인증 없이 google-api-javascript-client(gapi) 사용[코드 예]

  // fill in your api key
  const apiKey = "******";
  // select a calendar by id
  const calendarId = "******";

  function start() {
    // Initializes the client with the API key and the Calendar API.
    gapi.client.init({
      'apiKey': apiKey,
      // load the correct library (calendar in this case)
      'discoveryDocs': ['https://www.googleapis.com/discovery/v1/apis/calendar/v3/rest'],
      'scopes': 'https://www.googleapis.com/auth/calendar.readonly'
    }).then(function() {
      return gapi.client.calendar.events.list({
        'calendarId': calendarId,
        'maxResults' : 5,
      });
    }).then(function(response) {
      console.log('response',response.result.items);
    }, function(reason) {
      console.log('Error: ', reason);
    });
  };
  // Loads the JavaScript client library and invokes `start` afterwards.
  gapi.load('client', start);