Async cancellation hygiene, fire-and-forget observability, retry/shutdown
semantics, and audit-row coverage across 9 modules. Highlights:
Cancellation & lifecycle:
- AuditLog-006: SqliteAuditWriter.Dispose hops to thread pool, escaping the
captured SyncContext that risked sync-over-async deadlock.
- AuditLog-010: SiteAuditTelemetryActor owns a private lifecycle CTS,
threaded through drain paths instead of CancellationToken.None.
- Comm-019: CentralCommunicationActor adds lifecycle CTS for repo calls.
- Host-019: Migration StartupRetry forwards ApplicationStopping so SIGTERM
during the bounded-retry window aborts cleanly.
Cursor / retry / counter correctness:
- AuditLog-004: SiteAuditReconciliationActor's cursor now holds at `since`
when any row's idempotent insert is still being retried (per-EventId
retry counter, MaxPermanentInsertAttempts=5 escape valve with LogCritical
abandon). No more silent abandonment of permanently-failing rows.
- ConfigDB-019: Dropped the catch-and-continue on EnsureLookaheadAsync's
SPLIT loop — by class-doc construction the catch could only mask real
failures and let the next iteration create permanent partition holes.
- HM-017/018: HealthReportSender + CentralHealthReportLoop snapshot
per-interval counters before sending, restore via new
ISiteHealthCollector.AddIntervalCounters on transport failure so counts
aren't silently lost.
Fire-and-forget / shutdown waits:
- InboundAPI-018: AuditWriteMiddleware observes faulted audit-write tasks
via OnlyOnFaulted continuation (Warning log; response unchanged).
- SnF-024: StoreAndForwardService.StopAsync awaits in-flight retry sweep
with a bounded SweepShutdownWaitTimeout (10s).
Leak / refactor:
- Comm-021: SiteStreamGrpcServer.SubscribeInstance wraps Subscribe in its
own try/catch so a throw doesn't leak the relay actor or _activeStreams
entry.
- Comm-022: VERIFIED already-closed by Comm-016's dead-code purge.
- CLI-017: BundleCommands' three subcommands delegate to ExecuteCommandAsync
(auth-failure exit-code contract unified).
Defensive / validation:
- CLI-021: CliConfig.Load wraps file-read/JSON parse so malformed config
prints a warning and returns defaults instead of crashing the CLI.
- Host-022: ParseLevel emits stderr one-shot warning for unrecognised
MinimumLevel instead of silently coercing to Information.
- ESG-019: ExternalSystemClient sets HttpClient.Timeout=Infinite so the
per-call CTS is the sole timeout source (was clipped to 100s by .NET).
- Security-020: New SecurityOptionsValidator (IValidateOptions) rejects
empty LdapServer/LdapSearchBase with ValidateOnStart.
- DM-019: Lifecycle command timeouts now emit DisableTimedOut/EnableTimedOut/
DeleteTimedOut audit entries (mirrors DeployFailed pattern).
Plus reconciled stale per-module Open-findings counters that had drifted
from prior sessions.
20+ new regression tests across 11 test projects; build clean; affected
suites all green. README regenerated: 75 open (was 93).
Comm-016: delete dead HandleConnectionStateChanged + _debugSubscriptions /
_inProgressDeployments tracking + ConnectionStateChanged message record.
Disconnect detection is owned by the transport layers (gRPC keepalive PING
~25s; Ask-timeout at CommunicationService). Updates the
Component-Communication.md design doc to make that explicit.
SnF-018: NotificationForwarder.DeliverAsync now discards a corrupt buffered
payload (Warning log + return true) instead of returning false and parking
the row — honoring the design's "notifications do not park" invariant.
DM-018: reconciliation no longer force-sets Enabled, preserving an
intentional Disabled state after central failover.
ESG-018: DeliverBufferedAsync (both ExternalSystemClient + DatabaseGateway)
catches JsonException and returns false, turning a corrupt buffered row
into a parked operation instead of a retry-forever poison message.
InboundAPI-022: register ActiveNodeGate as IActiveNodeGate in the Central
DI branch so standby-node gating is actually wired up in production.
NS-019: remove orphaned NotificationDeliveryService /
INotificationDeliveryService / NotificationResult; central notification
delivery now lives entirely in NotificationOutbox.
SEL-016: normalise From/To filters to UTC before ISO-string compare so
non-UTC DateTimeOffset clients no longer get spuriously excluded events.
TE-017: include Description on attributes/alarms and a HashableConnections
projection (protocol, endpoint JSON, failover count) in the revision hash
and DiffService; staleness detection now catches description-only and
connection-endpoint edits.
Transport-001 and Transport-002 (also High) remain Open — they're being
handled in a follow-up batch because both touch BundleImporter.cs and
must serialise.
- NodeName: semantic role-within-cluster identifier (node-a/node-b on sites,
central-a/central-b on central). Bound from ScadaLink:Node:NodeName.
- INodeIdentityProvider exposes the trimmed name (null if unconfigured) so
downstream audit writers can stamp the new SourceNode column.
