feat(twincat): native ADS notifications for array tags, decoded from raw bytes

An array tag subscribed natively used to register only its declared scalar
(publishing element 0 at Good) and was then refused wholesale with
BadTypeMismatch. The driver now hands the authored ArrayLength to the client,
which registers the whole array as raw bytes and decodes every notification.

- TwinCATTypeGuard.CheckArray plans the layout from the RESOLVED array type:
  element checked like a scalar notification (width / float kind / string
  kind); STRING(n)/WSTRING(n) elements stride n+1 / 2(n+1); multi-dim arrays
  flattened in PLC memory order; an authored ArrayLength shorter than the PLC
  array reads the leading sub-range, a longer one is refused; struct / pointer
  / nested-array elements, non-array symbols and VAR_IN_OUT refs are refused.
- CheckNotificationSize caps a native array at 128 KiB (largest registration
  proven on a live TC 2.11 target); above it the tag is refused BadOutOfRange.
- TwinCATArrayCodec decodes the bytes into the element-typed CLR array.
- The poll read uses the same plan + codec instead of the Beckhoff typed array
  read, which failed live for most real arrays (exact CLR element type, rank-N
  for multi-dim, member arrays sliced by the under-reported TC2 symbol size).
- TwinCATNotificationRefusedException carries the refusal's status; the type
  mismatch derives from it and the driver isolates either per tag.
This commit is contained in:
Joseph Doherty
2026-10-07 14:45:35 -04:00
parent 9dbaa6d758
commit dcc35f3481
11 changed files with 773 additions and 63 deletions
@@ -107,31 +107,29 @@ internal sealed class AdsTwinCATClient : ITwinCATClient
return (ExtractBit(parentResult.Value, bit), TwinCATStatusMapper.Good);
}
// Array read — ADS reads array symbols natively into a typed managed array. We ask
// the SDK for the element-CLR-type's 1-D array (e.g. int[]); the .NET binding
// marshals the whole array in one read. The returned value is already the boxed
// element-typed array (int[] / float[] / bool[] / string[] / …), so the runtime's
// OPC UA layer sees a proper 1-D array value. ASSUMPTION (no live ADS here):
// AdsClient.ReadValueAsync(symbol, elementType.MakeArrayType(), ct) returns the
// typed array — this matches Beckhoff's documented generic ReadValue<T[]> surface
// (InfoSys tcadsnetref / SumRead samples). Verified only against the fake client.
if (arrayCount is int count && count > 0)
{
var elementType = MapToClrType(type);
var arrayType = elementType.MakeArrayType();
var arrResult = await _client.ReadValueAsync(symbolPath, arrayType, cancellationToken)
.ConfigureAwait(false);
if (arrResult.ErrorCode != AdsErrorCode.NoError)
return (null, MapAndSignal((uint)arrResult.ErrorCode));
return (arrResult.Value, TwinCATStatusMapper.Good);
}
// Scalar read: check the declared type against the PLC symbol first. The symbol is
// Resolve the PLC symbol first so the declared type can be checked against it. The symbol is
// resolved through the Beckhoff symbol cache (the same lookup ReadValueAsync makes
// internally), so this costs no extra round trip after the first read.
var (shape, symbol, symbolStatus) = await DescribeSymbolAsync(symbolPath, cancellationToken)
var (shape, array, symbol, symbolStatus) = await DescribeSymbolAsync(symbolPath, cancellationToken)
.ConfigureAwait(false);
if (symbolStatus != TwinCATStatusMapper.Good) return (null, symbolStatus);
// Array read: raw bytes at the layout TwinCATTypeGuard.CheckArray plans from the RESOLVED
// array type, decoded by TwinCATArrayCodec — the same decode a native array notification
// runs, so poll and notification publish identical arrays. The Beckhoff typed array read this
// replaced failed for most arrays on a live TC 2.11 target: the CLR element type had to match
// exactly (ARRAY OF TIME as uint[] threw), a multi-dimensional array needed a rank-N CLR
// array, and a member array was sliced by its under-reported symbol size.
if (arrayCount is int count)
{
if (TwinCATTypeGuard.CheckArray(type, count, shape, array, out var layout) is not null)
return (null, TwinCATStatusMapper.BadTypeMismatch);
var (arrayBytes, arrayStatus) = await ReadRawAsync(symbolPath, symbol!, layout.ByteLength, cancellationToken)
.ConfigureAwait(false);
return arrayStatus == TwinCATStatusMapper.Good
? (TwinCATArrayCodec.Decode(type, arrayBytes, layout, StringsAreUtf8()), TwinCATStatusMapper.Good)
: (null, arrayStatus);
}
if (TwinCATTypeGuard.CheckRead(type, shape) is not null)
return (null, TwinCATStatusMapper.BadTypeMismatch);
@@ -170,21 +168,34 @@ internal sealed class AdsTwinCATClient : ITwinCATClient
/// <see cref="TwinCATTypeGuard"/> compares a declared type against. Uses the Beckhoff symbol
/// cache (lookup on), so repeat calls are local.
/// </summary>
private async Task<(TwinCATPlcSymbolShape shape, IAdsSymbol? symbol, uint status)> DescribeSymbolAsync(
string symbolPath, CancellationToken cancellationToken)
private async Task<(TwinCATPlcSymbolShape shape, TwinCATPlcArrayShape? array, IAdsSymbol? symbol, uint status)>
DescribeSymbolAsync(string symbolPath, CancellationToken cancellationToken)
{
var result = await _client.ReadSymbolAsync(symbolPath, cancellationToken).ConfigureAwait(false);
if (result.ErrorCode != AdsErrorCode.NoError)
return (default, null, MapAndSignal((uint)result.ErrorCode));
return (default, null, null, MapAndSignal((uint)result.ErrorCode));
if (result.Value is not { } symbol)
return (default, null, TwinCATStatusMapper.BadNodeIdUnknown);
return (default, null, null, TwinCATStatusMapper.BadNodeIdUnknown);
// Resolve aliases (T_MaxString → STRING(255)) so the guard sees the base type, and take the
// resolved type's byte size — a TwinCAT 2 member symbol's own ByteSize is under-reported.
var dataType = symbol.DataType?.Resolve();
var shape = TwinCATPlcSymbolShape.Classify(
dataType?.Name ?? symbol.TypeName, dataType?.Category, symbol.ByteSize, dataType?.ByteSize, symbol.TypeName);
return (shape, symbol, TwinCATStatusMapper.Good);
return (shape, DescribeArray(dataType), symbol, TwinCATStatusMapper.Good);
}
/// <summary>
/// The array facts <see cref="TwinCATTypeGuard.CheckArray"/> plans from: every dimension's element
/// count, the resolved array size, and the alias-resolved element type. Null for a non-array.
