feat(ablegacy): Transport option selects native or libplctag across driver, probe and CLI

src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Cli/AbLegacyCommandBase.cs

@@ -25,6 +25,12 @@ public abstract class AbLegacyCommandBase : DriverCommandBase
         "Slc500 / MicroLogix / Plc5 / LogixPccc (default Slc500).")]
     public AbLegacyPlcFamily PlcType { get; init; } = AbLegacyPlcFamily.Slc500;
 
+    /// <summary>Gets the transport stack used to reach the PLC.</summary>
+    [CommandOption("transport", Description =
+        "Transport stack: libplctag (default) or native (managed EtherNet/IP + PCCC; PLC-5 N-file reads only, " +
+        "no status-bit writes, LogixPccc unverified).")]
+    public AbLegacyTransport Transport { get; init; } = AbLegacyTransport.Libplctag;
+
     /// <summary>Gets the per-operation timeout in milliseconds.</summary>
     [CommandOption("timeout-ms", Description = "Per-operation timeout in ms (default 5000).")]
     public int TimeoutMs { get; init; } = 5000;
@@ -56,6 +62,7 @@ public abstract class AbLegacyCommandBase : DriverCommandBase
         RawTags = [.. tags.Select(t => new RawTagEntry(
             t.Name, AbLegacyTagDefinitionFactory.ToTagConfig(t), t.WriteIdempotent, DeviceName: t.DeviceHostAddress))],
         Timeout = Timeout,
+        Transport = Transport,
         Probe = new AbLegacyProbeOptions { Enabled = false },
     };
 

src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Cli/Program.cs

@@ -5,7 +5,7 @@ return await new CliApplicationBuilder()
     .SetExecutableName("otopcua-ablegacy-cli")
     .SetDescription(
         "OtOpcUa AB Legacy test-client — ad-hoc probe + PCCC N/F/B/L-file reads/writes + " +
-        "polled subscriptions against SLC 500 / MicroLogix / PLC-5 devices via libplctag. " +
+        "polled subscriptions against SLC 500 / MicroLogix / PLC-5 devices via libplctag or the native transport. " +
         "Addresses use PCCC convention: N7:0, F8:0, B3:0/3, L19:0, ST17:0.")
     .Build()
     .RunAsync(args);

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Contracts/AbLegacyDriverOptions.cs

@@ -25,6 +25,16 @@ public sealed class AbLegacyDriverOptions
     /// </summary>
     public IReadOnlyList<RawTagEntry> RawTags { get; init; } = [];
 
+    /// <summary>
+    ///     Which transport stack the driver, its Test Connect probe and the CLI use. Defaults to
+    ///     <see cref="AbLegacyTransport.Libplctag"/>.
+    ///     <para>Changing this takes effect when the driver instance is RECREATED, not on
+    ///     <c>ReinitializeAsync</c>: the tag factory is chosen once in the constructor and held across
+    ///     Shutdown+Initialize. A deploy that changes the driver config stops and respawns the instance
+    ///     (<c>DriverSpawnPlanner</c>, #516), so an operator edit does recreate it.</para>
+    /// </summary>
+    public AbLegacyTransport Transport { get; init; } = AbLegacyTransport.Libplctag;
+
     /// <summary>Gets or sets the probe (connectivity check) options.</summary>
     public AbLegacyProbeOptions Probe { get; init; } = new();
 

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Contracts/AbLegacyTransport.cs

@@ -0,0 +1,17 @@
+namespace ZB.MOM.WW.OtOpcUa.Driver.AbLegacy;
+
+/// <summary>
+///     Which PCCC transport stack an AbLegacy driver instance (and its Test Connect probe / CLI run)
+///     talks to the controller through. Serialises as a STRING in driver config JSON.
+/// </summary>
+public enum AbLegacyTransport
+{
+    /// <summary>The libplctag-backed transport. The default.</summary>
+    Libplctag,
+
+    /// <summary>
+    ///     The native managed EtherNet/IP + PCCC transport. Known gaps: PLC-5 supports N-file reads only,
+    ///     writes to status-bit sub-elements are unsupported, and LogixPccc framing is unverified.
+    /// </summary>
+    Native,
+}

