TwinCAT PR 3 — ITagDiscovery + ISubscribable + IHostConnectivityProbe + IPerCallHostResolver. Completes the TwinCAT driver — 7-interface capability set matching AbCip / AbLegacy (minus IAlarmSource, same deferral). ITagDiscovery emits pre-declared tags under TwinCAT/device-host folder with DeviceName fallback to HostAddress; Writable→Operate / non-writable→ViewOnly. Symbol-browsing via AdsClient.ReadSymbolsAsync / ReadSymbolInfoAsync deferred to a follow-up (same shape as the @tags deferral for AbCip — needs careful traversal of the TwinCAT symbol table + type graph which the ReadSymbolsAsync API does expose but adds enough scope to warrant its own PR). ISubscribable consumes the shared PollGroupEngine — 4th consumer after Modbus + AbCip + AbLegacy. TwinCAT supports native ADS notifications (AddDeviceNotification) which would be strictly superior to polling, but plumbing through OPC UA semantics + the PollGroupEngine abstraction would require a parallel sampling path; poll-first matches the cross-driver pattern + gets the driver shippable. Follow-up task for native-notification upgrade tracked after merge. IHostConnectivityProbe — per-device probe loop using ITwinCATClient.ProbeAsync which wraps AdsClient.ReadStateAsync (cheap handshake that returns the target's AdsState, succeeds when router + target both respond). Success transitions to Running, any exception or probe-false to Stopped. Same lazy-connect + dispose-on-failure pattern as the read/write path — device state reconnects cleanly after a transient. IPerCallHostResolver maps tag full-ref to DeviceHostAddress for Phase 6.1 (DriverInstanceId, ResolvedHostName) bulkhead/breaker keying per plan decision #144; unknown refs fall back to first device, no devices → DriverInstanceId. ShutdownAsync disposes PollGroupEngine + cancels/disposes every probe CTS + disposes every cached client. DeviceState extended with ProbeLock / HostState / HostStateChangedUtc / ProbeCts matching AbCip/AbLegacy shape. 10 new tests in TwinCATCapabilityTests — discovery tag emission with correct SecurityClassification, subscription initial poll raises OnDataChange, shutdown cancels subscriptions, GetHostStatuses entry-per-device, probe Running transition on ProbeResult=true, probe Stopped on ProbeResult=false, probe disabled when Enabled=false, ResolveHost for known/unknown/no-devices paths. Total TwinCAT unit tests now 85/85 passing (+10 from PR 2's 75); full solution builds 0 errors; other drivers untouched. TwinCAT driver complete end-to-end — any TC2/TC3 AMS target reachable through a router is now shippable with read/write/discover/subscribe/probe/host-resolve, feature-parity with AbCip/AbLegacy.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-19 18:36:55 -04:00
parent 2d5aaf1eda
commit aeb28cc8e7
2 changed files with 383 additions and 4 deletions
--- a/src/ZB.MOM.WW.OtOpcUa.Driver.TwinCAT/TwinCATDriver.cs
+++ b/src/ZB.MOM.WW.OtOpcUa.Driver.TwinCAT/TwinCATDriver.cs
@@ -7,15 +7,20 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT;
 ///     the <see cref="IDriver"/> skeleton; read / write / discover / subscribe / probe / host-
 ///     resolver land in PRs 2 and 3.
 /// </summary>
-public sealed class TwinCATDriver : IDriver, IReadable, IWritable, IDisposable, IAsyncDisposable
+public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery, ISubscribable,
+    IHostConnectivityProbe, IPerCallHostResolver, IDisposable, IAsyncDisposable
 {
    private readonly TwinCATDriverOptions _options;
    private readonly string _driverInstanceId;
    private readonly ITwinCATClientFactory _clientFactory;
+    private readonly PollGroupEngine _poll;
    private readonly Dictionary<string, DeviceState> _devices = new(StringComparer.OrdinalIgnoreCase);
    private readonly Dictionary<string, TwinCATTagDefinition> _tagsByName = new(StringComparer.OrdinalIgnoreCase);
    private DriverHealth _health = new(DriverState.Unknown, null, null);

+    public event EventHandler<DataChangeEventArgs>? OnDataChange;
+    public event EventHandler<HostStatusChangedEventArgs>? OnHostStatusChanged;
+
    public TwinCATDriver(TwinCATDriverOptions options, string driverInstanceId,
        ITwinCATClientFactory? clientFactory = null)
    {
@@ -23,6 +28,10 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, IDisposable,
        _options = options;
        _driverInstanceId = driverInstanceId;
        _clientFactory = clientFactory ?? new AdsTwinCATClientFactory();
+        _poll = new PollGroupEngine(
+            reader: ReadAsync,
+            onChange: (handle, tagRef, snapshot) =>
+                OnDataChange?.Invoke(this, new DataChangeEventArgs(handle, tagRef, snapshot)));
    }

    public string DriverInstanceId => _driverInstanceId;
@@ -41,6 +50,16 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, IDisposable,
                _devices[device.HostAddress] = new DeviceState(addr, device);
            }
            foreach (var tag in _options.Tags) _tagsByName[tag.Name] = tag;
+
+            if (_options.Probe.Enabled)
+            {
+                foreach (var state in _devices.Values)
+                {
+                    state.ProbeCts = new CancellationTokenSource();
+                    var ct = state.ProbeCts.Token;
+                    _ = Task.Run(() => ProbeLoopAsync(state, ct), ct);
+                }
+            }
            _health = new DriverHealth(DriverState.Healthy, DateTime.UtcNow, null);
        }
        catch (Exception ex)
@@ -57,13 +76,19 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, IDisposable,
        await InitializeAsync(driverConfigJson, cancellationToken).ConfigureAwait(false);
    }