/// </summary>
private static TwinCATPlcArrayShape? DescribeArray(IDataType? dataType)
{
if (dataType is not IArrayType arrayType || arrayType.Dimensions is not { } dims) return null;
var element = arrayType.ElementType?.Resolve();
var elementShape = TwinCATPlcSymbolShape.Classify(
element?.Name ?? arrayType.ElementTypeName, element?.Category, element?.ByteSize ?? 0);
return new TwinCATPlcArrayShape([.. dims.Select(d => d.ElementCount)], dataType.ByteSize, elementShape);
}
/// <summary>
@@ -297,6 +308,7 @@ internal sealed class AdsTwinCATClient : ITwinCATClient
string symbolPath,
TwinCATDataType type,
int? bitIndex,
int? arrayCount,
TimeSpan cycleTime,
int maxDelayMs,
Action<string, object?> onChange,
@@ -305,24 +317,42 @@ internal sealed class AdsTwinCATClient : ITwinCATClient
var clrType = MapToClrType(type);
int[]? anyTypeArgs = null;
var stringsUtf8 = false;
TwinCATArrayLayout? arrayLayout = null;
if (bitIndex is null || type != TwinCATDataType.Bool)
{
// A notification carries raw bytes decoded as the DECLARED type, so a declared type that
// cannot decode the PLC symbol (width, float/integer or string kind differ) would publish
// wrong values at Good. Refuse it here; the driver isolates the one tag to Bad.
var (shape, _, symbolStatus) = await DescribeSymbolAsync(symbolPath, cancellationToken)
var (shape, array, _, symbolStatus) = await DescribeSymbolAsync(symbolPath, cancellationToken)
.ConfigureAwait(false);
if (symbolStatus != TwinCATStatusMapper.Good)
throw new InvalidOperationException(
$"Resolving {symbolPath} for a notification failed with status 0x{symbolStatus:X8}");
if (TwinCATTypeGuard.CheckNotification(type, shape) is { } reason)
if (arrayCount is int count)
{
// An array registers the whole planned layout (element stride × authored length, from the
// RESOLVED array type) as raw bytes and decodes it in OnAdsNotificationEx with the same
// TwinCATArrayCodec a poll read uses — so both paths publish the identical array.
if (TwinCATTypeGuard.CheckArray(type, count, shape, array, out var layout) is { } arrayReason)
throw new TwinCATTypeMismatchException(symbolPath, arrayReason);
if (TwinCATTypeGuard.CheckNotificationSize(layout) is { } sizeReason)
throw new TwinCATNotificationRefusedException(symbolPath, sizeReason, TwinCATStatusMapper.BadOutOfRange);
clrType = typeof(byte[]);
anyTypeArgs = [layout.ByteLength];
stringsUtf8 = StringsAreUtf8();
arrayLayout = layout;
}
else if (TwinCATTypeGuard.CheckNotification(type, shape) is { } reason)
{
throw new TwinCATTypeMismatchException(symbolPath, reason);
}
// A string has no fixed width: the "any" type string needs an explicit length (the
// Beckhoff marshaller throws ArgumentNullException without one), and a STRING(n) is n+1
// bytes with n chosen per declaration. Register the PLC's own byte width as raw bytes
// and decode them in OnAdsNotificationEx with the same rules as a read.
if (type is TwinCATDataType.String or TwinCATDataType.WString)
if (arrayLayout is null && type is TwinCATDataType.String or TwinCATDataType.WString)
{
clrType = typeof(byte[]);
anyTypeArgs = [shape.ByteSize];
@@ -346,6 +376,7 @@ internal sealed class AdsTwinCATClient : ITwinCATClient
var reg = new NotificationRegistration(symbolPath, type, bitIndex, onChange, this, result.Handle)
{
StringsUtf8 = stringsUtf8,
ArrayLayout = arrayLayout,
};
_notifications[result.Handle] = reg;
return reg;
@@ -363,6 +394,11 @@ internal sealed class AdsTwinCATClient : ITwinCATClient
var value = args.Value;
if (reg.BitIndex is int bit && reg.Type == TwinCATDataType.Bool && value is not bool)
value = ExtractBit(value, bit);
else if (reg.ArrayLayout is { } layout && value is byte[] arrayBytes)
{
try { value = TwinCATArrayCodec.Decode(reg.Type, arrayBytes, layout, reg.StringsUtf8); }
catch (ArgumentException) { return; } // a short buffer is never published as a short array
}
else if (value is byte[] raw && reg.Type is TwinCATDataType.String or TwinCATDataType.WString)
value = DecodeString(reg.Type, raw, reg.StringsUtf8);
_notificationQueue.Writer.TryWrite(new PendingNotification(reg, value));
@@ -615,6 +651,11 @@ internal sealed class AdsTwinCATClient : ITwinCATClient
/// </summary>
public bool StringsUtf8 { get; init; }
/// <summary>
/// Gets the raw-bytes layout of an array notification, decoded by <see cref="TwinCATArrayCodec"/>; null for a scalar.
/// </summary>
public TwinCATArrayLayout? ArrayLayout { get; init; }
/// <summary>
/// Disposes the notification subscription.
