Phase 9 first commit. Three middleware additions that the token
handler + service will consume.
- realip.go: RealIP(r) + OptionalHeader(v) + lastNonEmptyXFF —
promotion of the helpers currently duplicated across webbug/
slowredirect/docx/pdf/kubeconfig/envfile/mysql generators. The
bodies are byte-identical to those copies. Phase 9 task 9.8
refactors webbug to use this shared helper next; the other
generators' duplication remains until Phase 10's Trigger plumbing
refactor (Phase 9 keeps the scope to webbug per the plan)
- fingerprint.go: ExtractFingerprint(r) = hex(sha256(realIP|UA))[:16]
+ KeyByFingerprint(r) = "ratelimit:fp:" + fp, per spec §11.2
lines 1568-1591. The 16-char prefix is a deliberate space/
collision trade-off documented in the spec — full sha256 is 64
chars, 16 chars = 64 bits ≈ 1e19 keyspace, fine for fingerprint
rate-limiting where collisions are caught by the rate limit
granularity anyway
- recovery.go: Recovery(logger) middleware — defer recover(),
logs panic + request_id + path + stack, writes a 500 with the
project's standard {success:false, error:{code,message}}
envelope. Per spec §11.1 line 1543
Tests (~16 cases): 11 source-IP precedence cases matching the
generator suites + OptionalHeader empty/whitespace/value + fingerprint
determinism/length/hex-format/different-IPs-distinct + KeyByFingerprint
prefix + recovery panic-returns-500 + recovery passes-through-non-panic
+ recovery logs request ID through the RequestID middleware chain.
Phase 9 task 9.1 + 9.4 discharged.
c988e4b902