SdkAlarmHistorianWriteBackend.WriteBatchAsync replaces the RetryPlease
placeholder with the real entry point — HistorianAccess.AddStreamedValue
(HistorianEvent, out HistorianAccessError) in aahClientManaged, pinned by
decompiling the installed SDK.
The write path opens its own ReadOnly=false connection: the query-side
HistorianDataSource opens ReadOnly sessions and AddStreamedValue fails on
those with WriteToReadOnlyFile. IHistorianConnectionFactory gains a readOnly
parameter (default true, query path unchanged); BuildConnectionArgs is
extracted as a pure helper. HistorianClusterEndpointPicker is shared for
node failover; connection-class errors abort the batch as RetryPlease and
reset the connection, malformed-input codes map to PermanentFail.
Tests: connection-unavailable batch deferral, ClassifyOutcome error-code
table, BuildConnectionArgs read-vs-write shaping (80 pass, 2 rig-skipped).
Live_* round-trip tests stay Skip-gated for the D.1 rollout smoke.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Produces docs/plans/ entries for tasks #13, #15, #16, and #17-#20:
- phase-6-3-redundancy-interop-plan.md: automation boundary analysis,
concrete test matrix (A/B/C blocks), and a step-by-step cutover
runbook for the deferred Stream F client interop work
- v2-ga-lab-gates-plan.md: exact gate list with command, pass criterion,
and owner for each of the nine v2 GA exit criteria
- live-hardware-validation-runbooks.md: one runbook per driver (FOCAS
CNC smoke #54, AB CIP live-boot, TwinCAT wire-live) with preconditions,
procedure, expected results, and recording template
- alarms-worker-wiring-plan.md: focused plan for A.2/A.3-A.4/C.1/D.1
worker wiring in the mxaccessgw sibling repo, documenting the
discovered AVEVA API surface, the architectural decision that blocks
A.2, the dependency order, and what each item needs to unblock
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
