Adding events in bulk to Google Calendar API with PHP -

what best way add possibly 10,000 20,000 events @ once google calendar php?

if try adding them separately "limit exceeded" error far before daily max.

i've been looking @ importing ical/ics files can't seem find function besides calendar subscriptions. calendar subscriptions great need have "real-time" updates in calendars when event gets changed , it's unclear when calendar subscriptions updated take as day initial change in ics file.

need use batch requests. batch request consists of multiple api calls combined 1 http request. batch processing known feature request , actively worked on. read following article it: https://developers.google.com/google-apps/calendar/batch

see multipleinsert function example:

class my_google_calendar {   ...    /** add single event student */   function addevent($lesson, $instructor, $return_request = false, $enable_attendees = false)   {     $calendar = $this->getgooglecalendar(); // calendar service variable      $lesson_from = date(date_rfc3339, $lesson->from);     $lesson_to = date(date_rfc3339, $lesson->from + $lesson->duration);       $event = new google_service_calendar_event();     $event->setsummary('lesson student: '$lesson->student_full_name);      $start = new google_service_calendar_eventdatetime();     $start->setdatetime($lesson_from);      $start->settimezone($this->getgooglecalendartimezone());     $event->setstart($start);      $end = new google_service_calendar_eventdatetime();     $end->setdatetime($lesson_to);     $end->settimezone($this->getgooglecalendartimezone());     $event->setend($end);     $event->setcolorid(4);      $description = "...";     $event->setdescription($description);      if (isset($student->email) && $enable_attendees) {       $attendee1 = new google_service_calendar_eventattendee();       $attendee1->setresponsestatus('needsaction');       $attendee1->setemail($student->email);       $attendees = array($attendee1);       $event->setattendees($attendees);     }      $createdevent = $this->calendar->events->insert($this->calendar_id, $event, array('fields' => 'id'));     return $return_request ? $createdevent : $createdevent->getid();   }    /** push group of events calendar */   function multipleinsert ($lessons, $instructor)   {     $this->use_batch = true;     $this->client->setusebatch($this->use_batch);     $batch = new google_http_batch($this->client);      foreach($lessons $time => $lesson) {               $lesson = array_shift($group['lessons']);         $req = $this->addevent($lesson, $instructor, true);         $batch->add($req, $time);       }     }     $results = $batch->execute();      return $results;   }  }