ok, i figured this out. i was confused as the documentation on this is quite confusing at least to me.
$events is indeed the correct list, but the reason it doesn't contain all the properties mentioned in the docs is that some properties have to be retrieved via method invocation. so what we'll need to do is:
// start of first event
$startDate = $events[0]->getStart();
this is what my entire script looks like now. excuse my php, never used it before
<?php
header('Content-type: application/json');
include_once __DIR__ . '/vendor/autoload.php';
$client = new Google_Client();
$client->setAuthConfig('your service account json secret');
$client->setApplicationName('your application name');
$client->setScopes(['https://www.googleapis.com/auth/calendar.readonly']);
$service = new Google_Service_Calendar($client);
// make actual request
$calendarId = 'your calendar id';
$optParams = array(
'timeMin' => date('c'),
'maxResults' => 100,
'singleEvents' => TRUE,
'orderBy' => 'startTime',
);
// of type Events.php
$events = $service->events;
// list of items of type Event.php
$eventItems = $events->listEvents($calendarId, $optParams)->getItems();
// compose an result object, we're only interested in summary, location and dateTime atm
// don't know if this is considered proper php code, works though
$result = array();
for ($i = 0; $i < count($eventItems); $i++)
{
$result[$i]->{summary} = $eventItems[$i]->getSummary();
$result[$i]->{location} = $eventItems[$i]->getLocation();
$result[$i]->{startDate} = $eventItems[$i]->getStart()->getDateTime();
}
echo json_encode($result);
?>