fix(alerting): hard timeout on ANS raise — admin test alert fails fast instead of 502 - #1505
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…t 502 The ANS sink (@sap-tutorials/cds-alert-notification) delivers via a raw fetch with no client-side timeout. A hung ANS connection (e.g. blocked CF egress) makes svc.raise() block forever — neither resolving nor throwing — so the existing fail-open try/catch is powerless. In PROD this held the srv worker ~86s until CF dropped the socket, surfacing as a 502 Gateway Timeout on the admin 'Send test alert'. raiseWithTimeout() races every raise against a 5s deadline. A stuck delivery now fails fast: raise() swallows it (unchanged fail-open contract), and raiseTest() returns outcome:'timeout' with a clear reason so the admin sees what happened. Belt-and-braces with the AbortController timeout added plugin-side (v1.0.2).
This was referenced Aug 6, 2026
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Problem
After the kinds fix (#1503) made
cds.connect.to('alerts')succeed, the admin Send test alert started failing with Gateway Timeout. PROD srv log:POST /admin/ChatSettings/AdminService.sendTestAlert → 502 endpoint_failure (EOF) response_time:86.3s.Root cause
The ANS sink in
@sap-tutorials/cds-alert-notification(lib/sinks/ans-client.js) delivers via a rawglobalThis.fetchwith no AbortController/timeout. A hung ANS connection (blocked CF egress is the prime suspect — both ANS endpoints answer <1s from a workstation butcf sshis disabled on PROD so container egress couldn't be probed directly) makessvc.raise()block forever: it neither resolves nor throws. The existing fail-opentry/catchinalerting.jsis powerless against an unresolved promise, so the srv worker held the socket ~86s until CF dropped it → 502.Fix (consumer stopgap)
raiseWithTimeout()races every raise against a 5s deadline:raise()(production hooks) — swallows the timeout, unchanged fail-open contract.raiseTest()(admin action) — returnsoutcome: 'timeout'with a clear reason, so the admin UI shows what happened instead of a 502.outcome: Stringin the CDS return type is free-form, so'timeout'flows through the existing handler untouched.Tests
2 new unit tests (fake timers): a never-resolving
raiseyieldsoutcome:'timeout'inraiseTest, andraise()returns cleanly without hanging. Full alerting suite 13/13, admin-send-test-alert 5/5.Follow-up
Companion plugin fix adds an AbortController timeout inside
ans-client.js(v1.0.2, separate PR) as belt-and-braces. Note: even with both timeouts, if CF→ANS egress is genuinely blocked, alerts fail fast and clean rather than delivering — that's a separate BTP networking question this fix stops masking.