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"Fix: PDF rendering timeout on page.goto with networkidle" #800

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"Fix: PDF rendering timeout on page.goto with networkidle" #800

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10 changes: 7 additions & 3 deletions apps/backend/app/pdf.py
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Original file line number Diff line number Diff line change
Expand Up @@ -133,9 +133,13 @@ async def _render_page_to_pdf(
pdf_format: str,
pdf_margins: dict,
) -> bytes:
await page.goto(url, wait_until="networkidle")
await page.wait_for_selector(selector)
await page.evaluate("document.fonts.ready")
await page.goto(url, wait_until="domcontentloaded", timeout=15000)

@Frankli9986 Frankli9986 May 21, 2026

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Great fix! The domcontentloaded strategy is the right approach for static PDF rendering.

One suggestion: the bare except Exception: pass on document.fonts.ready silently swallows font loading failures, which makes production debugging difficult. Consider adding a logger.warning(...) so operators can see when fonts fail to load without blocking PDF generation.

Example:

try:
    await page.evaluate("document.fonts.ready", timeout=10000)
except Exception as e:
    logger.warning(f"Font loading failed for PDF generation (non-critical): {e}")

This is a small addition but significantly improves observability in production environments.

@vinsmokejazz vinsmokejazz May 25, 2026

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Thanks for the review and the suggestion!

You're absolutely right, silently swallowing the exception reduces visibility into font-loading issues in production. Adding a non-blocking warning log is a good balance between reliability and observability

await page.wait_for_selector(selector, timeout=10000)
try:
await page.evaluate("document.fonts.ready", timeout=10000)
except Exception:
# Font loading is not critical for PDF rendering
pass
return await page.pdf(
format=pdf_format,
print_background=True,
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