/// </summary>
@@ -41,9 +41,11 @@ public interface ITwinCATClient : IDisposable
/// <param name="symbolPath">The ADS symbol path.</param>
/// <param name="type">The target data type.</param>
/// <param name="bitIndex">Optional bit index for bit extraction within a word.</param>
/// <param name="arrayCount">When non-null, read a 1-D array of this many <paramref name="type"/>
/// elements; the boxed value is the element-typed CLR array (<c>int[]</c> / <c>float[]</c> /
/// <c>bool[]</c> / <c>string[]</c> / …). When null, read a scalar (Phase 4c).</param>
/// <param name="arrayCount">When non-null, read an array of this many <paramref name="type"/>
/// elements (a multi-dimensional PLC array flattened in memory order; a count shorter than the PLC
/// array reads its leading sub-range); the boxed value is the element-typed CLR array
/// (<c>int[]</c> / <c>float[]</c> / <c>bool[]</c> / <c>string[]</c> / …) decoded by
/// <see cref="TwinCATArrayCodec"/>. When null, read a scalar.</param>
/// <param name="cancellationToken">Cancellation token for the read operation.</param>
/// <returns>The boxed value read (or <c>null</c>) together with the mapped OPC UA status.</returns>
Task<(object? value, uint status)> ReadValueAsync(
@@ -87,6 +89,10 @@ public interface ITwinCATClient : IDisposable
/// <param name="symbolPath">ADS symbol path (e.g. <c>MAIN.bStart</c>).</param>
/// <param name="type">Declared type; drives the native layout + callback value boxing.</param>
/// <param name="bitIndex">For BOOL-within-word tags — the bit to extract from the parent word.</param>
/// <param name="arrayCount">When non-null (and no <paramref name="bitIndex"/>), register the whole
/// array: <paramref name="arrayCount"/> elements of <paramref name="type"/> as raw bytes, decoded per
/// notification into the same element-typed CLR array <see cref="ReadValueAsync"/> returns
/// (<see cref="TwinCATArrayCodec"/>). Null = a scalar.</param>
/// <param name="cycleTime">Minimum interval between change notifications (native-floor depends on target).</param>
/// <param name="maxDelayMs">Maximum batching delay in milliseconds — TwinCAT may coalesce
/// notifications up to this delay before pushing them. <c>0</c> = no batching, push
@@ -94,13 +100,18 @@ public interface ITwinCATClient : IDisposable
/// <param name="onChange">Invoked with <c>(symbolPath, boxedValue)</c> per notification.</param>
/// <param name="cancellationToken">Cancels the initial registration; does not tear down an established notification.</param>
/// <returns>A handle whose disposal tears the registered notification down.</returns>
/// <exception cref="TwinCATTypeMismatchException">The declared <paramref name="type"/> cannot decode
/// the PLC symbol (width, float/integer or string kind differ) — the caller isolates that one tag
/// to Bad rather than registering a notification that would publish wrong bytes at Good.</exception>
/// <exception cref="TwinCATNotificationRefusedException">The notification is refused for this one tag
/// — the declared <paramref name="type"/> / <paramref name="arrayCount"/> cannot decode the PLC
/// symbol (<see cref="TwinCATTypeMismatchException"/>: width, float/integer or string kind differ,
/// not an array, too long), or the array exceeds
/// <see cref="TwinCATTypeGuard.MaxNotificationArrayBytes"/>. The caller isolates that one tag to the
/// exception's status rather than registering a notification that would publish wrong bytes at
/// Good.</exception>
Task<ITwinCATNotificationHandle> AddNotificationAsync(
string symbolPath,
TwinCATDataType type,
int? bitIndex,
int? arrayCount,
TimeSpan cycleTime,
int maxDelayMs,
Action<string, object?> onChange,
@@ -0,0 +1,125 @@
using System.Buffers.Binary;
namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT;
/// <summary>
/// Decodes a PLC array's raw bytes — laid out by <see cref="TwinCATTypeGuard.CheckArray"/> — into the
/// element-typed CLR array an array tag publishes (<c>bool[]</c>, <c>short[]</c>, <c>float[]</c>,
/// <c>string[]</c>, …). Both the poll read and the native notification decode here, so the two paths
/// publish identical values, element type and length by construction.
/// </summary>
/// <remarks>
/// The driver reads arrays as raw bytes rather than through the Beckhoff typed array read, which a live
/// TwinCAT 2.11 target showed failing for most real arrays (2026-10-07, Elma cleaner Z33856): the CLR
/// element type had to match the PLC's exactly (<c>ARRAY OF TIME</c> as <c>uint[]</c> threw), a
/// multi-dimensional array demanded a rank-N CLR array, and a dotted MEMBER array was sliced by the
/// under-reported symbol size (<c>ArgumentOutOfRangeException</c>). Elements are little-endian (every
/// TwinCAT target is x86/x64/ARM-LE); a STRING / WSTRING element is decoded by
/// <see cref="TwinCATStringCodec"/> within its fixed stride, so each ends at its own first NUL.
/// </remarks>
internal static class TwinCATArrayCodec
{
/// <summary>Decodes <paramref name="layout"/>.ElementCount elements of <paramref name="declared"/>.</summary>
/// <param name="declared">The tag's declared element type.</param>
/// <param name="bytes">The PLC bytes from the array's first element (at least <see cref="TwinCATArrayLayout.ByteLength"/>).</param>
/// <param name="layout">The planned layout.</param>
/// <param name="utf8">True when the target reports UTF-8 STRING data (else Windows-1252).</param>
/// <returns>The element-typed CLR array.</returns>
/// <exception cref="ArgumentException">The buffer is shorter than the layout.</exception>
public static Array Decode(TwinCATDataType declared, ReadOnlySpan<byte> bytes, TwinCATArrayLayout layout, bool utf8)
{
if (layout.ElementCount < 0 || layout.Stride <= 0 || bytes.Length < layout.ByteLength)
throw new ArgumentException(
$"An array buffer of {bytes.Length} B cannot hold {layout.ElementCount} × {layout.Stride} B elements",
nameof(bytes));
var n = layout.ElementCount;
var stride = layout.Stride;
switch (declared)
{
case TwinCATDataType.Bool:
{
var a = new bool[n];
for (var i = 0; i < n; i++) a[i] = bytes[i * stride] != 0;
return a;
}
case TwinCATDataType.SInt:
{
var a = new sbyte[n];
for (var i = 0; i < n; i++) a[i] = unchecked((sbyte)bytes[i * stride]);
return a;
}
case TwinCATDataType.USInt:
{
var a = new byte[n];
for (var i = 0; i < n; i++) a[i] = bytes[i * stride];
return a;
}
case TwinCATDataType.Int:
{
var a = new short[n];
for (var i = 0; i < n; i++) a[i] = BinaryPrimitives.ReadInt16LittleEndian(bytes[(i * stride)..]);
return a;
}
case TwinCATDataType.UInt:
{
var a = new ushort[n];
for (var i = 0; i < n; i++) a[i] = BinaryPrimitives.ReadUInt16LittleEndian(bytes[(i * stride)..]);
return a;
}
case TwinCATDataType.DInt:
{
var a = new int[n];
for (var i = 0; i < n; i++) a[i] = BinaryPrimitives.ReadInt32LittleEndian(bytes[(i * stride)..]);
return a;
}
case TwinCATDataType.UDInt or TwinCATDataType.Time or TwinCATDataType.Date
or TwinCATDataType.DateTime or TwinCATDataType.TimeOfDay:
{
// TIME / DATE / DT / TOD publish their raw 32-bit count — the same CLR shape (uint) a
// scalar of those types publishes.
