How to read stream from certain user with app access token - facebook

Question

I created facebook app that is requesting aditional permissions read_stream and publish_stream.
After user accepts app and allows app to read posts when I try to get posts with fql query I get empty results.
Here is code
$appAccessToken = APP_ID|APP_SECRET
$fql = 'SELECT post_id, type, likes, source_id, created_time, privacy, comments FROM stream WHERE source_id = xxxxxxxxxxxxx';
$param = array(
'method' => 'fql.query',
'query' => $fql,
'callback' => '',
"access_token" => $appAccessToken
);
$fqlResult = $facebook->api($param);
and results are empty array
Array
(
)
I can get results for active user using user_access_token ("access_token" = $facebook->getAccessToken();) or even without access token in fql query.
The problem is that I need access to all user posts that are using app not only for active user. What would be the best way to read stream for offline users?

Answer 1

You could request a long lived access token
https://developers.facebook.com/roadmap/offline-access-removal/
but you cannot use an app access token to read a private user stream. You can only use a users access_token to read their stream as it is a user permission and so requires their access token to validate they have authenticated your app with that permission. In fact if you look at the docs for the stream table, it mentions you can only read it for the current session user (it's the sentence above the 1st 2 bullet points)
https://developers.facebook.com/docs/reference/fql/stream/
An app access token should be able to read public posts by a user though.
I'm not sure what the implications are on storing the long lived access token so you will have to do your research to make sure you don't violate any TOS.