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy/AbLegacyDriver.cs

@@ -68,7 +68,11 @@ public sealed class AbLegacyDriver : IDriver, IReadable, IWritable, ITagDiscover
         ArgumentNullException.ThrowIfNull(options);
         _options = options;
         _driverInstanceId = driverInstanceId;
-        _tagFactory = tagFactory ?? new LibplctagLegacyTagFactory();
+        // Chosen once here and held across ReinitializeAsync (Shutdown+Initialize): a changed
+        // Transport in a reinit config is inert; a deploy recreates the instance instead.
+        _tagFactory = tagFactory ?? (options.Transport == AbLegacyTransport.Native
+            ? new NativeAbLegacyTagFactory()
+            : new LibplctagLegacyTagFactory());
         _logger = logger ?? NullLogger<AbLegacyDriver>.Instance;
         _resolver = new EquipmentTagRefResolver<AbLegacyTagDefinition>(
             r => _tagsByRawPath.TryGetValue(r, out var t) ? t : null);
@@ -85,6 +89,9 @@ public sealed class AbLegacyDriver : IDriver, IReadable, IWritable, ITagDiscover
                 new KeyValuePair<string, object?>(OtOpcUaTelemetry.PollOverrunDriverInstanceTag, driverInstanceId)));
     }
 
+    /// <summary>The tag factory chosen at construction; exposed so tests can pin transport selection.</summary>
+    internal IAbLegacyTagFactory TagFactory => _tagFactory;
+
     /// <summary>Upper bound on the poll-loop failure backoff — adopts the S7-proven 30 s cap fleet-wide (05/STAB-8).</summary>
     private static readonly TimeSpan PollBackoffCap = TimeSpan.FromSeconds(30);
 

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy/AbLegacyDriverFactoryExtensions.cs

@@ -97,6 +97,8 @@ public static class AbLegacyDriverFactoryExtensions
                 ProbeAddress = dto.Probe?.ProbeAddress ?? "S:0",
             },
             Timeout = PositiveTimeoutOrDefault(dto.TimeoutMs, 2_000),
+            Transport = ParseEnum<AbLegacyTransport>(dto.Transport, driverInstanceId, "Transport",
+                fallback: AbLegacyTransport.Libplctag),
         };
 
         return options;
@@ -146,6 +148,11 @@ public static class AbLegacyDriverFactoryExtensions
         /// </summary>
         public int? TimeoutMs { get; init; }
 
+        /// <summary>
+        /// Gets or sets the transport (<c>Libplctag</c> or <c>Native</c>, case-insensitive); absent means Libplctag.
+        /// </summary>
+        public string? Transport { get; init; }
+
         /// <summary>
         /// Gets or sets the list of devices to connect to.
         /// </summary>

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy/AbLegacyDriverProbe.cs

@@ -30,12 +30,12 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.AbLegacy;
 /// </summary>
 public sealed class AbLegacyDriverProbe : IDriverProbe
 {
-    private readonly IAbLegacyTagFactory _tagFactory;
+    private readonly IAbLegacyTagFactory? _tagFactory;
 
     /// <summary>Initializes a new instance of the <see cref="AbLegacyDriverProbe"/> class.</summary>
-    /// <param name="tagFactory">The tag factory used for the PCCC handshake; defaults to the libplctag-backed one.</param>
-    public AbLegacyDriverProbe(IAbLegacyTagFactory? tagFactory = null) =>
-        _tagFactory = tagFactory ?? new LibplctagLegacyTagFactory();
+    /// <param name="tagFactory">The tag factory used for the PCCC handshake; when null the config's
+    ///     <c>Transport</c> selects the native or libplctag-backed one.</param>
+    public AbLegacyDriverProbe(IAbLegacyTagFactory? tagFactory = null) => _tagFactory = tagFactory;
 
     private static readonly JsonSerializerOptions _opts = new()
     {
@@ -106,7 +106,10 @@ public sealed class AbLegacyDriverProbe : IDriverProbe
             TagName: tagName,
             Timeout: timeout);
 
-        var rt = _tagFactory.Create(p);
+        var factory = _tagFactory ?? (opts.Transport == AbLegacyTransport.Native
+            ? new NativeAbLegacyTagFactory()
+            : new LibplctagLegacyTagFactory());
+        var rt = factory.Create(p);
         try
         {
             await rt.InitializeAsync(cts.Token);