var a = new uint[n];
for (var i = 0; i < n; i++) a[i] = BinaryPrimitives.ReadUInt32LittleEndian(bytes[(i * stride)..]);
return a;
}
case TwinCATDataType.LInt:
{
var a = new long[n];
for (var i = 0; i < n; i++) a[i] = BinaryPrimitives.ReadInt64LittleEndian(bytes[(i * stride)..]);
return a;
}
case TwinCATDataType.ULInt:
{
var a = new ulong[n];
for (var i = 0; i < n; i++) a[i] = BinaryPrimitives.ReadUInt64LittleEndian(bytes[(i * stride)..]);
return a;
}
case TwinCATDataType.Real:
{
var a = new float[n];
for (var i = 0; i < n; i++) a[i] = BinaryPrimitives.ReadSingleLittleEndian(bytes[(i * stride)..]);
return a;
}
case TwinCATDataType.LReal:
{
var a = new double[n];
for (var i = 0; i < n; i++) a[i] = BinaryPrimitives.ReadDoubleLittleEndian(bytes[(i * stride)..]);
return a;
}
case TwinCATDataType.String:
{
var a = new string[n];
for (var i = 0; i < n; i++) a[i] = TwinCATStringCodec.DecodeString(bytes.Slice(i * stride, stride), utf8);
return a;
}
case TwinCATDataType.WString:
{
var a = new string[n];
for (var i = 0; i < n; i++) a[i] = TwinCATStringCodec.DecodeWString(bytes.Slice(i * stride, stride));
return a;
}
default:
throw new NotSupportedException($"TwinCATDataType {declared} has no array element decoding");
}
}
}
@@ -279,7 +279,8 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery
if (status == TwinCATStatusMapper.BadTypeMismatch)
_logger.LogWarning(
"TwinCAT driver '{DriverInstanceId}' refused '{Reference}': declared {DataType} " +
"cannot decode the PLC symbol '{Symbol}' (string/numeric kind mismatch or a reference/container)",
"cannot decode the PLC symbol '{Symbol}' (string/numeric kind mismatch, array element type " +
"or length mismatch, or a reference/container)",
_driverInstanceId, reference, def.DataType, symbolName);
else
_logger.LogWarning(
@@ -531,7 +532,7 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery
// client swap unchanged — replay re-registers the SAME intent onto the new client.
var reg = new NativeRegistration(
Interlocked.Increment(ref _nextRegId), device, reference, symbolName,
def.DataType, bitIndex, publishingInterval,
def.DataType, bitIndex, def.ArrayLength, publishingInterval,
onChange: (_, value) => OnDataChange?.Invoke(this,
new DataChangeEventArgs(handle, reference, new DataValueSnapshot(
value, TwinCATStatusMapper.Good, DateTime.UtcNow, DateTime.UtcNow))),
@@ -545,17 +546,19 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery
{
await RegisterNotificationAsync(device, reg, cancellationToken).ConfigureAwait(false);
}
catch (TwinCATTypeMismatchException mismatch)
catch (TwinCATNotificationRefusedException refused)
{
// The declared type cannot decode this PLC symbol (ignitionoee TwinCAT-002/-008):
// isolate THIS tag to Bad — one WARN, one BadTypeMismatch snapshot — and keep the
// rest of the subscription. Its intent stays on the device with no live handle,
// so the probe-tick retry re-checks it after a PLC program change.
// The declared type / array length cannot decode this PLC symbol (ignitionoee
// TwinCAT-002/-008), or the array is over the native-notification size cap: isolate
// THIS tag to Bad — one WARN, one snapshot carrying the refusal's status
// (BadTypeMismatch / BadOutOfRange) — and keep the rest of the subscription. Its
// intent stays on the device with no live handle, so the probe-tick retry re-checks
// it after a PLC program change.
_logger.LogWarning(
"TwinCAT driver '{DriverInstanceId}' refused native notification for '{Reference}': {Reason}",
_driverInstanceId, reference, mismatch.Message);
_driverInstanceId, reference, refused.Message);
OnDataChange?.Invoke(this, new DataChangeEventArgs(handle, reference, new DataValueSnapshot(
null, TwinCATStatusMapper.BadTypeMismatch, null, DateTime.UtcNow)));
null, refused.StatusCode, null, DateTime.UtcNow)));
}
registrations.Add(reg);
}
@@ -594,10 +597,10 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery
try
{
newHandle = await client.AddNotificationAsync(
reg.SymbolName, reg.DataType, reg.BitIndex, reg.Interval,
reg.SymbolName, reg.DataType, reg.BitIndex, reg.ArrayLength, reg.Interval,
_options.NotificationMaxDelayMs, reg.OnChange, ct).ConfigureAwait(false);
}
catch (TwinCATTypeMismatchException)
catch (TwinCATNotificationRefusedException)
{
// Keep the intent with no live handle (a "dead" registration) so the probe-tick
// retry re-checks it and UnsubscribeAsync still removes it; the caller isolates it.
