fix: address trust proxy bypass and noisy 404s#507
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express-rate-limit v8.4+ rejects `trust proxy = true` because it allows anyone to spoof X-Forwarded-For and bypass rate limiting (ERR_ERL_PERMISSIVE_TRUST_PROXY). Setting it to 2 trusts exactly the two known proxy hops (Cloudflare → nginx → Express) while still resolving the correct client IP for logging and rate limiting.
sidvishnoi
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express-rate-limit v8.4+ rejects `trust proxy = true` because it allows anyone to spoof X-Forwarded-For and bypass rate limiting (ERR_ERL_PERMISSIVE_TRUST_PROXY). Setting it to 2 trusts exactly the two known proxy hops (Cloudflare → nginx → Express) while still resolving the correct client IP for logging and rate limiting.
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Summary
express-rate-limitv8.4+ throwsERR_ERL_PERMISSIVE_TRUST_PROXYbecauseapp.enable("trust proxy")sets it totrue, allowing anyone to spoofX-Forwarded-Forand bypass rate limiting. The production proxy chain is Client → Cloudflare → nginx → Express (PM2) (2 hops), so this changestrust proxyfromtrueto2.robots.txtandfavicon.icotostatic/. These two paths account for ~100 of the last 1000 error log entries from legitimate crawlers and browsers. The favicon is generated from the existingrespec-logo-square.pngat 32x32.Test plan
pnpm buildpassespnpm test— 40 specs, 0 failuresValidationErrorno longer appears in server logsreq.ip/:remote-addrstill logs real client IPs (not proxy IPs)/robots.txtand/favicon.icoreturn 200