M3 Bundle F (Task F1) wires the cached-call audit pipeline through the
composition roots:
- Central: register SiteCallAuditActor as a cluster singleton + proxy
(mirrors AuditLogIngestActor and NotificationOutboxActor). Program.cs
calls .AddSiteCallAudit() on the central role.
- Site: register ICachedCallTelemetryForwarder + CachedCallLifecycleBridge
in AddAuditLog (lazy factory — Central nodes degrade to audit-only
emission because IOperationTrackingStore is site-only).
- Site: bind CachedCallLifecycleBridge to ICachedCallLifecycleObserver so
StoreAndForwardService picks it up via DI.
- Site: introduce IStoreAndForwardSiteContext + Host adapter to surface the
site id to StoreAndForwardService without creating a
StoreAndForward -> HealthMonitoring project-reference cycle.
- ScriptExecutionActor resolves ICachedCallTelemetryForwarder per script
scope and threads it into ScriptRuntimeContext.
CachedCallTelemetryForwarder's IOperationTrackingStore dependency is now
nullable so Central DI validation succeeds with the lazy registration; the
forwarder's tracking-half emission is a no-op when the store is absent.
Tests:
- AkkaHostedServiceAuditWiringTests: Central host builds with
AddSiteCallAudit and resolves ICachedCallTelemetryForwarder; Site
resolves the forwarder + bridge + observer + IStoreAndForwardSiteContext.
- Full solution: 194 Host tests green, 241 SiteRuntime tests green, every
other suite unchanged.
Bundle G of Audit Log #23 M2. Bridges the FallbackAuditWriter primary-
failure counter into the Site Health Monitoring report payload so a
sustained audit-write outage surfaces on /monitoring/health instead of
disappearing into a NoOp sink.
- SiteHealthReport: add SiteAuditWriteFailures (defaulted, additive).
- ISiteHealthCollector + SiteHealthCollector: new
IncrementSiteAuditWriteFailures() counter, per-interval reset
semantics matching ScriptErrorCount / DeadLetterCount.
- HealthMetricsAuditWriteFailureCounter: adapter forwarding
IAuditWriteFailureCounter.Increment() to the collector.
- AddAuditLogHealthMetricsBridge(): swaps the NoOp default
registration for the real bridge; called from
SiteServiceRegistration after AddSiteHealthMonitoring + AddAuditLog.
- Existing host-wiring test updated: site composition now resolves
HealthMetricsAuditWriteFailureCounter (not NoOp).
Tests: HealthMonitoring 60 -> 63 (3 new), AuditLog 56 -> 59 (3 new),
full solution green.
Wires Bundle E of the M2 site-sync pipeline:
- AddAuditLog extended to register the site writer chain (SqliteAuditWriter
singleton + ISiteAuditQueue forward + RingBufferFallback + FallbackAuditWriter
composing them) and the telemetry collaborators (SiteAuditTelemetryOptions,
SqliteAuditWriterOptions, IAuditWriteFailureCounter NoOp default,
ISiteStreamAuditClient NoOp default).
- AkkaHostedService central role: AuditLogIngestActor as ClusterSingletonManager
(singleton name 'audit-log-ingest') + ClusterSingletonProxy, mirroring the
Notification Outbox pattern. Proxy is offered to SiteStreamGrpcServer if it
resolves (Site path only today; M6 reconciliation will host gRPC on central).
- AkkaHostedService site role: SiteAuditTelemetryActor (per-site, NOT a
singleton because each site is its own cluster), bound to a dedicated
audit-telemetry-dispatcher (ForkJoinDispatcher, 2 dedicated threads).
- Program.cs + SiteServiceRegistration.Configure call AddAuditLog on both roles.
- AuditLogIngestActor gains a second constructor that takes IServiceProvider so
the cluster singleton can create a fresh scope per message — IAuditLogRepository
is a scoped EF Core service and cannot be pre-resolved from the root. The
IAuditLogRepository constructor remains for Bundle D's MSSQL-fixture tests.
NoOp ISiteStreamAuditClient is deliberate: no site→central gRPC channel exists
in M2 (sites talk to central via Akka ClusterClient; gRPC SiteStreamService is
hosted on sites for central→site streaming). M6 reconciliation introduces the
real gRPC site→central client + central-hosted gRPC server. Bundle H's
integration test substitutes a stub client directly via the actor's Props.
Tests:
- tests/ScadaLink.AuditLog.Tests/AddAuditLogTests.cs — 11 tests (was 3): writer
singleton, IAuditWriter as FallbackAuditWriter, ISiteAuditQueue same-instance
as SqliteAuditWriter, options bind round-trip, NoOp default assertions.
- tests/ScadaLink.Host.Tests/AkkaHostedServiceAuditWiringTests.cs (new) — 13
tests: BuildHocon emits audit-telemetry-dispatcher block with the expected
type/throughput/thread-count; Central composition root resolves the writer
chain + options; Site composition root resolves the writer chain + options +
NoOp client.
