Facebook realtime updates, no post update from facebook - facebook-graph-api

Question

I followed the guide realtime updates on facebook.
My application is a tab page.
I'm using the sandbox environment.
Initially set up by the signing of the dashboard.
The callback URL endpoint verify works fine.
I did an post on the page for only test.
But so far (after 24hrs), i received no update post from facebook.
On log apache server, there is no post from facebook too.
My callback script:
<?php
define('UPD_FILE', 'updates.log');
$method = $_SERVER['REQUEST_METHOD'];
global $log_file;
if ($method == 'GET' && $_GET['hub_mode'] == 'subscribe' && $_GET['hub_verify_token'] == 'jogabonito') {
echo $_GET['hub_challenge'];
exit;
}
else if ($method == 'POST')
{
$log_file=UPD_FILE;
$updates = json_decode(file_get_contents("php://input"), true);
logToFile("updates =".print_r($updates));
}
function logToFile($message){
global $log_file;
$hdl = fopen($log_file, 'a') or die ("couldn't open log file");
fwrite($hdl,$message."\n");
fclose($hdl);
}
?>
Grateful for the attention

Answer 1

Your code works (somewhat) fine after some requirements have been met.
You have subscribed successfully for at least one field change.
The user you are testing with has granted your app some or all of the required permissions for the fields you are subscribed for.
If one of the above isn't properly handled you won't be notified about related changes.
On another note I wrote "somewhat" because you are dumping the array content using print_r without specifying that the function should return the data rather than print it. The way you have it right now will result in a "1" result.
What you need should look more like this:
logToFile("updates =".print_r($updates, true));

Answer 2

I was facing the same problem, below solution fixed my problem,
just make an POST request to the following URL
https://graph.facebook.com/PAGE_ID/tabs?app_id=APP_ID&access_token=PAGE_ACCESS_TOKEN
Please replace the values before making a request