API Reference

SDK

Official client libraries available on GitHub.

PHP

$pdf = new Funbrew\Pdf\FunbrewPdf('sk-your-api-key');
$result = $pdf->fromHtml('<h1>Hello</h1>');
echo $result['data']['download_url'];

Node.js

const { FunbrewPdf } = require('@funbrew/pdf');
const pdf = new FunbrewPdf('sk-your-api-key');
const result = await pdf.fromHtml('<h1>Hello</h1>');
console.log(result.data.download_url);

Python

from funbrew_pdf import FunbrewPdf
pdf = FunbrewPdf("sk-your-api-key")
result = pdf.from_html("<h1>Hello</h1>")
print(result["data"]["download_url"])

Authentication

All API requests require an API key. Include it as a Bearer Token in the request header.

Authorization: Bearer sk-your-api-key

X-API-Key You can also authenticate via the X-API-Key header or the ?api_key=... query parameter.

API keys can be issued from the dashboard. The key is shown only once at creation — store it securely.

PDF Engine Selection

FUNBREW PDF offers two rendering engines. The default is the Chromium-based high-quality engine.

// Generate with Chromium engine (default)
{
  "html": "<div style='display:flex'>...</div>",
  "options": { "engine": "quality" }
}

When engine is not specified, quality (Chromium) is used. Use engine=fast for high-throughput batch generation.

Rate Limiting

API requests are subject to per-minute rate limits based on your plan.

Response Headers

All API responses include the following headers.

When Exceeded

When the limit is exceeded, a 429 Too Many Requests response is returned. Wait for the number of seconds in the Retry-After header before retrying.

{
  "success": false,
  "message": "Rate limit exceeded. Please retry later.",
  "retry_after": 42
}

HTML → PDF

Generate a PDF from HTML content.

Parameters

Request Example

curl -X POST https://your-domain/api/pdf/generate-from-html \
  -H "Authorization: Bearer sk-your-api-key" \
  -H "Content-Type: application/json" \
  -d '{"html": "<h1>Hello</h1>", "options": {"page-size": "A4"}}'

Response

{
  "success": true,
  "data": {
    "filename": "uuid.pdf",
    "original_name": "請求書_2026年3月.pdf",
    "download_url": "https://.../api/pdf/download/uuid.pdf",
    "file_size": 45321,
    "expires_at": "2026-03-21T12:00:00.000000Z",
    "max_downloads": 10,
    "remaining_downloads": 10
  }
}

URL → PDF

Convert a web page specified by URL to PDF.

Template → PDF

Generate a PDF by injecting variables into a pre-registered template.

Batch Generation

Generate multiple PDFs asynchronously in batch.

Check batch progress status.

PDF Merge

Merge multiple existing PDFs into one.

Download

Download a generated PDF. Increments the download count.

File Info

Get PDF file metadata (size, remaining downloads, expiry, etc.).

File Delete

Delete a PDF file.

Template CRUD

List all templates.

Create a template. Use variable placeholders in html_content.

Email Delivery

Send generated PDFs as email attachments. Two methods are available.

A) Specify in API request

Add the email parameter to your generation request to send the PDF as an attachment after generation.

curl -X POST https://your-domain/api/pdf/generate-from-html \
  -H "Authorization: Bearer sk-your-api-key" \
  -H "Content-Type: application/json" \
  -d '{
    "html": "<h1>請求書</h1>",
    "email": {
      "to": "customer@example.com",
      "subject": "請求書をお送りします",
      "body": "添付の請求書をご確認ください。"
    }
  }'

B) Pre-configure in dashboard

Set up recipient, subject, and body templates in Email Notification Settings. Emails are sent automatically on every PDF generation.

The following placeholders can be used in subject and body:

Webhook / Slack Notifications

Register a webhook URL. Events are sent via POST.

Supported Events

Slack Integration

When you specify a Slack Incoming Webhook URL, notifications are automatically formatted as Slack Block Kit messages with download buttons.

Webhook and Slack notifications can also be configured from the dashboard.

Signature Verification

Standard webhooks include a X-Webhook-Signature: sha256=HMAC(payload, secret) header.

Usage

Returns current month's usage count, remaining quota, plan info, and enabled features.

S3 Storage Integration

Auto-upload generated PDFs to AWS S3 or S3-compatible services. When configured, PDFs are saved to both local and S3 storage, and the response includes an s3_url.

Configure from the dashboard. Also available via API:

Credentials are encrypted at rest on the server.

Error Codes

All error responses follow this format:

{ "success": false, "message": "Error description" }