Verified: dotnet build clean, 23 test suites green (Host 194 + AuditLog 54).
Wire the Notification Outbox into the Host central role:
- Program.cs: call AddNotificationOutbox() on the central path (binds
NotificationOutboxOptions via BindConfiguration; no explicit Configure).
- AkkaHostedService.RegisterCentralActors(): create the NotificationOutboxActor
as a non-role-scoped central cluster singleton + proxy, then send
RegisterNotificationOutbox(proxy) to the CentralCommunicationActor.
- appsettings.Central.json: add the ScadaLink:NotificationOutbox section with
the NotificationOutboxOptions defaults.
- SiteServiceRegistration: remove the now-dead AddNotificationService() call -
sites forward notifications to central rather than delivering over SMTP, and
no site component consumes the SMTP machinery.
- Host.csproj: add the ScadaLink.NotificationOutbox project reference.
- Tests: add central outbox singleton/proxy actor-path assertions, drop the
site OAuth2TokenService/INotificationDeliveryService resolution assertions,
and add NotificationOutbox to the component-library IConfiguration check.
ConfigurationDatabase-012 made ApiKeyHasher fail fast on a missing/weak HMAC
pepper, so resolving ApiKeyValidator from the central composition root now
requires ScadaLink:InboundApi:ApiKeyPepper to be configured. The composition-
root test's in-memory config now supplies a test pepper, like JwtSigningKey.
- DeploymentManager-008: revert IConfiguration overload (violated OptionsTests
component-convention); Host now binds the ScadaLink:DeploymentManager section
- SiteStreamGrpcServer: make test-only int ctor internal so DI sees one public
ctor (resolves ambiguous-constructor failure in SiteCompositionRootTests)
- Host site composition-root test config: supply Cluster:SeedNodes for the new
ClusterOptionsValidator
Move all package versions into Directory.Packages.props so every project
resolves a single consistent version. Consolidates the Roslyn packages
(Microsoft.CodeAnalysis.CSharp.Scripting/Workspaces) onto 5.0.0, which
resolves the pre-existing NU1608 version-skew error in the test projects.
Restore inside the docker build was failing because TreatWarningsAsErrors
promotes NU1902/NU1903/NU1904 (vulnerable package warnings) to errors.
Bump the flagged packages to advisory-free versions:
- MailKit 4.15.1 -> 4.16.0 (GHSA-9j88-vvj5-vhgr)
- Microsoft.AspNetCore.DataProtection.EFCore 10.0.5 -> 10.0.7 (GHSA-9mv3-2cwr-p262, transitively pulls fixed System.Security.Cryptography.Xml — GHSA-37gx-xxp4-5rgx, GHSA-w3x6-4m5h-cxqf)
- OpenTelemetry.Api (transitive via Akka.Hosting) 1.9.0 -> 1.15.3 (GHSA-g94r-2vxg-569j, GHSA-8785-wc3w-h8q6) — added as a direct PackageReference in ScadaLink.Host to override the Akka.Hosting pin
To resolve the NU1605 downgrade chain triggered by DataProtection.EFCore
10.0.7 (which transitively requires Microsoft.EntityFrameworkCore >= 10.0.7
and friends), bump every Microsoft.* 10.0.5 reference across src/ and
tests/ to 10.0.7 in lockstep.
Switch site host to WebApplicationBuilder with Kestrel HTTP/2 gRPC server,
add GrpcPort/keepalive config, wire SiteStreamManager as ISiteStreamSubscriber,
expose gRPC ports in docker-compose, add site seed script, update all 10
requirement docs + CLAUDE.md + README.md for the new dual-transport architecture.
Add ActiveNodeHealthCheck that returns 200 only on the Akka.NET cluster
leader, enabling Traefik to route traffic to the active central node and
automatically fail over when the leader changes. Also fixes AkkaClusterHealthCheck
to resolve ActorSystem from AkkaHostedService (was always null via DI).
IServiceProvider now flows through the actor chain (DeploymentManagerActor
→ InstanceActor → ScriptActor → ScriptExecutionActor) so scripts can
resolve IExternalSystemClient, IDatabaseGateway, and
INotificationDeliveryService from DI. ScriptGlobals exposes ExternalSystem,
Database, Notify, and Scripts as top-level properties so scripts can use
them without the Instance. prefix.
- WP-0.10: Role-based Host startup (Central=WebApplication, Site=generic Host),
15 component AddXxx() extension methods, MapCentralUI/MapInboundAPI stubs
- WP-0.11: 12 per-component options classes with config binding
- WP-0.12: Sample appsettings for central and site topologies
- Add execution procedure and checklist template to generate_plans.md
- Add phase-0-checklist.md for execution tracking
- Resolve all 21 open questions from plan generation
- Update IDataConnection with batch ops and IAsyncDisposable
57 tests pass, zero warnings.
17 source projects (Commons + Host + 15 components) and 17 xUnit test projects.
SLNX format, net10.0, nullable enabled, warnings as errors. All components
reference Commons; Host references all components. Builds and tests clean.
Joseph Doherty