manifold/og-image/api/index.ts

import { IncomingMessage, ServerResponse } from 'http'
import { parseRequest } from './_lib/parser'
import { getScreenshot } from './_lib/chromium'
import { getHtml } from './_lib/template'
import { getChallengeHtml } from './_lib/challenge-template'

const isDev = !process.env.AWS_REGION
const isHtmlDebug = process.env.OG_HTML_DEBUG === '1'

export default async function handler(
  req: IncomingMessage,
  res: ServerResponse
) {
  try {
    const parsedReq = parseRequest(req)
    let html = getHtml(parsedReq)
    if (parsedReq.challengerOutcome) html = getChallengeHtml(parsedReq)
    if (isHtmlDebug) {
      res.setHeader('Content-Type', 'text/html')
      res.end(html)
      return
    }
    const { fileType } = parsedReq
    const file = await getScreenshot(html, fileType, isDev)
    res.statusCode = 200
    res.setHeader('Content-Type', `image/${fileType}`)
    res.setHeader(
      'Cache-Control',
      `public, immutable, no-transform, s-maxage=31536000, max-age=31536000`
    )
    res.end(file)
  } catch (e) {
    res.statusCode = 500
    res.setHeader('Content-Type', 'text/html')
    res.end('<h1>Internal Error</h1><p>Sorry, there was a problem</p>')
    console.error(e)
  }
}