calendar.gs

/**
 * Copyright Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
// [START apps_script_calendar_list_calendars]
/**
 * Lists the calendars shown in the user's calendar list.
 */
function listCalendars() {
  var calendars;
  var pageToken;
  do {
    calendars = Calendar.CalendarList.list({
      maxResults: 100,
      pageToken: pageToken
    });
    if (calendars.items && calendars.items.length > 0) {
      for (var i = 0; i < calendars.items.length; i++) {
        var calendar = calendars.items[i];
        Logger.log('%s (ID: %s)', calendar.summary, calendar.id);
      }
    } else {
      Logger.log('No calendars found.');
    }
    pageToken = calendars.nextPageToken;
  } while (pageToken);
}
// [END apps_script_calendar_list_calendars]

// [START apps_script_calendar_create_event]
/**
 * Creates an event in the user's default calendar.
 */
function createEvent() {
  var calendarId = 'primary';
  var start = getRelativeDate(1, 12);
  var end = getRelativeDate(1, 13);
  var event = {
    summary: 'Lunch Meeting',
    location: 'The Deli',
    description: 'To discuss our plans for the presentation next week.',
    start: {
      dateTime: start.toISOString()
    },
    end: {
      dateTime: end.toISOString()
    },
    attendees: [
      {email: 'alice@example.com'},
      {email: 'bob@example.com'}
    ],
    // Red background. Use Calendar.Colors.get() for the full list.
    colorId: 11
  };
  event = Calendar.Events.insert(event, calendarId);
  Logger.log('Event ID: ' + event.id);
}

/**
 * Helper function to get a new Date object relative to the current date.
 * @param {number} daysOffset The number of days in the future for the new date.
 * @param {number} hour The hour of the day for the new date, in the time zone
 *     of the script.
 * @return {Date} The new date.
 */
function getRelativeDate(daysOffset, hour) {
  var date = new Date();
  date.setDate(date.getDate() + daysOffset);
  date.setHours(hour);
  date.setMinutes(0);
  date.setSeconds(0);
  date.setMilliseconds(0);
  return date;
}
// [END apps_script_calendar_create_event]

// [START apps_script_calendar_list_events]
/**
 * Lists the next 10 upcoming events in the user's default calendar.
 */
function listNext10Events() {
  var calendarId = 'primary';
  var now = new Date();
  var events = Calendar.Events.list(calendarId, {
    timeMin: now.toISOString(),
    singleEvents: true,
    orderBy: 'startTime',
    maxResults: 10
  });
  if (events.items && events.items.length > 0) {
    for (var i = 0; i < events.items.length; i++) {
      var event = events.items[i];
      if (event.start.date) {
        // All-day event.
        var start = new Date(event.start.date);
        Logger.log('%s (%s)', event.summary, start.toLocaleDateString());
      } else {
        var start = new Date(event.start.dateTime);
        Logger.log('%s (%s)', event.summary, start.toLocaleString());
      }
    }
  } else {
    Logger.log('No events found.');
  }
}
// [END apps_script_calendar_list_events]

// [START apps_script_calendar_log_synced_events]
/**
 * Retrieve and log events from the given calendar that have been modified
 * since the last sync. If the sync token is missing or invalid, log all
 * events from up to a month ago (a full sync).
 *
 * @param {string} calendarId The ID of the calender to retrieve events from.
 * @param {boolean} fullSync If true, throw out any existing sync token and
 *        perform a full sync; if false, use the existing sync token if possible.
 */
function logSyncedEvents(calendarId, fullSync) {
  var properties = PropertiesService.getUserProperties();
  var options = {
    maxResults: 100
  };
  var syncToken = properties.getProperty('syncToken');
  if (syncToken && !fullSync) {
    options.syncToken = syncToken;
  } else {
    // Sync events up to thirty days in the past.
    options.timeMin = getRelativeDate(-30, 0).toISOString();
  }

