gistfile1.txt

  // Create a new GoogleAuth instance with service-account credentials from a json file.
      // Note: credential file location must be set in GOOGLE_APPLICATION_CREDENTIALS env variable
      const auth = new google.auth.GoogleAuth({
        scopes: ['https://www.googleapis.com/auth/calendar'],
        clientOptions: {
          // Overwrite JWT subject to 'impersonate' calendar user
          subject: '[email protected]'
        }
      });

      this.calendar = google.calendar({
        version: 'v3',
        auth: await auth.getClient()
      });