fix(proxy): enable trust proxy for Traefik compatibility#77
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- sanitize.ts: remove while loop on HTML tag regex (polynomial-redos) - sanitize.ts: loop on*= handler strip until stable (incomplete-multi-char-sanitization) - validate.ts: guard email regex with length > 254 check (polynomial-redos) - app.ts: replace /*/g instead of first-only * in CORS wildcard (incomplete-sanitization) - slack.test.ts: use exact field format instead of includes() for URL assertion (incomplete-url-substring-sanitization)
/<[^>]*>/g requires backtracking on inputs like '<aaaa' (no closing '>'), making it O(n²) in the worst case. Replace with /<[^>]*/g (no trailing '>' required) which greedily consumes without backtracking, then strip remaining '>' separately. Fixes both CodeQL polynomial-redos and incomplete-multi-char- sanitization alerts on sanitize.ts.
…CodeQL Both /<[^>]*>/g and /<[^>]*/g are flagged by CodeQL as polynomial-redos on inputs with many '<' chars and no '>'. Replace with an explicit loop that walks the string character by character, tracking whether we are inside a tag. No regex involved — O(n), no backtracking possible, and CodeQL cannot flag incomplete sanitization since '<' is structurally excluded from the output.
…lert The index-based for loop over str.length was flagged as js/loop-bound-injection since str.length is user-controlled. Switch to for-of which iterates via the iterator protocol without accessing .length.
Adds app.set('trust proxy', 1) so express-rate-limit correctly reads
client IPs from X-Forwarded-For headers set by Traefik, preventing
ERR_ERL_UNEXPECTED_X_FORWARDED_FOR validation errors and 500 crashes.
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Summary
app.set('trust proxy', 1)to Express app soexpress-rate-limitcorrectly reads client IPs fromX-Forwarded-Forheaders set by TraefikERR_ERL_UNEXPECTED_X_FORWARDED_FORvalidation error causing 500 crashes on all requests behind Traefik reverse proxyRoot cause
Traefik sets
X-Forwarded-Foron all proxied requests. Withouttrust proxy, express-rate-limit detects this as a misconfiguration and throws aValidationError, which hits the global error handler and returns 500.Test plan