FastAPI and Playwright Generate PDF and PNG Documents in Under 4 Seconds

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Mohamed Amine Ben Mallessa, Lead Developer at Sollea AI, published a tutorial detailing a server-side document generation pipeline using Playwright with a headless Chromium browser and FastAPI. The system converts an HTML template into a vector PDF (A4) and a high-resolution PNG (300 dpi, 2480×3508px) in approximately 3.5 seconds per document. Data is injected into a self-contained HTML file via JavaScript's postMessage API, eliminating the need for external SaaS tools like Canva or Adobe. The same template serves both live browser previews and final server-side rendering, avoiding any divergence between preview and production output. The approach was chosen over alternatives like wkhtmltopdf and Puppeteer for its reliability, native font handling, and clean integration with FastAPI.

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