addslashes(
+            $this->notCheckedMessage ?: Yii::t('usuario', '{0} cannot be blank.', $model->getAttributeLabel($attribute))
+        );
+
+        return "(function(messages){if(!grecaptcha.getResponse()){messages.push('{$message}');}})(messages);";
+    }
+
+    /**
+     * @inheritdoc
+     */
+    protected function validateValue($value)
+    {
+        if (empty($value)) {
+            if (!($value = Yii::$app->request->post('g-recaptcha-response'))) {
+                return [$this->message, []];
+            }
+        }
+        /** @var ReCaptchaComponent $recaptcha */
+        $recaptcha = Yii::$app->get('recaptcha');
+
+        return $recaptcha->verify($value) ? null : [$this->message, []];
+    }
+}