NFR Design for U3 and U4. Two decisions the earlier stages had deliberately
left open, plus four risks the functional design did not name.
OPEN-01 closed: the correlation ID is the W3C trace ID from the ambient
Activity, with TraceIdentifier as the fallback. It propagates across the
master/slave boundary via traceparent, which TraceIdentifier cannot do at
all, and it is the same value ProblemDetails already returns to the client.
REF-U3-01 raised: BR-U3-22's Umami-origin startup warning cannot work. The
backend never sees VITE_UMAMI_WEBSITE_ID, so the check would either always
warn or never warn. Withdrawn from U3 and replaced by a blocking U5 CI gate
that compares the frontend build variable against that environment's CSP
origins, where both values are visible.
Four additions beyond the functional design:
- Set-Cookie added to the scrub list; the login response issues the
refreshToken there, so scrubbing only the request cookie protects nothing
- SetBeforeSendTransaction alongside SetBeforeSend; transactions carry
request data too
- OnRejected on the rate limiter; today a 429 leaves no trace anywhere
- FlushAsync before the migration-failure rethrow, or the one Critical
event in the system dies with the process
Two traps recorded with tests attached: Sentry groups log events by message
template, so interpolated messages make FR-19's rate-based alert rules
unimplementable while appearing to work; and DefaultHttpContext.Response
.OnStarting is a no-op, so the obvious middleware test asserts nothing.
Three values chosen rather than escalated, each one line to change and all
three listed for review at the end of U4's pattern document: JSON console
outside Development, TracesSampleRate 0.1, tunnel cap 200 KB.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HHoJpxYXzHACSQguHrC5fw