@@ -659,6 +662,8 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery
public TwinCATDataType DataType { get; }
/// <summary>Bit index for a BOOL-within-word symbol; null otherwise.</summary>
public int? BitIndex { get; }
/// <summary>Authored array length — the whole array is registered and published; null for a scalar.</summary>
public int? ArrayLength { get; }
/// <summary>Requested notification interval.</summary>
public TimeSpan Interval { get; }
/// <summary>Value-change callback (closes over the owning subscription handle + reference).</summary>
@@ -687,11 +692,12 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery
/// <param name="symbolName">ADS symbol name (resolved from the symbol path).</param>
/// <param name="dataType">Declared data type.</param>
/// <param name="bitIndex">Bit index for a BOOL-within-word symbol; null otherwise.</param>
/// <param name="arrayLength">Authored array length for an array tag; null for a scalar.</param>
/// <param name="interval">Requested notification interval.</param>
/// <param name="onChange">Value-change callback (closes over the owning subscription handle + reference).</param>
/// <param name="onUnavailable">Bad-quality callback fired when the handle goes dead (05/STAB-16).</param>
public NativeRegistration(long id, DeviceState device, string reference, string symbolName,
TwinCATDataType dataType, int? bitIndex, TimeSpan interval, Action<string, object?> onChange,
TwinCATDataType dataType, int? bitIndex, int? arrayLength, TimeSpan interval, Action<string, object?> onChange,
Action onUnavailable)
{
Id = id;
@@ -700,6 +706,7 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery
SymbolName = symbolName;
DataType = dataType;
BitIndex = bitIndex;
ArrayLength = arrayLength;
Interval = interval;
OnChange = onChange;
OnUnavailable = onUnavailable;
@@ -969,7 +976,7 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery
try
{
var newHandle = await client.AddNotificationAsync(
reg.SymbolName, reg.DataType, reg.BitIndex, reg.Interval,
reg.SymbolName, reg.DataType, reg.BitIndex, reg.ArrayLength, reg.Interval,
_options.NotificationMaxDelayMs, reg.OnChange, ct).ConfigureAwait(false);
var old = reg.SwapHandle(newHandle);
try { old?.Dispose(); } catch { /* dead handle from the disposed client */ }
@@ -1034,7 +1041,7 @@ public sealed class TwinCATDriver : IDriver, IReadable, IWritable, ITagDiscovery
try
{
var newHandle = await client.AddNotificationAsync(
reg.SymbolName, reg.DataType, reg.BitIndex, reg.Interval,
reg.SymbolName, reg.DataType, reg.BitIndex, reg.ArrayLength, reg.Interval,
_options.NotificationMaxDelayMs, reg.OnChange, ct).ConfigureAwait(false);
reg.SwapHandle(newHandle);
// STAB-17 ownership re-check — see ReplayNativeRegistrationsAsync.
@@ -0,0 +1,28 @@
namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT;
/// <summary>
/// Thrown by <see cref="ITwinCATClient.AddNotificationAsync"/> when the client refuses to register a
/// native notification for one tag — its declared type cannot decode the PLC symbol
/// (<see cref="TwinCATTypeMismatchException"/>), or an array is too large for a native notification.
/// The driver isolates that one tag to <see cref="StatusCode"/> (one WARN) and keeps the rest of the
/// subscription; the intent stays registered so the probe-tick retry re-checks it.
/// </summary>
internal class TwinCATNotificationRefusedException : Exception
{
/// <summary>Initializes a new instance of the <see cref="TwinCATNotificationRefusedException"/> class.</summary>
/// <param name="symbolPath">The ADS symbol the tag names.</param>
/// <param name="reason">The one-line reason.</param>
/// <param name="statusCode">The OPC UA status the refused tag publishes.</param>
public TwinCATNotificationRefusedException(string symbolPath, string reason, uint statusCode)
: base($"TwinCAT symbol '{symbolPath}': {reason}")
{
SymbolPath = symbolPath;
StatusCode = statusCode;
}
/// <summary>Gets the ADS symbol the refused tag names.</summary>
public string SymbolPath { get; }
/// <summary>Gets the OPC UA status the refused tag publishes.</summary>
public uint StatusCode { get; }
}
@@ -78,6 +78,31 @@ internal readonly record struct TwinCATPlcSymbolShape(TwinCATPlcKind Kind, int B
}
}
/// <summary>The facts about a PLC ARRAY symbol <see cref="TwinCATTypeGuard.CheckArray"/> plans a layout from.</summary>
/// <param name="DimensionLengths">The element count of each dimension (lower bounds play no part: the
/// driver publishes a 0-based, flattened array in PLC memory order).</param>
/// <param name="ByteSize">The array's byte size, from its RESOLVED data type (a TwinCAT 2 member symbol
/// under-reports its own size).</param>
/// <param name="Element">The (alias-resolved) element type, classified like a scalar symbol.</param>
internal readonly record struct TwinCATPlcArrayShape(IReadOnlyList<int> DimensionLengths, int ByteSize, TwinCATPlcSymbolShape Element)
{
/// <summary>Gets the total element count across every dimension (0 when any dimension is empty).</summary>
public long ElementCount => DimensionLengths.Aggregate(1L, (total, length) => total * Math.Max(0, length));
}
/// <summary>
/// How an array tag is read from the PLC's raw bytes: <paramref name="ElementCount"/> elements at a
/// fixed <paramref name="Stride"/>, starting at the array's first byte.
/// </summary>
/// <param name="ElementCount">The number of elements published (the authored <c>ArrayLength</c>).</param>
/// <param name="Stride">The bytes per element: the element type's width, or n+1 / 2(n+1) for a
/// <c>STRING(n)</c> / <c>WSTRING(n)</c>.</param>
internal readonly record struct TwinCATArrayLayout(int ElementCount, int Stride)
{
/// <summary>Gets the number of bytes the read or notification covers.</summary>
public int ByteLength => ElementCount * Stride;
}
/// <summary>
/// Decides whether a tag's DECLARED <see cref="TwinCATDataType"/> may decode the PLC symbol it names —
/// the port of the ignitionoee TwinCAT driver's extra-type reconciliation (TwinCAT-002, -008). A
@@ -132,7 +157,10 @@ internal static class TwinCATTypeGuard
if (reason is not null || StringKindOf(declared) is not null) return reason;
if (plc.Kind == TwinCATPlcKind.NonScalar)
return $"declared scalar {declared} but the PLC symbol is {plc.TypeName} ({plc.ByteSize} B) — not a scalar";
return $"declared scalar {declared} but the PLC symbol is {plc.TypeName} ({plc.ByteSize} B) — not a scalar" +
(plc.TypeName.StartsWith("ARRAY", StringComparison.OrdinalIgnoreCase)
? " (author it as an array tag: isArray + arrayLength)"
: string.Empty);
var size = DeclaredByteSize(declared);
if (size != plc.ByteSize)
@@ -144,6 +172,72 @@ internal static class TwinCATTypeGuard
: $"declared {declared} but the PLC symbol is {plc.TypeName} — float/integer kinds differ";
}
/// <summary>
/// The largest array a native notification registers, in bytes: 128 KiB — the largest registration
/// proven on a real target (a TwinCAT 2.11 <c>ARRAY [0..65535] OF UINT</c>, live 2026-10-07; ADS
/// itself documents no notification size limit). The PLC compares the whole buffer every cycle for
/// an on-change notification, and every change is copied through the router and the driver's
/// notification queue, so a bigger array is refused rather than registered blind.
