How can i recieve pushed message from google pubsub - publish-subscribe

Question

I Have created new topic and new subscription and set delivery type: push and set end point URL :
index.php :
<?php
print_r($_POST);
$data = json_encode($_POST);
print_R($data);
$fp = fopen('data.txt', 'a+');
fwrite($fp, $data);
fclose($fp);
?>
When publish message i want to process the data from this end point as an example save data to file.
the file is created but with empty array [].
any issue in my php code, does the data store in $_POST or i need to use another way.

Answer 1

To fetch Pub/Sub messages, you need to use the Google Pub/Sub library. Given that you've set your subscription endpoint to your URL, the code should look like something similar to this:
use Google\Cloud\PubSub\PubSubClient;
$projectId = "YOUR-PROJECT-ID";
$subscriptionName = "YOUR-SUBSCRIPTION-NAME";
$pubsub = new PubSubClient([
'projectId' => $projectId,
]);
$subscription = $pubsub->subscription($subscriptionName);
$pullMessages = [];
foreach ($subscription->pull(['returnImmediately' => true]) as $pullMessage) {
$pullMessages[] = $pullMessage;
$msg = $pullMessage->data();
$fp = fopen('data.txt', 'a+');
fwrite($fp, $msg);
fclose($fp);
}
// acknowledge PULL messages
if ($pullMessages) {
$subscription->acknowledgeBatch($pullMessages);
}
You can find an example here. As well as a more in-detail explanation here.