# Node.js Integration — RenderPix
**API Endpoint:** `POST https://renderpix.dev/v1/render`
---
## Authentication
Pass your API key in the `X-API-Key` header on every request.
```js
const API_KEY = 'rpx_your_api_key';
const ENDPOINT = 'https://renderpix.dev/v1/render';
```
---
## Basic Example — HTML to PNG (fetch)
```js
const fs = require('fs');
async function renderHtml(html, outputFile = 'output.png') {
const res = await fetch('https://renderpix.dev/v1/render', {
method: 'POST',
headers: {
'X-API-Key': 'rpx_your_api_key',
'Content-Type': 'application/json',
},
body: JSON.stringify({
html,
width: 1200,
height: 630,
format: 'png',
}),
});
if (!res.ok) {
const err = await res.json().catch(() => ({}));
throw new Error(`RenderPix error ${res.status}: ${err.message || res.statusText}`);
}
const buffer = Buffer.from(await res.arrayBuffer());
fs.writeFileSync(outputFile, buffer);
console.log(`Saved to ${outputFile}`);
}
renderHtml('Hello, RenderPix!
');
```
---
## Basic Example — HTML to PNG (axios)
```js
const axios = require('axios');
const fs = require('fs');
async function renderHtml(html, outputFile = 'output.png') {
const response = await axios.post(
'https://renderpix.dev/v1/render',
{ html, width: 1200, height: 630, format: 'png' },
{
headers: {
'X-API-Key': 'rpx_your_api_key',
'Content-Type': 'application/json',
},
responseType: 'arraybuffer',
}
);
fs.writeFileSync(outputFile, response.data);
console.log(`Saved to ${outputFile}`);
}
renderHtml('Hello!
');
```
---
## Real-World Example — OG Image Generator
```js
const fs = require('fs');
async function generateOgImage({ title, description, domain, outputFile = 'og.png' }) {
const html = `
${domain}
${title}
${description}
`;
const res = await fetch('https://renderpix.dev/v1/render', {
method: 'POST',
headers: {
'X-API-Key': 'rpx_your_api_key',
'Content-Type': 'application/json',
},
body: JSON.stringify({ html, width: 1200, height: 630, format: 'png' }),
});
if (!res.ok) {
const err = await res.json().catch(() => ({}));
throw new Error(`Render failed (${res.status}): ${err.message || res.statusText}`);
}
const buffer = Buffer.from(await res.arrayBuffer());
fs.writeFileSync(outputFile, buffer);
return outputFile;
}
// Usage
generateOgImage({
title: 'Build Faster with RenderPix',
description: 'HTML to image in one API call. No puppeteer, no headless browser.',
domain: 'renderpix.dev',
outputFile: 'og-image.png',
}).then(file => console.log('OG image saved:', file));
```
---
## Response Handling
A successful render returns the image binary directly (`Content-Type: image/png` or `image/webp`).
```js
const res = await fetch('https://renderpix.dev/v1/render', { /* ... */ });
// Check status first
if (res.status === 200) {
const contentType = res.headers.get('content-type'); // 'image/png'
const buffer = Buffer.from(await res.arrayBuffer());
// buffer contains the raw image bytes
}
```
---
## Error Handling
```js
async function renderSafe(html) {
let res;
try {
res = await fetch('https://renderpix.dev/v1/render', {
method: 'POST',
headers: {
'X-API-Key': 'rpx_your_api_key',
'Content-Type': 'application/json',
},
body: JSON.stringify({ html, width: 1200, height: 630 }),
});
} catch (networkErr) {
console.error('Network error:', networkErr.message);
return null;
}
if (!res.ok) {
const body = await res.json().catch(() => ({}));
switch (res.status) {
case 401: throw new Error('Invalid API key — check X-API-Key header');
case 429: throw new Error('Rate limit exceeded — slow down or upgrade plan');
case 422: throw new Error(`Invalid request: ${body.message}`);
default: throw new Error(`Render failed (${res.status}): ${body.message || 'unknown error'}`);
}
}
return Buffer.from(await res.arrayBuffer());
}
```
---
## Next.js / Edge Runtime Example
```js
// app/api/og/route.js
export async function GET(request) {
const { searchParams } = new URL(request.url);
const title = searchParams.get('title') || 'Untitled';
const html = `${title}
`;
const res = await fetch('https://renderpix.dev/v1/render', {
method: 'POST',
headers: {
'X-API-Key': process.env.RENDERPIX_API_KEY,
'Content-Type': 'application/json',
},
body: JSON.stringify({ html, width: 1200, height: 630, format: 'png' }),
});
if (!res.ok) return new Response('Render failed', { status: 500 });
const image = await res.arrayBuffer();
return new Response(image, {
headers: { 'Content-Type': 'image/png', 'Cache-Control': 'public, max-age=86400' },
});
}
```