  // Retrieve events one page at a time.
  var events;
  var pageToken;
  do {
    try {
      options.pageToken = pageToken;
      events = Calendar.Events.list(calendarId, options);
    } catch (e) {
      // Check to see if the sync token was invalidated by the server;
      // if so, perform a full sync instead.
      if (e.message === 'Sync token is no longer valid, a full sync is required.') {
        properties.deleteProperty('syncToken');
        logSyncedEvents(calendarId, true);
        return;
      } else {
        throw new Error(e.message);
      }
    }

    if (events.items && events.items.length > 0) {
      for (var i = 0; i < events.items.length; i++) {
         var event = events.items[i];
         if (event.status === 'cancelled') {
           console.log('Event id %s was cancelled.', event.id);
         } else if (event.start.date) {
           // All-day event.
           var start = new Date(event.start.date);
           console.log('%s (%s)', event.summary, start.toLocaleDateString());
         } else {
           // Events that don't last all day; they have defined start times.
           var start = new Date(event.start.dateTime);
           console.log('%s (%s)', event.summary, start.toLocaleString());
         }
      }
    } else {
      console.log('No events found.');
    }

    pageToken = events.nextPageToken;
  } while (pageToken);

  properties.setProperty('syncToken', events.nextSyncToken);
}
// [END apps_script_calendar_log_synced_events]

// [START apps_script_calendar_conditional_update]
/**
 * Creates an event in the user's default calendar, waits 30 seconds, then
 * attempts to update the event's location, on the condition that the event
 * has not been changed since it was created.  If the event is changed during
 * the 30-second wait, then the subsequent update will throw a 'Precondition
 * Failed' error.
 *
 * The conditional update is accomplished by setting the 'If-Match' header
 * to the etag of the new event when it was created.
 */
function conditionalUpdate() {
  var calendarId = 'primary';
  var start = getRelativeDate(1, 12);
  var end = getRelativeDate(1, 13);
  var event = {
    summary: 'Lunch Meeting',
    location: 'The Deli',
    description: 'To discuss our plans for the presentation next week.',
    start: {
      dateTime: start.toISOString()
    },
    end: {
      dateTime: end.toISOString()
    },
    attendees: [
      {email: 'alice@example.com'},
      {email: 'bob@example.com'}
    ],
    // Red background. Use Calendar.Colors.get() for the full list.
    colorId: 11
  };
  event = Calendar.Events.insert(event, calendarId);
  Logger.log('Event ID: ' + event.getId());
  // Wait 30 seconds to see if the event has been updated outside this script.
  Utilities.sleep(30 * 1000);
  // Try to update the event, on the condition that the event state has not
  // changed since the event was created.
  event.location = 'The Coffee Shop';
  try {
    event = Calendar.Events.update(
      event,
      calendarId,
      event.id,
      {},
      {'If-Match': event.etag}
    );
    Logger.log('Successfully updated event: ' + event.id);
  } catch (e) {
    Logger.log('Fetch threw an exception: ' + e);
  }
}
// [END apps_script_calendar_conditional_update]

// [START apps_script_calendar_conditional_fetch]
/**
 * Creates an event in the user's default calendar, then re-fetches the event
 * every second, on the condition that the event has changed since the last
 * fetch.
 *
 * The conditional fetch is accomplished by setting the 'If-None-Match' header
 * to the etag of the last known state of the event.
 */
function conditionalFetch() {
  var calendarId = 'primary';
  var start = getRelativeDate(1, 12);
  var end = getRelativeDate(1, 13);
  var event = {
    summary: 'Lunch Meeting',
    location: 'The Deli',
    description: 'To discuss our plans for the presentation next week.',
    start: {
      dateTime: start.toISOString()
    },
    end: {
      dateTime: end.toISOString()
    },
    attendees: [
      {email: 'alice@example.com'},
      {email: 'bob@example.com'}
    ],
    // Red background. Use Calendar.Colors.get() for the full list.
    colorId: 11
  };
  event = Calendar.Events.insert(event, calendarId);
  Logger.log('Event ID: ' + event.getId());
  // Re-fetch the event each second, but only get a result if it has changed.
  for (var i = 0; i < 30; i++) {
    Utilities.sleep(1000);
    try {
      event = Calendar.Events.get(calendarId, event.id, {}, {'If-None-Match': event.etag});
      Logger.log('New event description: ' + event.description);
    } catch (e) {
      Logger.log('Fetch threw an exception: ' + e);
    }
  }
}
// [END apps_script_calendar_conditional_fetch]