title: SwiftMailer gmail oauth refresh access token
body: <p>I would like to send emails with the gmail SMTP using oauth authentification. </p>
  
  <p>On this documentation :
  <a href="https://github.com/swiftmailer/swiftmailer/blob/b11f0054d96fa49200d10401e34d879e46c2a2c6/lib/classes/Swift/Transport/Esmtp/Auth/XOAuth2Authenticator.php" rel="nofollow">https://github.com/swiftmailer/swiftmailer/blob/b11f0054d96fa49200d10401e34d879e46c2a2c6/lib/classes/Swift/Transport/Esmtp/Auth/XOAuth2Authenticator.php</a></p>
  
  <p>I can find this sample code: </p>
  
  <pre><code>$transport = Swift_SmtpTransport::newInstance('smtp.gmail.com', 587, 'tls')
    -&gt;setAuthMode('XOAUTH2')
    -&gt;setUsername('YOUR_EMAIL_ADDRESS')
    -&gt;setPassword('YOUR_ACCESS_TOKEN');
  </code></pre>
  
  <p>Great it's work. But it's work just for 1h because the access token expire after this period. I don't find any way to get a renewal of the access token? How we can passe the refresh token to swiftmailer?</p>