Adds the worker-side IPC surface for the alarm subsystem so the gateway
can drive the AlarmDispatcher across the named-pipe boundary. Adds four
proto MxCommandKind values + matching command messages and two
MxCommandReply payload variants:
- SubscribeAlarmsCommand(subscription_expression)
- UnsubscribeAlarmsCommand
- AcknowledgeAlarmCommand(alarm_guid, comment, operator_user/node/domain/full_name)
- QueryActiveAlarmsCommand(alarm_filter_prefix)
- AcknowledgeAlarmReplyPayload(native_status)
- QueryActiveAlarmsReplyPayload(repeated ActiveAlarmSnapshot snapshots)
Worker plumbing:
- New IAlarmCommandHandler interface + AlarmCommandHandler production
impl. Lazy-creates an AlarmDispatcher (with a wnwrap-backed consumer
by default) on the first SubscribeAlarms; routes Acknowledge / QueryActive /
Unsubscribe through it. Idempotent under repeated Unsubscribe; rejects
a second Subscribe without an intervening Unsubscribe; cleans up the
consumer if the underlying Subscribe call throws.
- MxAccessCommandExecutor: 4 new switch arms map MxCommandKind values to
IAlarmCommandHandler calls. Acknowledge surfaces the AVEVA native
status into both MxCommandReply.Hresult and the dedicated
AcknowledgeAlarmReplyPayload.NativeStatus so gateway-side consumers
can echo it without unpacking the outer envelope. Invalid GUIDs and
missing payloads return InvalidRequest; handler exceptions return
MxaccessFailure with the exception message in DiagnosticMessage.
- MxAccessStaSession: new constructor overload accepts an
alarmCommandHandlerFactory; it's invoked on the STA thread during
StartAsync and the resulting handler is passed into the executor.
ShutdownGracefullyAsync + Dispose tear it down on the STA before the
data-side cleanup runs.
Tests: 20 new unit tests covering AlarmCommandHandler lazy lifecycle
(Subscribe/Unsubscribe/Acknowledge/Query/Dispose, error paths) and the
executor's 4 alarm switch arms (OK/InvalidRequest/MxaccessFailure paths,
hresult propagation, prefix filtering). Worker test suite total: 192
passed / 3 skipped (live probes) / 1 pre-existing structure-test fail
(untouched).
Deferred to next slice: gateway-side WorkerAlarmRpcDispatcher that
replaces NotWiredAlarmRpcDispatcher, builds + sends these commands across
the IPC, and unwraps the resulting MxCommandReply into AcknowledgeAlarmReply
/ ActiveAlarmSnapshot stream.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
First PR of the alarms-over-gateway epic
(docs/plans/alarms-over-gateway.md in lmxopcua). Pure contract-surface
change — no functional wiring yet. Worker-side subscription (A.2),
gateway-side dispatch + ack handler (A.3), and ConditionRefresh
(A.4) follow.
mxaccess_gateway.proto:
- Extend MxEventFamily with MX_EVENT_FAMILY_ON_ALARM_TRANSITION = 5.
- Extend MxEvent.body oneof with OnAlarmTransitionEvent on_alarm_transition = 24.
- Add OnAlarmTransitionEvent message carrying the full MxAccess alarm
payload (full reference, source object, alarm-type-name, transition
kind, raw severity, original raise timestamp, transition timestamp,
operator user/comment, category, description, current/limit value).
Mapping to OPC UA 0-1000 severity ladder happens server-side in
lmxopcua's MxAccessSeverityMapper (B.1) — gateway preserves the
native MxAccess scale.
- Add AlarmTransitionKind enum (Raise / Acknowledge / Clear / Retrigger).
- Add ActiveAlarmSnapshot + AlarmConditionState for the
ConditionRefresh stream.
- Add public RPCs AcknowledgeAlarm (unary) and QueryActiveAlarms
(server-streaming) on MxAccessGateway service.
- Add AcknowledgeAlarmRequest/Reply + QueryActiveAlarmsRequest.
GatewayContractInfo.GatewayProtocolVersion bumps 2 -> 3. Fixture
manifests (proto-inputs, behavior, parity, golden OpenSessionReply)
and protoset descriptor regenerated.
Tests: round-trip serialization for the new messages with
all-fields-populated and empty-optional-fields cases; oneof
last-write-wins guard between OnDataChange and OnAlarmTransition;
descriptor service-method enumeration includes the two new RPCs.
All 273 existing tests still pass.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Joseph Doherty