Connect to Google drive API without user interaction using PHP - php

Question

I want to upload files to Google Drive using the API, but I need to do this using a cron job (autobackup of webfiles+sql to Google drive).
That means (I suppose) that I need to authenticate using something else than the user interaction method.
The example that I have been using: https://developers.google.com/api-client-library/php/auth/web-app to get me going, and its working with user authenticating.
I would appreciate some tips on how to do this without user interaction, so it can run on a cronjob.
Here are the PHP code for authenticate and upload file (working example with manual user auth and single file upload)
<?php
require_once 'google-api-php-client/vendor/autoload.php';
/* Config */
$servername = 'content here';
$redirect_uri = 'https://example.com/';
$client = new Google_Client();
$client->setAuthConfig('client_manual_authentiation.json');
$client->addScope(Google_Service_Drive::DRIVE);
if(isset($_SESSION['access_token']) && $_SESSION['access_token']) {
$client->setAccessToken($_SESSION['access_token']);
$drive = new Google_Service_Drive($client);
foreach($drive->files->listFiles(array("q" => "name = '{$servername}'"))->getFiles() as $key => $element){
if($element->name == $servername){
//create todays folder on Google Drive
$today_folder_meta = new Google_Service_Drive_DriveFile(array(
'name' => 'myfile.txt',
'mimeType' => 'application/vnd.google-apps.folder',
'parents' => array($element['id'])
));
$today_folder = $drive->files->create($today_folder_meta, array(
'fields' => 'id'
));
}
}
}else{
if (!isset($_GET['code'])) {
$auth_url = $client->createAuthUrl();
header('Location: ' . filter_var($auth_url, FILTER_SANITIZE_URL));
} else {
$client->authenticate($_GET['code']);
$_SESSION['access_token'] = $client->getAccessToken();
header('Location: ' . filter_var($redirect_uri, FILTER_SANITIZE_URL));
}
}
?>

Answer 1

To do this, you want to create a Google OAuth2 Service Account. You can then download a set of JSON credentials that your app will use to authenticate without user interaction.
This is described in the following article:
Using OAuth 2.0 for Server to Server Applications
https://developers.google.com/identity/protocols/OAuth2ServiceAccount
You will then be able to download credentials like the following to use in your app:
{
"type":"service_account",
"project_id":"your-project-id",
"private_key_id":"deadbeefdeadbeefdeadbeefdeadbeefdeadbeef",
"private_key":"-----BEGIN PRIVATE KEY-----\nMIIEv...4XIk=\n-----END PRIVATE KEY-----\n",
"client_email":"foobar#bazqux.iam.gserviceaccount.com",
"client_id":"12345678901234567890",
"auth_uri":"https://accounts.google.com/o/oauth2/auth",
"token_uri":"https://accounts.google.com/o/oauth2/token",
"auth_provider_x509_cert_url":"https://www.googleapis.com/oauth2/v1/certs",
"client_x509_cert_url":"https://www.googleapis.com/robot/v1/metadata/x509/foobar%40bazqux.iam.gserviceaccount.com"
}
Here is a Google PHP example of how to use this:
https://github.com/google/google-api-php-client/blob/master/examples/service-account.php
You can create the Service Account in the Google API Console as shown here: