@ima-worldhealth/sunfish/controllers/event-stream.js

A webapp for configuring DHIS2 email reports

const router = require('express').Router();
const dayjs = require('dayjs');
const executor = require('../lib/executor');

router.get('/schedule', (req, res) => {
  res.writeHead(200, {
    'Content-Type' : 'text/event-stream',
    'Cache-Control' : 'no-cache',
    Connection : 'keep-alive',
    'X-Accel-Buffering' : 'no',
  });

  res.write('\n');

  // listen for active events and fire them off
  executor.events.on('event', (message) => {
    const timestamp = dayjs().format('YYYY-MM-DD HH:mm:ss');

    const datapacket = {
      timestamp,
      message,
    };

    res.write(`id: ${Date.now()}\n`);
    res.write(`data: ${JSON.stringify(datapacket)}\n\n`);
    res.flushHeaders();
  });
});

module.exports = router;