Add captcha server side valdation to contact.php script

contact.php

@@ -1,4 +1,22 @@
 <?php
+function verifyCaptcha(){
+    $url = 'https://www.google.com/recaptcha/api/siteverify';
+    $data = array(
+        'secret' => '6LeLxy4UAAAAABClplWLJUjZ1_nhX_-SI7CuNcm8',
+        'response' => $_POST["g-recaptcha-response"]
+    );
+    $options = array(
+        'http' => array (
+            'header' => 'Content-Type: application/x-www-form-urlencoded\r\n',
+            'method' => 'POST',
+            'content' => http_build_query($data)
+        )
+    );
+    $context  = stream_context_create($options);
+    $verify = file_get_contents($url, false, $context);
+    $captcha_success=json_decode($verify);
+    return $captcha_success;
+}
 // process.php
 
 $errors         = array();      // array to hold validation errors
@@ -16,6 +34,13 @@ $data           = array();      // array to pass back data
     if (empty($_POST['mensage']))
         $errors['mensage'] = 'Mensaje is required.';
 
+    if(empty($_POST['g-recaptcha-response'])){
+        $errors['recaptcha'] = 'Debe validar el captcha';
+    }
+    else if(!verifyCaptcha()){
+        $errors['recaptcha'] = 'Error en la validación de ReCaptcha';
+    }
+
 // return a response ===========================================================
 
     // if there are any errors in our errors array, return a success boolean of false
@@ -48,4 +73,4 @@ $data           = array();      // array to pass back data
     // return all our data to an AJAX call
     echo json_encode($data);
 
-?>
+?>