fix: ignore font and modern static-asset extensions#71
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Add .ttf, .otf, .woff, .woff2, .eot, .svg, .webp, .avif and .webmanifest to @extensions_to_ignore and remove the duplicated .doc entry. The list previously ended at .torrent, so no font, SVG or modern image format was filtered at all: every bot request for such an asset was forwarded to the Prerender service, which rejects static assets with 504. Verified live that Googlebot requesting prerender.io's own inter-*.woff2 receives a 504 (a normal UA gets 200), so these forwarded requests surface as crawler-visible 5xx. Aligns with the canonical static-asset ignore list in prerender/integration-contract#1. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
OpsBeaconCharles
approved these changes
Jun 12, 2026
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Bug
@extensions_to_ignoreends at.torrent— there is no font, SVG, or modern image filtering at all. Every bot request for a.woff2/.ttf/.svg/.webp/etc. asset is forwarded to the Prerender service, which rejects static-asset URLs with 504. The result is a crawler-visible 5xx for every font/image a bot fetches through the middleware.Live evidence
Verified against prerender.io's own assets: requesting
inter-*.woff2with a Googlebot user agent returns 504, while a normal browser UA returns 200.Canonical contract
This aligns the middleware with the canonical static-asset ignore list, which now includes
.woff2 .otf .eot .webp .avif .webmanifest: prerender/integration-contract#1Changes
lib/prerender_rails.rb: add.ttf .otf .woff .woff2 .eot .svg .webp .avif .webmanifestto@extensions_to_ignore; remove the duplicated.docentry.test/lib/prerender_rails.rb: add a test mirroring the existing resource-file test for a font request (/fonts/inter.woff2) asserting the request continues to the app instead of being proxied.Matching semantics are deliberately left as-is: the check is
request.fullpath.include?(extension)— a case-sensitive substring match over path and query string. Side note: this already over-matches today (e.g..aimatches any URL containing.ai, such asexample.aidomains in query params, and/blog/what-is-a-pdfis unaffected but?file=x.pdfis filtered); tightening that to a real extension check is out of scope for this PR.Tests
bundle install && ruby -Ilib test/lib/prerender_rails.rb(Ruby 2.6.10, Bundler 2.1.4;RUBYOPT=-rloggerto work around the unrelated concurrent-ruby 1.3.5 / ActiveSupport 6.1Loggerautoload issue): 28 runs, 36 assertions, 0 failures, 0 errors, including the new font test.🤖 Generated with Claude Code