Files
ScadaBridge/src/ZB.MOM.WW.ScadaBridge.SiteRuntime/Streaming/SiteStreamAlarmDropReporter.cs
T
Joseph Doherty a212283104 perf(misc): cached hot-path lookups, bounded observer queue, alarm-priority stream path
WP2.6 (arch-review remediation, cross-cutting misc):
- SiteExternalSystemRepository: name/ID-indexed ExternalSystemDefinitionCache replaces
  the fetch-all + reverse-map scan on every by-ID/method lookup; loaded once per
  redeploy, invalidated by DeploymentManagerActor after HandleDeployArtifacts applies
  external-system changes. Static JsonSerializerOptions for method-list parsing.
- Inbound API: short-TTL ApiMethodCache fronts the per-request ApiMethod repository
  fetch; invalidated by name via the existing ScriptArtifactChangeSubscriber/
  IScriptArtifactChangeBus pipeline, self-healing via TTL for changes the bus
  doesn't cover (e.g. Management API edits).
- StoreAndForward: the cached-call audit-observer queue — the one unbounded channel
  left in the system — is now bounded (ObserverQueueCapacity, default 10,000) with
  DropOldest overflow and a dropped-notification counter.
- SiteStreamManager: alarm state changes now travel a dedicated publish
  source/broadcast hub, isolated from the (far higher-volume) attribute path, so an
  attribute storm can no longer evict a pending alarm transition; the alarm hand-off
  queue is bounded with a drop counter surfaced on the site health report
  (SiteStreamAlarmDropCount via the new SiteStreamAlarmDropReporter), and publishing
  is skipped entirely at zero subscribers on either path.
- CLI ManagementHttpClient: explicit 30s HttpClient.Timeout on the shared
  construction (was the 100s framework default), overridable via
  SCADABRIDGE_HTTP_TIMEOUT_SECONDS.

Deviation: the failback-probe heartbeat item is NOT included — its only viable
surface (CentralChannelProvider.cs / heartbeat consumers) lives entirely in the
Communication project, explicitly off-limits to this work package this phase.

Tests: SiteRuntime.Tests (550), InboundAPI.Tests (278), StoreAndForward.Tests (133),
CLI.Tests (390), HealthMonitoring.Tests (97) — all green after full solution build.
2026-08-14 20:59:43 -04:00

79 lines
3.3 KiB
C#

using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using ZB.MOM.WW.ScadaBridge.HealthMonitoring;
namespace ZB.MOM.WW.ScadaBridge.SiteRuntime.Streaming;
/// <summary>
/// WP2.6d (arch-review misc — site stream alarm-vs-attribute shared buffer): site-side
/// hosted service that periodically reads <see cref="SiteStreamManager.AlarmPublishDroppedCount"/>
/// and pushes it into <see cref="ISiteHealthCollector.SetSiteStreamAlarmDropCount"/> so
/// the next <see cref="ISiteHealthCollector.CollectReport"/> carries a fresh snapshot on
/// the site health report. Mirrors <c>ScriptSchedulerStatsReporter</c>: immediate first
/// probe, fixed cadence, exceptions logged and swallowed so the loop survives every probe
/// failure.
/// </summary>
public sealed class SiteStreamAlarmDropReporter : BackgroundService
{
/// <summary>Default poll cadence (10 s) — coarse enough to amortise across health reports.</summary>
internal static readonly TimeSpan DefaultPollInterval = TimeSpan.FromSeconds(10);
private readonly ISiteHealthCollector _collector;
private readonly SiteStreamManager _streamManager;
private readonly ILogger<SiteStreamAlarmDropReporter> _logger;
private readonly TimeSpan _pollInterval;
/// <summary>Initializes a new instance of <see cref="SiteStreamAlarmDropReporter"/>.</summary>
/// <param name="collector">The site health collector that receives the drop count.</param>
/// <param name="streamManager">The site stream manager whose alarm-queue drop count is sampled.</param>
/// <param name="logger">Logger instance.</param>
/// <param name="pollInterval">Poll interval override; defaults to <see cref="DefaultPollInterval"/> (10 s).</param>
public SiteStreamAlarmDropReporter(
ISiteHealthCollector collector,
SiteStreamManager streamManager,
ILogger<SiteStreamAlarmDropReporter> logger,
TimeSpan? pollInterval = null)
{
_collector = collector ?? throw new ArgumentNullException(nameof(collector));
_streamManager = streamManager ?? throw new ArgumentNullException(nameof(streamManager));
_logger = logger ?? throw new ArgumentNullException(nameof(logger));
_pollInterval = pollInterval ?? DefaultPollInterval;
}
/// <inheritdoc />
protected override async Task ExecuteAsync(CancellationToken stoppingToken)
{
// Immediate first probe so the first health report after start carries a
// real snapshot instead of a zero.
Probe();
while (!stoppingToken.IsCancellationRequested)
{
try
{
await Task.Delay(_pollInterval, stoppingToken).ConfigureAwait(false);
}
catch (OperationCanceledException)
{
break;
}
Probe();
}
}
private void Probe()
{
try
{
_collector.SetSiteStreamAlarmDropCount(_streamManager.AlarmPublishDroppedCount);
}
catch (Exception ex)
{
// Catch-all is deliberate: the hosted service must survive every class
// of probe failure so the next tick gets a chance.
_logger.LogWarning(ex, "SiteStreamAlarmDropReporter probe failed; next tick will retry.");
}
}
}