-    public Task ShutdownAsync(CancellationToken cancellationToken)
+    public async Task ShutdownAsync(CancellationToken cancellationToken)
    {
-        foreach (var state in _devices.Values) state.DisposeClient();
+        await _poll.DisposeAsync().ConfigureAwait(false);
+        foreach (var state in _devices.Values)
+        {
+            try { state.ProbeCts?.Cancel(); } catch { }
+            state.ProbeCts?.Dispose();
+            state.ProbeCts = null;
+            state.DisposeClient();
+        }
        _devices.Clear();
        _tagsByName.Clear();
        _health = new DriverHealth(DriverState.Unknown, _health.LastSuccessfulRead, null);
-        return Task.CompletedTask;
    }

    public DriverHealth GetHealth() => _health;
@@ -183,6 +208,100 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, IDisposable,
        return results;
    }

+    // ---- ITagDiscovery ----
+
+    public Task DiscoverAsync(IAddressSpaceBuilder builder, CancellationToken cancellationToken)
+    {
+        ArgumentNullException.ThrowIfNull(builder);
+        var root = builder.Folder("TwinCAT", "TwinCAT");
+        foreach (var device in _options.Devices)
+        {
+            var label = device.DeviceName ?? device.HostAddress;
+            var deviceFolder = root.Folder(device.HostAddress, label);
+            var tagsForDevice = _options.Tags.Where(t =>
+                string.Equals(t.DeviceHostAddress, device.HostAddress, StringComparison.OrdinalIgnoreCase));
+            foreach (var tag in tagsForDevice)
+            {
+                deviceFolder.Variable(tag.Name, tag.Name, new DriverAttributeInfo(
+                    FullName: tag.Name,
+                    DriverDataType: tag.DataType.ToDriverDataType(),
+                    IsArray: false,
+                    ArrayDim: null,
+                    SecurityClass: tag.Writable
+                        ? SecurityClassification.Operate
+                        : SecurityClassification.ViewOnly,
+                    IsHistorized: false,
+                    IsAlarm: false,
+                    WriteIdempotent: tag.WriteIdempotent));
+            }
+        }
+        return Task.CompletedTask;
+    }
+
+    // ---- ISubscribable (polling overlay via shared engine) ----
+
+    public Task<ISubscriptionHandle> SubscribeAsync(
+        IReadOnlyList<string> fullReferences, TimeSpan publishingInterval, CancellationToken cancellationToken) =>
+        Task.FromResult(_poll.Subscribe(fullReferences, publishingInterval));
+
+    public Task UnsubscribeAsync(ISubscriptionHandle handle, CancellationToken cancellationToken)
+    {
+        _poll.Unsubscribe(handle);
+        return Task.CompletedTask;
+    }
+
+    // ---- IHostConnectivityProbe ----
+
+    public IReadOnlyList<HostConnectivityStatus> GetHostStatuses() =>
+        [.. _devices.Values.Select(s => new HostConnectivityStatus(s.Options.HostAddress, s.HostState, s.HostStateChangedUtc))];
+
+    private async Task ProbeLoopAsync(DeviceState state, CancellationToken ct)
+    {
+        while (!ct.IsCancellationRequested)
+        {
+            var success = false;
+            try
+            {
+                var client = await EnsureConnectedAsync(state, ct).ConfigureAwait(false);
+                success = await client.ProbeAsync(ct).ConfigureAwait(false);
+            }
+            catch (OperationCanceledException) when (ct.IsCancellationRequested) { break; }
+            catch
+            {
+                // Probe failure — EnsureConnectedAsync's connect-failure path already disposed
+                // + cleared the client, so next tick will reconnect.
+            }
+
+            TransitionDeviceState(state, success ? HostState.Running : HostState.Stopped);
+
+            try { await Task.Delay(_options.Probe.Interval, ct).ConfigureAwait(false); }
+            catch (OperationCanceledException) { break; }
+        }
+    }
+
+    private void TransitionDeviceState(DeviceState state, HostState newState)
+    {
+        HostState old;
+        lock (state.ProbeLock)
+        {
+            old = state.HostState;
+            if (old == newState) return;
+            state.HostState = newState;
+            state.HostStateChangedUtc = DateTime.UtcNow;
+        }
+        OnHostStatusChanged?.Invoke(this,
+            new HostStatusChangedEventArgs(state.Options.HostAddress, old, newState));
+    }
+
+    // ---- IPerCallHostResolver ----
+
+    public string ResolveHost(string fullReference)
+    {
+        if (_tagsByName.TryGetValue(fullReference, out var def))
+            return def.DeviceHostAddress;
+        return _options.Devices.FirstOrDefault()?.HostAddress ?? DriverInstanceId;
+    }
+
    private async Task<ITwinCATClient> EnsureConnectedAsync(DeviceState device, CancellationToken ct)
    {
        if (device.Client is { IsConnected: true } c) return c;
@@ -210,6 +329,11 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, IDisposable,
        public TwinCATDeviceOptions Options { get; } = options;
        public ITwinCATClient? Client { get; set; }

+        public object ProbeLock { get; } = new();
+        public HostState HostState { get; set; } = HostState.Unknown;
+        public DateTime HostStateChangedUtc { get; set; } = DateTime.UtcNow;
+        public CancellationTokenSource? ProbeCts { get; set; }
+
        public void DisposeClient()
        {
            Client?.Dispose();