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

const base64 = require('base-64');

const utf8 = require('utf8');

​

async function gmailSendMessage() {

  try {

    const auth = await google.auth.getClient({

      scopes: ['https://www.googleapis.com/auth/gmail.send'],

    });

​

    const service = google.gmail({ version: 'v1', auth });

​

    const message = new Buffer.from('This is automated draft mail');

    const encodedMessage = base64.encode(utf8.encode(message.toString()));

​

    const emailMessage = [

      'To: gduser1@workspacesamples.dev',

      'From: gduser2@workspacesamples.dev',

      'Subject: Automated draft',

      '',

      encodedMessage,

    ].join('\r\n');

​

    const createMessage = {

      raw: base64.encode(utf8.encode(emailMessage)),

    };

​

    const sendMessage = await service.users.messages.send({

      userId: 'me',

      requestBody: createMessage,

    });

​

    console.log(`Message Id: ${sendMessage.data.id}`);

    return sendMessage.data;

  } catch (error) {

    console.error(`An error occurred: ${error.message}`);

    return null;

  }

}

​

if (require.main === module) {

  gmailSendMessage();

}