When a client connects over IPv6 loopback, net/http's RemoteAddr is
'[::1]:port'. The previous clientIP() returned '[::1]' (brackets and
all) which Postgres's INET type rejects:
'invalid input syntax for type inet: "[::1]" (SQLSTATE 22P02)'.
Live local-smoke caught this — every state-changing endpoint emitted
the audit event, the AppendAudit INSERT rolled back, and the warning
landed in the structured log. User-facing operation succeeded so the
caller never noticed; the audit_log table stayed empty.
Fix:
- Use net.SplitHostPort which returns IPv6 hosts without brackets.
- Add stripBrackets() as a belt-and-braces for X-Forwarded-For
headers that wrap the IP themselves (some proxies do).
Refs: M4.2
Full M4.2 deliverable: 16 endpoints (tenants CRUD + lifecycle, catalog, entitlements, API keys with argon2 hashing, audit append + filter), Store interface with pgx-backed Postgres + in-memory parallel implementations exercised by the same eachStore harness, openapi.yaml at 3.1 with kin-openapi contract test. M4.3 adds auth.
Refs: M4.2
sharang