HTML to Image
in Node.js — no Puppeteer

// render.js — works anywhere Node 18+ fetch is available
export async function htmlToImage(html, { width = 1200, height = 630 } = {}) {
  const res = await fetch('https://api.renderpix.dev/v1/render', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'Authorization': `Bearer ${process.env.RENDERPIX_API_KEY}`,
    },
    body: JSON.stringify({ html, width, height, format: 'png' }),
  })

  if (!res.ok) throw new Error(`RenderPix error: ${res.status}`)

  const { url } = await res.json()
  const img = await fetch(url)
  return Buffer.from(await img.arrayBuffer())
}

// routes/og.js — Express endpoint that streams PNG
import express from 'express'
import { htmlToImage } from './render.js'

const router = express.Router()

router.get('/og', async (req, res) => {
  const { title = 'Untitled', author = '' } = req.query

  const html = `
    <div style="width:1200px;height:630px;background:#0f172a;
      display:flex;flex-direction:column;justify-content:flex-end;
      padding:72px;font-family:sans-serif">
      <h1 style="color:#f8fafc;font-size:52px;font-weight:700;
        line-height:1.2;max-width:900px">${title}</h1>
      <p style="color:#94a3b8;font-size:20px;margin-top:24px">${author}</p>
    </div>`

  const png = await htmlToImage(html)

  res
    .set('Content-Type', 'image/png')
    .set('Cache-Control', 'public, max-age=86400')
    .send(png)
})

export default router

// handler.mjs — AWS Lambda (Node 20 runtime)
export const handler = async (event) => {
  const title = event.queryStringParameters?.title ?? 'Hello'

  const html = `<div style="width:1200px;height:630px;
    background:linear-gradient(135deg,#1e1b4b,#0f172a);
    display:flex;align-items:center;justify-content:center">
    <h1 style="color:white;font-size:60px;font-family:sans-serif">
      ${title}
    </h1></div>`

  const res = await fetch('https://api.renderpix.dev/v1/render', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${process.env.RENDERPIX_API_KEY}`,
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({ html, width: 1200, height: 630 }),
  })
  const { url } = await res.json()
  const img = await fetch(url)
  const buf = Buffer.from(await img.arrayBuffer())

  return {
    statusCode: 200,
    headers: { 'Content-Type': 'image/png',
               'Cache-Control': 'public,max-age=86400' },
    body: buf.toString('base64'),
    isBase64Encoded: true,
  }
}