Closes the observer half of #162 that was flagged as "persisted as 0 today"
in PR #105. The Admin /hosts column refresh + FleetStatusHub SignalR push
+ red-badge visual still belong to the visual-compliance pass.
Core.Resilience:
- DriverResilienceStatusTracker gains RecordCallStart + RecordCallComplete
+ CurrentInFlight field on the snapshot record. Concurrent-safe via the
same ConcurrentDictionary.AddOrUpdate pattern as the other recorder methods.
Clamps to zero on over-decrement so a stray Complete-without-Start can't
drive the counter negative.
- CapabilityInvoker gains an optional statusTracker ctor parameter. When
wired, every ExecuteAsync / ExecuteAsync(void) wraps the pipeline call
in try / finally that records start/complete — so the counter advances
cleanly whether the call succeeds, cancels, or throws. Null tracker keeps
the pre-Phase-6.1 Stream E.3 behaviour exactly.
Server.Hosting:
- ResilienceStatusPublisherHostedService persists CurrentInFlight as the
DriverInstanceResilienceStatus.CurrentBulkheadDepth column (was 0 before
this PR). One-line fix on both the insert + update branches.
The in-flight counter is a pragmatic proxy for Polly's internal bulkhead
depth — a future PR wiring Polly telemetry would replace it with the real
value. The shape of the column + the publisher + the Admin /hosts query
doesn't change, so the follow-up is invisible to consumers.
Tests (8 new InFlightCounterTests, all pass):
- Start+Complete nets to zero.
- Nested starts sum; Complete decrements.
- Complete-without-Start clamps to zero.
- Different hosts track independently.
- Concurrent starts (500 parallel) don't lose count.
- CapabilityInvoker observed-mid-call depth == 1 during a pending call.
- CapabilityInvoker exception path still decrements (try/finally).
- CapabilityInvoker without tracker doesn't throw.
Full solution dotnet test: 1243 passing (was 1235, +8). Pre-existing
Client.CLI Subscribe flake unchanged.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Ships the data + runtime layer of Stream E. The SignalR hub and Blazor /hosts
page refresh (E.2-E.3) are follow-up work paired with the visual-compliance
review per Phase 6.4 patterns — documented as a deferred follow-up below.
Configuration:
- New entity DriverInstanceResilienceStatus with:
DriverInstanceId, HostName (composite PK),
LastCircuitBreakerOpenUtc, ConsecutiveFailures, CurrentBulkheadDepth,
LastRecycleUtc, BaselineFootprintBytes, CurrentFootprintBytes,
LastSampledUtc.
- Separate from DriverHostStatus (per-host connectivity view) so a Running
host that has tripped its breaker or is nearing its memory ceiling shows up
distinctly on Admin /hosts. Admin page left-joins both for display.
- OtOpcUaConfigDbContext + Fluent-API config + IX_DriverResilience_LastSampled
index for the stale-sample filter query.
- EF migration: 20260419124034_AddDriverInstanceResilienceStatus.
Core.Resilience:
- DriverResilienceStatusTracker — process-singleton in-memory tracker keyed on
(DriverInstanceId, HostName). CapabilityInvoker + MemoryTracking +
MemoryRecycle callers record failure/success/breaker-open/recycle/footprint
events; a HostedService (Stream E.2 follow-up) samples this tracker every
5 s and persists to the DB. Pure in-memory keeps tests fast + the core
free of EF/SQL dependencies.
Tests:
- DriverResilienceStatusTrackerTests (9 new, all pass): tryget-before-write
returns null; failures accumulate; success resets; breaker/recycle/footprint
fields populate; per-host isolation; snapshot returns all pairs; concurrent
writes don't lose counts.
- SchemaComplianceTests: expected-tables list updated to include the new
DriverInstanceResilienceStatus table.
Full solution dotnet test: 1042 passing (baseline 906, +136 for Phase 6.1 so
far across Streams A/B/C/D/E.1). Pre-existing Client.CLI Subscribe flake
unchanged.
Deferred to follow-up PR (E.2/E.3):
- ResilienceStatusPublisher HostedService that samples DriverResilienceStatusTracker
every 5 s + upserts DriverInstanceResilienceStatus rows.
- Admin FleetStatusHub SignalR hub pushing LastCircuitBreakerOpenUtc /
CurrentBulkheadDepth / LastRecycleUtc on change.
- Admin /hosts Blazor column additions (red badge when
ConsecutiveFailures > breakerThreshold / 2). Visual-compliance reviewer
signoff alongside Phase 6.4 admin-ui patterns.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