/// </summary>
public const int MaxNotificationArrayBytes = 128 * 1024;
/// <summary>
/// Checks an ARRAY tag — its declared element type and authored <c>ArrayLength</c> — against a PLC
/// array, and plans the raw-bytes layout both the poll read and the native notification decode
/// with <see cref="TwinCATArrayCodec"/>.
/// </summary>
/// <remarks>
/// <list type="bullet">
/// <item>The element is checked like a scalar notification (<see cref="CheckNotification"/>):
/// the bytes are decoded as the DECLARED element type, so width, float/integer and string kind
/// must agree. Struct / FB / pointer / nested-array (jagged) elements are refused.</item>
/// <item>A multi-dimensional array is published flattened in PLC memory order (the last index
/// varies fastest); its <c>ArrayLength</c> is the total element count. Lower bounds play no
/// part — the published index is 0-based.</item>
/// <item>An authored <c>ArrayLength</c> SHORTER than the PLC array reads the leading sub-range
/// (the first N elements, N × stride bytes from the array start); a LONGER one is refused, since
/// it would read past the array.</item>
/// </list>
/// </remarks>
/// <param name="declared">The tag's declared element type.</param>
/// <param name="declaredLength">The tag's authored <c>ArrayLength</c>.</param>
/// <param name="symbol">The PLC symbol's shape (decides a non-array symbol; names it in messages).</param>
/// <param name="array">The PLC array's shape, or null when the symbol is not an array.</param>
/// <param name="layout">The planned layout when compatible; otherwise default.</param>
/// <returns><c>null</c> when compatible; otherwise the reason.</returns>
public static string? CheckArray(TwinCATDataType declared, int declaredLength, TwinCATPlcSymbolShape symbol,
TwinCATPlcArrayShape? array, out TwinCATArrayLayout layout)
{
layout = default;
if (declaredLength <= 0)
return $"declared an array of {declaredLength} {declared} elements — an array tag needs arrayLength >= 1";
if (array is not { } plc || symbol.TypeName.Contains("VAR_IN_OUT", StringComparison.OrdinalIgnoreCase))
return $"declared an array of {declaredLength} {declared} but the PLC symbol is {symbol.TypeName} " +
$"({symbol.ByteSize} B) — not an array";
if (CheckNotification(declared, plc.Element) is { } elementReason)
return $"{symbol.TypeName}: element {elementReason}";
var stride = plc.Element.ByteSize;
var count = plc.ElementCount;
if (stride <= 0 || count <= 0 || count * stride != plc.ByteSize)
return $"{symbol.TypeName} is {plc.ByteSize} B, not {count} × {stride} B elements — not a packed array";
if (declaredLength > count)
return $"declared arrayLength {declaredLength} but the PLC array {symbol.TypeName} has {count} elements";
layout = new TwinCATArrayLayout(declaredLength, stride);
return null;
}
/// <summary>Checks a planned array layout against <see cref="MaxNotificationArrayBytes"/>.</summary>
/// <param name="layout">The planned layout.</param>
/// <returns><c>null</c> when it fits; otherwise the reason.</returns>
public static string? CheckNotificationSize(TwinCATArrayLayout layout) =>
layout.ByteLength <= MaxNotificationArrayBytes
? null
: $"{layout.ElementCount} elements ({layout.ByteLength} B) exceed the {MaxNotificationArrayBytes} B " +
"native-notification cap — author a shorter arrayLength or subscribe with UseNativeNotifications=false";
/// <summary>The byte width the declared type decodes from a notification buffer.</summary>
/// <param name="type">The declared type.</param>
/// <returns>The width in bytes.</returns>
@@ -2,21 +2,17 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT;
/// <summary>
/// Thrown by <see cref="ITwinCATClient.AddNotificationAsync"/> when a tag's declared
/// <see cref="TwinCATDataType"/> cannot decode the PLC symbol it names (see
/// <see cref="TwinCATTypeGuard"/>). The driver isolates the one tag to
/// <see cref="TwinCATStatusMapper.BadTypeMismatch"/> and keeps the rest of the subscription.
/// <see cref="TwinCATDataType"/> (or, for an array tag, its element type / <c>ArrayLength</c>) cannot
/// decode the PLC symbol it names (see <see cref="TwinCATTypeGuard"/>). The driver isolates the one
/// tag to <see cref="TwinCATStatusMapper.BadTypeMismatch"/> and keeps the rest of the subscription.
