2 Commits

Author SHA1 Message Date
Joseph Doherty 081fa693af fix(s7): access-denied is an answer; review round-1 minors (R07:H4 follow-through)
I-1: a PUT/GET-disabled CPU (every read denied) stayed Faulted with
LastSuccessfulRead frozen, so the comms-loss watchdog reconnected and
re-subscribed it every 90 s forever. Both access-denied arms now also record
an answer: Faulted is kept (worst state wins), the stamp advances, and the
sticky write fault still clears only on a real success. Pinned end to end in
Runtime.Tests: the real S7Driver under the real DriverInstanceActor watchdog
is not reconnected across 2x the threshold; the control (every read timing
out) is.

Minors:
- m-1: injectable pass clock (UtcNow); "LastSuccessfulRead advanced" is now
  asserted strictly, including the write-refusal case.
- m-2: the editor uses S7TagShapeRules.IsByteAnchored instead of its own list.
- m-3: a release that races an init publish also cancels the probe loop the
  publish started after the release took its snapshot.
- m-4: a retained poll failing during a lifecycle operation writes no health.
- m-5: a multi-var chunk that fell back memoises its members refused alone.
- m-7: access-denied needs S7.Net's exact wording and no transport fault in
  the chain.
- m-8: sync teardown clears the write-side Degraded owner; a sync Dispose
  racing a running shutdown is tested.

Refs #742
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
2026-10-22 15:57:53 -04:00
Joseph Doherty a1f20e78f9 fix(s7): a CPU refusal is per-tag Bad and counts as answered (R07:H4)
A deterministic PLC refusal (object does not exist, address out of range,
type inconsistent...) degraded driver health, and an all-refused driver (a
wrong DB number) sat Degraded with LastSuccessfulRead frozen, so the 90 s
comms-loss watchdog reconnected it forever against a reachable PLC.

- IsRefusal / IsAccessDenied classify over the whole exception chain. Live
  probe on the snap7 fixture: S7.Net's READ paths raise the item error as a
  BARE Exception ("Received error from PLC: ..."), its write paths as
  PlcException(WriteData). The old PlcException-only match missed the read
  shape entirely, so a real read access-denied was BadCommunicationError +
  Degraded instead of the Faulted PUT/GET alert; the Test Connect probe had
  the same blind spot.
- A refusal (read or write) is BadDeviceFailure with a once-per-tag Warning,
  no health write and no reopen; it counts as answered, so it advances
  LastSuccessfulRead and restores Healthy after a comms fault. An undecodable
  buffer (S7ValueRangeException) also counts as answered.
- A write batch the CPU answered without a failure advances
  LastSuccessfulRead and retires a Degraded the write side itself published.
- Tests that used ReadData as their generic "device fault" now use SendData
  so their Degraded leg is still exercised.

Refs #742
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
2026-10-22 15:20:51 -04:00