A dockerized web service for creating PDFs from HTML using WeasyPrint

WeasyPrint is a visual rendering engine for HTML and CSS that can export to PDF. It aims to support web standards for printing.

This web service exposes an endpoint for uploading a html file, an optional css file and optional attachments. It responds with the generated PDF.

The web service is written in Python using the aiohttp web server.

To start the webservice just run

docker compose up

The html file and and any additional files must be uploaded as multipart/form-data with a part named html containing the main HTML content. Assets (e.g. images) that are referenced in HTML must be prefixed with asset.. Files that should be attached to the generated pdf must be prefixed with attachment.

Example:

curl -F "html=@tests/index.html" -F "asset.universe.jpg=@tests/universe.jpg" http:https://localhost:3000 -o test.pdf

It's possible to overwrite some weasyprint.DEFAULT_OPTIONS by including a part named options in JSON format.

Example:

curl -F "html=@tests/index.html" -F "asset.universe.jpg=@tests/universe.jpg" -F options='{"pdf_variant": "pdf/a-3b"};type=application/json' http:https://localhost:3000 -o test.pdf

By default fetching external resource is prohibited for security reasons. To allow fetching resources from external urls, set the environment variable WEASYPRINT_ALLOWED_URLS_PATTERN to a regex pattern that matches your desired urls.

Example:

WEASYPRINT_ALLOWED_URLS_PATTERN="^https://fonts\.example\.com.*|^https://logos\.example\.com.*"