Create google calendar events with php and service account - authenticate issue - php

Question

Is it possible to access google calendar service while using service-account-method?
Google says indirectly, it is not possible, because calendar-service is not on the list of supported services in the documentation of service-account-method, but I personally think, it IS possible.
But how?
I am writing a calendar application in php, and there I want to create calendar events into my google-calendar without user-action (e.g. login).
I learned, that first the application has to authenticate itself against google server, using the service-account-method with a key-file .p12
I am using the following code for authentication:
(downloaded fom here: http://code.google.com/p/google-api-php-client/source/browse/trunk/examples/prediction/serviceAccount.php )
session_start();
require_once 'google-api/src/Google_Client.php';
require_once 'google-api/src/contrib/Google_CalendarService.php';
require_once 'google-api/src/contrib/Google_PredictionService.php';
$client = new Google_Client();
$client->setApplicationName(GOOGLE_APPLICATION_NAME);
$client->setClientId(GOOGLE_CLIENT_ID);
$keyfile = file_get_contents(GOOGLE_KEY_FILE);
$client->setAssertionCredentials(new Google_AssertionCredentials(
GOOGLE_SERVICE_ACCOUNT_NAME,
array('https://www.googleapis.com/auth/prediction'),
$keyfile)
);
But this login seems not to work.
How do I find out, if server is logged in at that moment?
I want to continue with this:
$cal = new Google_CalendarService($client);
if (isset($_SESSION['token'])) {
$client->setAccessToken($_SESSION['token']);
}
if ($client->getAccessToken()) {
$calList = $cal->calendarList->listCalendarList(); // <- this is line 55
print "<h1>Calendar List</h1><pre>" . print_r($calList, true) . "</pre>";
$_SESSION['token'] = $client->getAccessToken();
} else {
$authUrl = $client->createAuthUrl();
print "<a class='login' href='$authUrl'>Connect Me!</a>";
}
But in line 55 there comes this error:
Fatal error: Uncaught exception 'Google_ServiceException' with message
'Error calling GET
https://www.googleapis.com/calendar/v3/users/me/calendarList: (403)
Insufficient Permission' in
/usr/www/users/leuchtk/html/google-api/src/io/Google_REST.php:66
Stack trace: #0
/usr/www/users/leuchtk/html/google-api/src/io/Google_REST.php(36):
Google_REST::decodeHttpResponse(Object(Google_HttpRequest))
#1 /usr/www/users/leuchtk/html/google-api/src/service/Google_ServiceResource.php(186):
Google_REST::execute(Object(Google_HttpRequest))
#2 /usr/www/users/leuchtk/html/google-api/src/contrib/Google_CalendarService.php(205):
Google_ServiceResource->__call('list', Array)
#3 /usr/www/users/leuchtk/html/i_termine_admin.php(55): Google_CalendarListServiceResource->listCalendarList()
#4 /usr/www/users/leuchtk/html/termine_admin.php(113): include('/usr/www/users/...')
#5 {main} thrown in /usr/www/users/leuchtk/html/google-api/src/io/Google_REST.php on line 66
So it looks like, the application is not logged in.
I am completely lost in this code for now.
Thank you for some little light, what is missing there...
Marco

Answer 1

You may want to refer to this question. Your issue could be just to add the
array('https://www.googleapis.com/auth/calendar', 'https://www.googleapis.com/auth/calendar.readonly'),
in where you call the
$client->setAssertionCredentials();
Google PHP Client API: Insufficient Permission
Hope this helps