/// </summary>
internal sealed class TwinCATTypeMismatchException : Exception
internal sealed class TwinCATTypeMismatchException : TwinCATNotificationRefusedException
{
/// <summary>Initializes a new instance of the <see cref="TwinCATTypeMismatchException"/> class.</summary>
/// <param name="symbolPath">The ADS symbol the tag names.</param>
/// <param name="reason">The guard's one-line reason.</param>
public TwinCATTypeMismatchException(string symbolPath, string reason)
: base($"TwinCAT symbol '{symbolPath}': {reason}")
: base(symbolPath, reason, TwinCATStatusMapper.BadTypeMismatch)
{
SymbolPath = symbolPath;
}
/// <summary>Gets the ADS symbol the refused tag names.</summary>
public string SymbolPath { get; }
}
@@ -129,13 +129,14 @@ internal class FakeTwinCATClient : ITwinCATClient
/// <param name="symbolPath">The path to the symbol to watch.</param>
/// <param name="type">The data type of the symbol.</param>
/// <param name="bitIndex">The optional bit index for bit-level notifications.</param>
/// <param name="arrayCount">The authored array length for an array tag; null for a scalar.</param>
/// <param name="cycleTime">The sampling cycle time.</param>
/// <param name="maxDelayMs">The maximum delay in milliseconds.</param>
/// <param name="onChange">The callback to invoke on value change.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>A task that returns a notification handle.</returns>
public virtual async Task<ITwinCATNotificationHandle> AddNotificationAsync(
string symbolPath, TwinCATDataType type, int? bitIndex, TimeSpan cycleTime,
string symbolPath, TwinCATDataType type, int? bitIndex, int? arrayCount, TimeSpan cycleTime,
int maxDelayMs, Action<string, object?> onChange, CancellationToken cancellationToken)
{
if (ThrowOnAddNotification)
@@ -147,7 +148,7 @@ internal class FakeTwinCATClient : ITwinCATClient
await gate.Task.ConfigureAwait(false);
LastMaxDelayMs = maxDelayMs;
var reg = new FakeNotification(symbolPath, type, bitIndex, onChange, this);
var reg = new FakeNotification(symbolPath, type, bitIndex, onChange, this) { ArrayCount = arrayCount };
Notifications.Add(reg);
return reg;
}
@@ -195,6 +196,8 @@ internal class FakeTwinCATClient : ITwinCATClient
public TwinCATDataType Type { get; } = type;
/// <summary>Gets the optional bit index.</summary>
public int? BitIndex { get; } = bitIndex;
/// <summary>Gets the array count the driver registered with (null = scalar).</summary>
public int? ArrayCount { get; init; }
/// <summary>Gets the callback to invoke on value change.</summary>
public Action<string, object?> OnChange { get; } = onChange;
/// <summary>Gets a value indicating whether this notification has been disposed.</summary>
@@ -0,0 +1,268 @@
using System.Buffers.Binary;
using System.Text;
using Shouldly;
using TwinCAT.TypeSystem;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Driver.TwinCAT;
namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT.Tests;
/// <summary>
/// Pins the array half of the raw-bytes model: <see cref="TwinCATTypeGuard.CheckArray"/> decides
/// whether an authored array tag (element type + <c>ArrayLength</c>) may decode a PLC array and
/// plans the byte layout, and <see cref="TwinCATArrayCodec.Decode"/> turns the PLC's raw bytes into
/// the element-typed CLR array both the poll read and the native notification publish.
/// </summary>
/// <remarks>
/// The raw-bytes model replaced the Beckhoff typed array read after the 2026-10-07 live gate on the
/// TwinCAT 2.11 Elma cleaner Z33856, where that read failed for most real arrays: the CLR element
/// type had to match exactly (<c>ARRAY OF TIME</c> as <c>uint[]</c> threw), a multi-dimensional
/// array demanded a rank-2 CLR array, and a dotted MEMBER array was sliced by the under-reported
/// symbol size (<c>P_INPUTVALUESFILTER.FBUSPWR1G1.SAMPLE</c>, <c>ARRAY [1..20] OF REAL</c>, symbol
/// 10 B vs type 80 B → <c>ArgumentOutOfRangeException</c>).
/// </remarks>
[Trait("Category", "Unit")]
public sealed class TwinCATArrayCodecTests
{
private static TwinCATPlcSymbolShape Elem(string typeName, int byteSize, DataTypeCategory? category = DataTypeCategory.Primitive)
=> TwinCATPlcSymbolShape.Classify(typeName, category, byteSize);
private static TwinCATPlcArrayShape Arr(TwinCATPlcSymbolShape element, params int[] dims)
=> new(dims, dims.Aggregate(1, (a, b) => a * b) * element.ByteSize, element);
private static TwinCATPlcSymbolShape ArraySymbol(string typeName, int byteSize)
=> TwinCATPlcSymbolShape.Classify(typeName, DataTypeCategory.Array, byteSize);
private static string? Check(TwinCATDataType declared, int declaredLength, TwinCATPlcArrayShape? array,
out TwinCATArrayLayout layout, string typeName = "ARRAY")
=> TwinCATTypeGuard.CheckArray(declared, declaredLength,
ArraySymbol(typeName, array?.ByteSize ?? 4), array, out layout);
// ---- guard: plan + validate ----
/// <summary>A matching element type and length plans the whole array at element-size stride.</summary>
[Fact]
public void CheckArray_plans_a_matching_numeric_array_at_its_element_stride()
{
Check(TwinCATDataType.UInt, 13, Arr(Elem("UINT", 2), 13), out var layout).ShouldBeNull();
layout.ShouldBe(new TwinCATArrayLayout(13, 2));
layout.ByteLength.ShouldBe(26);
}
/// <summary>
/// A multi-dimensional array (<c>ARRAY [1..3, 1..2] OF REAL</c>, live on Z33856) is published
/// flattened in PLC memory order; its ArrayLength is the TOTAL element count. Lower bounds play
/// no part — the published index is 0-based.
/// </summary>
[Fact]
public void CheckArray_flattens_a_multi_dimensional_array_to_its_total_count()
{
Check(TwinCATDataType.Real, 6, Arr(Elem("REAL", 4), 3, 2), out var layout).ShouldBeNull();
layout.ShouldBe(new TwinCATArrayLayout(6, 4));
}
/// <summary>
/// An authored ArrayLength SHORTER than the PLC array reads the leading sub-range only: the first
/// N elements in PLC memory order, at N × stride bytes from the array start — cheap (a smaller
/// notification) and well-defined, and it matches the node's advertised ArrayDimensions.
/// </summary>
[Fact]
public void CheckArray_plans_a_leading_sub_range_when_the_authored_length_is_shorter()
{
Check(TwinCATDataType.Real, 5, Arr(Elem("REAL", 4), 20), out var layout).ShouldBeNull();
layout.ShouldBe(new TwinCATArrayLayout(5, 4));
layout.ByteLength.ShouldBe(20);
}
/// <summary>An authored ArrayLength LONGER than the PLC array would read past it — refused.</summary>
[Fact]
public void CheckArray_refuses_an_authored_length_longer_than_the_plc_array()
=> Check(TwinCATDataType.UInt, 14, Arr(Elem("UINT", 2), 13), out _)!.ShouldContain("13");
/// <summary>A zero or negative authored length is not an array.</summary>
[Fact]
public void CheckArray_refuses_a_non_positive_authored_length()
=> Check(TwinCATDataType.UInt, 0, Arr(Elem("UINT", 2), 13), out _).ShouldNotBeNull();
/// <summary>
/// The element is checked with the same rules as a scalar notification (TwinCAT-002/-008): width,
/// float/integer kind and string kind must agree; a same-width, same-kind divergence is tolerated.
