Wordpress + Mailgun

README.md

Wordpress + Mailgun

This is a simple snippet to create a wordpress contact form that sends email using mailgun api.

Installation

. Install the mailgun plugin for wordrpess https://wordpress.org/plugins/mailgun/

. Add the config constants to your wp-config.php

. In the worpess admin, create a page and a template for that page, see page-contact.php (https://codex.wordpress.org/Template_Hierarchy)

. Add the functions to send the email csrf, json_result, contact_email.

That's pretty much it.

Improvements to be made:

• return actual http status: The way it is right now, all messages will return http status 200, although the json status field will be 500 when errors occur.

• return correct http status: The way it is right now, the error messages are all 500 instad of the correct ones.

• handle the ajax error the way it is right now, it is not handling the ajax errors.

functions.php

<?php

// ...

function csrf()
{
  if (!isset($_SESSION['token'])) {
    $token = md5(uniqid(rand(), TRUE));
    $_SESSION['token'] = $token;
  } else {
    $token = $_SESSION['token'];
  }

  return $token;
}

function json_result($message, $status = 200) 
{
  $result = array('status' => $status, 'message' => $message);

  return json_encode($result);
}


function contact_email()
{ 
  if(!class_exists('Mailgun')) {
    echo json_result('Install mailgun plugin.', 500);
    die;
  }

  $token = (isset($_POST['_token'])) ? $_POST['_token'] : null;
  $name = (isset($_POST['name'])) ? $_POST['name'] : null;
  $email = (isset($_POST['email'])) ? $_POST['email'] : null;
  $message = (isset($_POST['message'])) ? $_POST['message'] : null;


  $validToken = ($token !== null && isset($_SESSION['token']) && $_SESSION['token'] === $token);
  
  if (!$validToken) {
    echo json_result('Reload the page, invalid token.', 500);
    die;
  }

  if (empty($name) || empty($email) || empty($message)) {
    echo json_result('Please fill all the fields.', 500);
    die;
  }

  if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
    echo json_result('Invalid email address.', 500);
    die;
  }

  $mailgun = new Mailgun();
  $uri = MAILGUN_DOMAIN . '/messages';

  // email html
  $text = sprintf('<p><strong>Name</strong>:%s (%s)</p><p>%s</p>', $name, $email, $message);

  $params = array(
    'from' => sprintf('%s <%s>', $name, $email),
    'to' => CONTACT_MAIL,
    'subject' => 'Contact',
    'html' => $text,
  );

  unset($_SESSION['token']);
  $result = $mailgun->api_call($uri, $params);
  echo json_result('Email sent successfully.', 200);
  die;
}
add_action('wp_ajax_contactEmail', 'contact_email');
add_action('wp_ajax_nopriv_contactEmail', 'contact_email');

// ...

page-contact.php

<?php
/**
 * The template for displaying the contact page.
 *
 * @link https://codex.wordpress.org/Template_Hierarchy
 *
 */
while ( have_posts() ) : the_post(); ?>


<div>
  
  <article id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
  
  <h1><?php the_title( '<h1 class="entry-title">', '</h1>' ); ?></h1>
  
  <div class="entry-content">
    <?php the_content(); ?>
  </div>
  
  <div class="entry-content">

    <div id="alert" role="alert"></div>
  
    <form class="contact-form" action="/wp-admin/admin-ajax.php" method="post">
      <input type="hidden" name="action" value="contactEmail" />
      <input type="hidden" name="_token" value="<?php echo csrf() ?>" />
      <div class="form-group">
        <label for="name">Name</label>
        <input type="text" class="form-control" id="name" name="name"  placeholder="Name">
      </div>

      <div class="form-group">
        <label for="email">Email</label>
        <input type="text" class="form-control" id="email" name="email"  placeholder="Email">
      </div>
      
      <div class="form-group">

        <label for="message">Message</label>
        <textarea class="form-control" name="message" placeholder="Message"> </textarea>
      </div>
      
      <div class="form-group">
        <div class="g-recaptcha" data-sitekey="xyz"></div>
      </div>
      
      <div class="form-group">
        <button type="submit" class="btn btn-default">Send</button>
      </div>
       
    </form>

  </div><!-- .entry-content -->

</article><!-- #post-## -->   
</div>


<?php endwhile; // End of the loop. ?>

<script src='https://www.google.com/recaptcha/api.js'></script>

<script type="text/javascript">
$(document).ready(function() {

  $('.contact-form').submit(function(e) {
    e.preventDefault();



    var data = $('.contact-form').serialize();
    var $alert = $('#alert');

    var captchResponse = $('#g-recaptcha-response').val();
    if (captchResponse.length == 0 ){
      $alert.text('Please fill all the fields').removeClass().addClass('alert alert-danger');
      return;
    }

      
    $.ajax({
      type: 'POST',
      url: '/wp-admin/admin-ajax.php',
      data: data,
      success: function( data ) {
        var response = jQuery.parseJSON(data);
        
        if (response.status != 200) {
          $alert.text(response.message).removeClass().addClass('alert alert-danger');
          return;
        }
        
        $alert.text(response.message).removeClass().addClass('alert alert-success');
      }
    });
      return false;
  });
});
</script>

wp-config.php

<?php

// ...

// mailgun plugin configuration.
define( 'MAILGUN_USEAPI', true);
define( 'MAILGUN_APIKEY', 'xyz');
define( 'MAILGUN_DOMAIN', 'your-domain.com');
define( 'MAILGUN_USERNAME', 'postmaster@your-domain.com');
define( 'MAILGUN_PASSWORD', '123456');
define( 'MAILGUN_SECURE', true);
define( 'MAILGUN_FROM_NAME', 'YOUR SITE NAME');
define( 'MAILGUN_FROM_ADDRESS', 'postmaster@your-domain.com');

define( 'CONTACT_MAIL', 'destination@email.com');

//...