JavaScript / TypeScript SDK

The official JS/TS SDK is published as docjet on npm. Zero runtime dependencies; requires Node.js 18+ (native fetch).

Install

npm install docjet

Render a PDF

import { DocJetClient } from 'docjet';

const client = new DocJetClient({ apiKey: process.env.DOCJET_API_KEY! });

// Returns a signed download URL
const { url } = await client.render({
  template_id: 'invoice-ro',
  data: {
    client: 'Acme SRL',
    total: 1500,
    currency: 'RON',
  },
});

console.log('PDF ready:', url);

Raw HTML instead of a template

const { url } = await client.render({
  html: '<h1>Hello World</h1><p>Generated by DocJet.</p>',
  data: { name: 'World' },
});

PNG images, templates, usage

// PNG (e.g. OG/social card) — dimensions come from the template
const image = await client.renderImage({
  template_id: 'og-blog',
  data: { title: 'My Article', author: 'Me' },
});

// Public template catalog
const templates = await client.listTemplates();

// Current-period usage
const usage = await client.usage();

Verify webhook signatures

Every async DocJet callback is signed with an X-DocJet-Signature header. Verify it before trusting the payload — one call, timing-safe, with a 5-minute replay window:

import { verifyWebhookSignature } from 'docjet';

app.post('/webhooks/docjet', (req, res) => {
  const rawBody = req.body; // raw string BEFORE JSON.parse — critical!
  const signature = req.headers['x-docjet-signature'] as string;
  const secret = process.env.DOCJET_WEBHOOK_SECRET!;

  if (!verifyWebhookSignature(rawBody, signature, secret)) {
    return res.status(401).json({ error: 'Invalid signature' });
  }

  const event = JSON.parse(rawBody); // now safe to trust
  res.json({ received: true });
});

Get your signing secret with GET /v1/keys/webhook-secret. Full scheme details: Webhooks & signatures.

Error handling

Non-2xx responses throw DocJetError with the API error code and HTTP status:

import { DocJetClient, DocJetError } from 'docjet';

try {
  const { url } = await client.render({ template_id: 'invoice-ro', data: {} });
} catch (err) {
  if (err instanceof DocJetError) {
    console.error(`[${err.code}] HTTP ${err.statusCode}: ${err.message}`);
    // err.code: 'AUTH_INVALID' | 'QUOTA_EXCEEDED' | 'RATE_LIMITED' | ...
  } else {
    throw err;
  }
}

See the full taxonomy in Errors & limits.

Configuration

const client = new DocJetClient({
  apiKey: 'binfra_...',              // required
  baseUrl: 'https://api.docjet.dev', // optional, default shown
});