Ships the composition kernel that maps Config DB rows (Script / VirtualTag /
ScriptedAlarm) to the runtime definitions VirtualTagEngine + ScriptedAlarmEngine
consume, builds the engine instances, and wires OnEvent → historian-sink routing.
## src/ZB.MOM.WW.OtOpcUa.Server/Phase7/
- CachedTagUpstreamSource — implements both Core.VirtualTags.ITagUpstreamSource and
Core.ScriptedAlarms.ITagUpstreamSource (identical shape, distinct namespaces) on one
concrete type so the composer can hand one instance to both engines. Thread-safe
ConcurrentDictionary value cache with synchronous ReadTag + fire-on-write
Push(path, snapshot) that fans out to every observer registered via SubscribeTag.
Unknown-path reads return a BadNodeIdUnknown-quality snapshot (status 0x80340000)
so scripts branch on quality naturally.
- Phase7EngineComposer.Compose(scripts, virtualTags, scriptedAlarms, upstream,
alarmStateStore, historianSink, rootScriptLogger, loggerFactory) — single static
entry point that:
* Indexes scripts by ScriptId, resolves VirtualTag.ScriptId + ScriptedAlarm.PredicateScriptId
to full SourceCode
* Projects DB rows to VirtualTagDefinition + ScriptedAlarmDefinition (mapping
DataType string → DriverDataType enum, AlarmType string → AlarmKind enum,
Severity 1..1000 → AlarmSeverity bucket matching the OPC UA Part 9 bands
that AbCipAlarmProjection + OpcUaClient MapSeverity already use)
* Constructs VirtualTagEngine + loads definitions (throws InvalidOperationException
with the list of scripts that failed to compile — aggregated like Streams B+C)
* Constructs ScriptedAlarmEngine + loads definitions + wires OnEvent →
IAlarmHistorianSink.EnqueueAsync using ScriptedAlarmEvent.Emission as the event
kind + Condition.LastAckUser/LastAckComment for audit fields
* Returns Phase7ComposedSources with Disposables list the caller owns
Empty Phase 7 config returns Phase7ComposedSources.Empty so deployments without
scripts / alarms behave exactly as pre-Phase-7. Non-null sources flow into
OpcUaApplicationHost's virtualReadable / scriptedAlarmReadable plumbing landed by
task #239 — DriverNodeManager then dispatches reads by NodeSourceKind per PR #186.
## Tests — 12/12
CachedTagUpstreamSourceTests (6):
- Unknown-path read returns BadNodeIdUnknown-quality snapshot
- Push-then-Read returns cached value
- Push fans out to subscribers in registration order
- Push to one path doesn't fire another path's observer
- Dispose of subscription handle stops fan-out
- Satisfies both Core.VirtualTags + Core.ScriptedAlarms ITagUpstreamSource interfaces
Phase7EngineComposerTests (6):
- Empty rows → Phase7ComposedSources.Empty (both sources null)
- VirtualTag rows → VirtualReadable non-null + Disposables populated
- Missing script reference throws InvalidOperationException with the missing ScriptId
in the message
- Disabled VirtualTag row skipped by projection
- TimerIntervalMs → TimeSpan.FromMilliseconds round-trip
- Severity 1..1000 maps to Low/Medium/High/Critical at 250/500/750 boundaries
(matches AbCipAlarmProjection + OpcUaClient.MapSeverity banding)
## Scope — what this PR does NOT do
The composition kernel is the tricky part; the remaining wiring is three narrower
follow-ups that each build on this PR:
- task #244 — driver-bridge feed that populates CachedTagUpstreamSource from live
driver subscriptions. Without this, ctx.GetTag returns BadNodeIdUnknown even when
the driver has a fresh value.
- task #245 — ScriptedAlarmReadable adapter exposing each alarm's current Active
state as IReadable. Phase7EngineComposer.Compose currently returns
ScriptedAlarmReadable=null so reads on Source=ScriptedAlarm variables return
BadNotFound per the ADR-002 "misconfiguration not silent fallback" signal.
- task #246 — Program.cs call to Phase7EngineComposer.Compose with config rows
loaded from the sealed-cache DB read, plus SqliteStoreAndForwardSink lifecycle
wiring at %ProgramData%/OtOpcUa/alarm-historian-queue.db with the Galaxy.Host
IPC writer from Stream D.
Task #240 (live OPC UA E2E smoke) depends on all three follow-ups landing.