calendar.js

const fs = require('fs');
const readline = require('readline');
const { google } = require('googleapis');

// If modifying these scopes, delete token.json.
const SCOPES = ['https://www.googleapis.com/auth/calendar'];
// The file token.json stores the user's access and refresh tokens, and is
// created automatically when the authorization flow completes for the first
// time.
const TOKEN_PATH = `token.json`;

// Load client secrets from a local file.
const GoogleCalendar = (userEmail, appointmentDate, device) => {
  console.log(userEmail, appointmentDate, device);
  fs.readFile(`GC.json`, (err, content) => {
    if (err) return console.log('Error loading client secret file:', err);
    // Authorize a client with credentials, then call the Google Calendar API.
    authorize(JSON.parse(content), createEvent);
  });
  function authorize(credentials, callback) {
    const { client_secret, client_id, redirect_uris } = credentials.installed;
    const oAuth2Client = new google.auth.OAuth2(
      client_id,
      client_secret,
      redirect_uris[0]
    );

    // Check if we have previously stored a token.
    fs.readFile(TOKEN_PATH, (err, token) => {
      if (err) return getAccessToken(oAuth2Client, callback);
      oAuth2Client.setCredentials(JSON.parse(token));
      callback(oAuth2Client);
    });
  }

  function getAccessToken(oAuth2Client, callback) {
    const authUrl = oAuth2Client.generateAuthUrl({
      access_type: 'offline',
      scope: SCOPES
    });
    console.log('Authorize this app by visiting this url:', authUrl);
    const rl = readline.createInterface({
      input: process.stdin,
      output: process.stdout
    });
    rl.question('Enter the code from that page here: ', code => {
      rl.close();
      oAuth2Client.getToken(code, (err, token) => {
        if (err) return console.error('Error retrieving access token', err);
        oAuth2Client.setCredentials(token);
        // Store the token to disk for later program executions
        fs.writeFile(TOKEN_PATH, JSON.stringify(token), err => {
          if (err) return console.error(err);
          console.log('Token stored to', TOKEN_PATH);
        });
        callback(oAuth2Client);
      });
    });
  }

  function createEvent(auth) {
    const calendar = google.calendar({ version: 'v3', auth });
    let event = {
      summary: 'Appointment',
      location: '92 El Tahrir, Ad Doqi, Dokki, Giza Governorate',
      description: device,
      start: {
        dateTime: appointmentDate,
        timeZone: 'Africa/Cairo'
      },
      end: {
        dateTime: appointmentDate,
        timeZone: 'Africa/Cairo'
      },
      reminders: {
        useDefault: false,
        overrides: [
          { method: 'email', minutes: 24 * 60 },
          { method: 'popup', minutes: 10 }
        ]
      }
    };

    calendar.events.insert(
      {
        auth: auth,
        calendarId: 'primary',
        resource: event
      },
      function(err, event) {
        if (err) {
          console.log(
            'There was an error contacting the Calendar service: ' + err
          );
          return;
        }
        //console.log('Event created: %s', event);
      }
    );
  }
};

module.exports = GoogleCalendar;