start.ts

import { TOPIC } from '../consts'
import { kubo } from '../kubo'
import { createServer } from 'http'
import type { IncomingMessage, ServerResponse } from 'http'

const port = process.env.SUBMIT_GATEWAY_LISTEN_PORT || 3000
const host = '127.0.0.1'
const postgatewayUrl = `http://${host}:${port}`
const GATEWAY_LANDING_PAGE = `<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<meta name="viewport" content="width=device-width, initial-scale=1"/>
		<title>Datapod Gateway</title>
	</head>
	<body>
		<h1>Datapod Gateway</h1>
        <p>Use POST requests to submit data programatically. Alternatively, you can submit data manually in the form below for testing purpose.</p>
        <form method="post" action="${postgatewayUrl}" enctype='text/plain'>
            Blocks as base64 json list: 
            <input type="text" name="blocks" size=100 placeholder="['index request cid', 'index request as base64', 'data as base 64', 'optional aditionnal data as base64'...]"/>
            <input type="submit" value="Submit" />
        </form>
	</body>
</html>
`

// request handler
function handleRequest(request: IncomingMessage, response: ServerResponse<IncomingMessage>) {
  // use post requests to submit data
  if (request.method == 'POST') {
    let body = ''
    request.on('data', function (data) {
      body += data
    })
    request.on('end', function () {
      // hack to allow submitting data with form
      if (body.startsWith('blocks=')) {
        body = body.slice(7)
      }
      console.log('Body: ' + body)
      try {
        const blocks = JSON.parse(body)
        let first = true
        for (const b of blocks) {
          // first item is the index request CID
          if (first) {
            kubo.pubsub.publish(TOPIC, new TextEncoder().encode(b + '\n'))
            first = false
            continue
          }
          // other items are blocks
          const buffer = Buffer.from(b, 'base64')
          const bytes = new Uint8Array(buffer)
          kubo.block.put(bytes).then((cid) => {})
        }
        response.writeHead(200, { 'Content-Type': 'text/html' })
        response.end('data received and forwarded<br/>' + JSON.stringify(blocks, null, 4))
      } catch (e: any) {
        response.writeHead(400, { 'Content-Type': 'text/html' })
        response.end('invalid request\n' + e.toString())
      }
    })
  } else {
    var html = GATEWAY_LANDING_PAGE
    response.writeHead(200, { 'Content-Type': 'text/html' })
    response.end(html)
  }
}
const server = createServer(handleRequest)
server.listen(port)
console.log(`Listening on ${postgatewayUrl}`)