Exchange Access Token does not return output sometime in facebook graph api

Question

I am using graph api to exchange access token in one of my application, but sometime its returns blank output.

I am using this code snipet

$graph_url      = "https://graph.facebook.com/oauth/access_token?client_id=" .$app_id."&client_secret=" .$app_secret."&grant_type=fb_exchange_token&fb_exchange_token=".$user_access_token;
            $response       = @file_get_contents($graph_url);
            $response_arr   = explode('&',$response);

            $exchanged_user_access_token = explode('=',$response_arr[0]);
            return $exchanged_user_access_token[1];

It will return black response sometime

Any help will appreciate.

Thank you

Answer 1

Yes, you can solve this issue. Use the following code

<?php
$graph_url      = "https://graph.facebook.com/oauth/access_token?client_id=" .$app_id."&client_secret=" .$app_secret."&grant_type=fb_exchange_token&fb_exchange_token=".$user_access_token;
$response       = @file_get_contents($graph_url);
parse_str($response,$output);
$extended_access_token = $output['access_token'];
?>

I hope that this will help you