How to set up Google Drive push notifications for a file, and test if they work by catching them and writing them in a file with a PHP script.

A Google Drive push notifications.md

Activate notifications for the file with ID [file-id] by posting some JSON to this URL: https://www.googleapis.com/drive/v3/files/[file-id]/watch Authorization: Bearer auth_token_for_current_user Content-Type: application/json

Minimal JSON you need to POST:

{
  "id": "[some unique ID for your push, you can define it yourself but it mus be unique]",
  "type": "web_hook",
  "address": "https://www.example.com/catch.php"
}

The answer if all goes well:

{
    "kind": "api#channel",
    "id": "[some unique ID for your push, you can define it yourself but it must be unique]",
    "resourceId": "[resourceId]",
    "resourceUri": "https://www.googleapis.com/drive/v3/files/[file-id]?acknowledgeAbuse=false&supportsTeamDrives=false&alt=json",
    "expiration": "1526248563000"
}

Note:

• The push notifications will only work for one hour and need to be re-activated after that.
• If you enable notifications for a folder, only the changes for its direct children are shown, not the changes inside the child-folders.

If you set the notifications, you might also need a new oAuth token. If you set the access-type of your app to offline, you can get one using your refresh-token.

Post to this URL: https://accounts.google.com/o/oauth2/token

Post these variables as x-www-urlencoded:

• client_id
• client_secret
• refresh_token
• grant_type = refresh_token

More info: https://developers.google.com/drive/v3/web/push

catch.php

<?php
// Catch any request and write it to a file

class DumpHTTPRequestToFile {

	public function execute($targetFile) {

		$data = sprintf(
			"%s %s %s\n\nHTTP headers:\n",
			$_SERVER['REQUEST_METHOD'],
			$_SERVER['REQUEST_URI'],
			$_SERVER['SERVER_PROTOCOL']
		);

		foreach ($_SERVER as $name => $value) {
			$data .= $name . ': ' . $value . "\n";
		}

		$data .= "\nRequest body:\n";

		file_put_contents(
			$targetFile,
			$data . file_get_contents('php://input') . "\n\n\n\n",
			FILE_APPEND
		);

		echo("Done!\n\n");
	}
}


(new DumpHTTPRequestToFile)->execute('dump.txt');

Beginner question I know? Where do I find or generate the auth_token_for_current_user?