title: Refreshing facebook long lived access token without user interaction
body: <p>My each user generating a long lived (60 days) access token from my site using graph api.But the problem is when it expires after 60 days, user have to generate it again by coming to my website.Sometimes they forget about token expiration and facebook page feed shows error in their websites.</p>
  
  <p>in another post i mentioned about how i generate token long ago here-  <code>http://stackoverflow.com/questions/16962486/extending-valid-expired-60-days-access-token-without-user-interaction</code></p>
  
  <p>Now how do i automatically refresh the long-lived token from code in their site so that user don't need to get token 2nd time by coming to my token generation website page.</p>
  
  <p>in section <code>Generating Long-Lived User Tokens from Server-Side Long-Lived Tokens</code> of facebook help page - <a href="https://developers.facebook.com/docs/facebook-login/access-tokens" rel="noreferrer">https://developers.facebook.com/docs/facebook-login/access-tokens</a> 
  I see ways to refresh token, but is it the way i want that there will be no user interaction while generating token?? I need example codes as it's hard to understand.</p>