Facebook PHP SDK: getting “long-lived” access token now that “offline_access” is deprecated

Question

BASIC PROBLEM: I want my app to be able to make calls to the Facebook graph api about authorized users even while the user is away.

For example, I want

Answer 1

Actually newly created apps only get a 60 day access token automatically if you are using a server side call. If you are using the client-side endpoint as shown above in the question, even new apps will still receive a short-term token initially. see: https://developers.facebook.com/docs/roadmap/completed-changes/offline-access-removal/

I had the same HTTP/1.1 400 Bad Request error that you had when using the New Endpoint and the problem was if you copy the code Facebook gives you exactly and paste it into your app, there are actually spaces in between the params, meaning there's unnecessary spaces in the url and it won't get called correctly when passed into file_get_contents() even though it works okay when pasted in the browser. This took me way too long to figure out. Hope this helps somebody! Here is my complete working code to get the extended access token out of the new endpoint (replace x's with your values):

$extend_url = "https://graph.facebook.com/oauth/access_token?client_id=xxxxxxxxxxxx&client_secret=xxxxxxxxxxxxxxxxxxxxxx&grant_type=fb_exchange_token&fb_exchange_token=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";

$resp = file_get_contents($extend_url);

parse_str($resp,$output);

$extended_token = $output['access_token'];

echo $extended_token;