Google Apps Script that copies Google calendar entries to a Google sheet

calendar-script.gs

/*
This Google script needs to be added to a Google spreadsheet.
It lists all calendar entries within one year (that time range is configurable)
and adds them to the first sheet in the spreadsheet. The script also adds
a button 'Update' in the spreadsheet's UI that executes the main update function.
*/

const spreadsheet = SpreadsheetApp.getActiveSpreadsheet();
const sheet = spreadsheet.getSheets()[0];

// one year in ms
const time_range = 365 * 24 * 60 * 60 * 1000;

// number of rows of table header, untouched by script
const offset = 1;

function update_events() {
  sheet.getRange(1 + offset,1,sheet.getLastRow(),sheet.getLastColumn()).clearContent();
  
  const now = new Date();
  const in_one_year = new Date(now.getTime() + time_range);
  const events = CalendarApp.getEvents(now,in_one_year);

  if (events.length === 0) return;
  
  const table_data = [];

  for (let i = 0; i < events.length; i++) {
    const event = events[i];
    const title = event.getTitle();
    const description = event.getDescription();
    const start_time = event.getStartTime().toLocaleString();
    const end_time = event.getEndTime().toLocaleString();
    const location = event.getLocation();
    const event_data = [title, description, start_time, end_time, location];
    table_data.push(event_data);
  }

  const range = sheet.getRange(1 + offset,1,events.length,table_data[0].length);
  range.setValues(table_data);
}

function onOpen() {
  SpreadsheetApp.getUi() 
        .createMenu("Actions")
        .addItem("Update", "update_events")
        .addToUi();
}

/*
appsscript.json
*/

/*
{
  "timeZone": "Europe/Berlin",
  "dependencies": {
  },
  "exceptionLogging": "STACKDRIVER",
  "runtimeVersion": "V8",
  "oauthScopes": [
    "https://www.googleapis.com/auth/spreadsheets",
    "https://www.googleapis.com/auth/calendar.readonly"
  ]
}
*/