/// </summary>
[Fact]
public void CheckArray_checks_the_element_like_a_scalar_notification()
{
Check(TwinCATDataType.DInt, 4, Arr(Elem("REAL", 4), 4), out _).ShouldNotBeNull(); // float kind
Check(TwinCATDataType.Int, 4, Arr(Elem("DINT", 4), 4), out _).ShouldNotBeNull(); // width
Check(TwinCATDataType.DInt, 4, Arr(Elem("STRING(80)", 81, DataTypeCategory.String), 4), out _).ShouldNotBeNull();
Check(TwinCATDataType.String, 4, Arr(Elem("INT", 2), 4), out _).ShouldNotBeNull();
Check(TwinCATDataType.WString, 4, Arr(Elem("STRING(80)", 81, DataTypeCategory.String), 4), out _).ShouldNotBeNull();
Check(TwinCATDataType.Int, 4, Arr(Elem("UINT", 2), 4), out _).ShouldBeNull(); // same width, same kind
Check(TwinCATDataType.Time, 13, Arr(Elem("TIME", 4), 13), out _).ShouldBeNull();
Check(TwinCATDataType.USInt, 6, Arr(Elem("USINT", 1), 6), out _).ShouldBeNull();
Check(TwinCATDataType.SInt, 13, Arr(Elem("BYTE", 1), 13), out _).ShouldBeNull();
Check(TwinCATDataType.Bool, 19, Arr(Elem("BOOL", 1), 19), out _).ShouldBeNull();
Check(TwinCATDataType.LReal, 32, Arr(Elem("LREAL", 8), 32), out _).ShouldBeNull();
}
/// <summary>A STRING(n) / WSTRING(n) element is laid out at the PLC's own width: n+1 / 2(n+1).</summary>
[Fact]
public void CheckArray_strides_a_string_array_by_the_plc_element_width()
{
Check(TwinCATDataType.String, 10, Arr(Elem("STRING(80)", 81, DataTypeCategory.String), 10), out var s).ShouldBeNull();
s.ShouldBe(new TwinCATArrayLayout(10, 81));
Check(TwinCATDataType.WString, 3, Arr(Elem("WSTRING(20)", 42, DataTypeCategory.String), 3), out var w).ShouldBeNull();
w.ShouldBe(new TwinCATArrayLayout(3, 42));
}
/// <summary>
/// Arrays of structs / UDTs / FBs, of pointers, and arrays of arrays (jagged) have no scalar element
/// the driver can decode — refused with a reason that says so.
/// </summary>
[Fact]
public void CheckArray_refuses_struct_pointer_and_nested_array_elements()
{
Check(TwinCATDataType.DInt, 13, Arr(Elem("ST_CARRIERDATA", 120, DataTypeCategory.Struct), 13), out _).ShouldNotBeNull();
Check(TwinCATDataType.DInt, 4, Arr(Elem("POINTER TO BYTE", 4, DataTypeCategory.Pointer), 4), out _).ShouldNotBeNull();
Check(TwinCATDataType.Int, 2, Arr(Elem("ARRAY [0..2] OF INT", 6, DataTypeCategory.Array), 2), out _).ShouldNotBeNull();
}
/// <summary>
/// An array tag over a PLC symbol that is not an array (a scalar, a string, an element path such
/// as <c>Arr[3]</c>) is refused: there is no array to read.
/// </summary>
[Fact]
public void CheckArray_refuses_a_plc_symbol_that_is_not_an_array()
{
TwinCATTypeGuard.CheckArray(TwinCATDataType.DInt, 4, Elem("DINT", 4), null, out _).ShouldNotBeNull();
TwinCATTypeGuard.CheckArray(TwinCATDataType.String, 4,
Elem("STRING(80)", 81, DataTypeCategory.String), null, out _).ShouldNotBeNull();
}
/// <summary>A <c>VAR_IN_OUT</c> array member is a reference, not the array — refused.</summary>
[Fact]
public void CheckArray_refuses_a_var_in_out_reference()
{
var symbol = TwinCATPlcSymbolShape.Classify("ARRAY [1..3] OF INT", DataTypeCategory.Array, 4,
dataTypeByteSize: 6, symbolTypeName: "ARRAY [1..3] OF INT (VAR_IN_OUT)");
TwinCATTypeGuard.CheckArray(TwinCATDataType.Int, 3, symbol, Arr(Elem("INT", 2), 3), out _).ShouldNotBeNull();
}
/// <summary>
/// A layout whose element count × element size disagrees with the array's own byte size is not
/// a packed array the driver understands (padding, a mis-resolved element) — refused rather than
/// decoded at the wrong offsets.
/// </summary>
[Fact]
public void CheckArray_refuses_an_array_whose_size_is_not_count_times_element_size()
{
var padded = new TwinCATPlcArrayShape([4], 32, Elem("INT", 2));
Check(TwinCATDataType.Int, 4, padded, out _).ShouldNotBeNull();
}
// ---- guard: notification size ----
/// <summary>
/// A native notification is capped at <see cref="TwinCATTypeGuard.MaxNotificationArrayBytes"/>
/// (128 KiB — the largest registration proven on a real target: a TC 2.11
/// <c>ARRAY [0..65535] OF UINT</c>). Above it the tag is refused with a reason pointing at polling.
/// </summary>
[Fact]
public void CheckNotificationSize_caps_a_native_array_at_128_KiB()
{
TwinCATTypeGuard.MaxNotificationArrayBytes.ShouldBe(128 * 1024);
TwinCATTypeGuard.CheckNotificationSize(new TwinCATArrayLayout(65536, 2)).ShouldBeNull();
TwinCATTypeGuard.CheckNotificationSize(new TwinCATArrayLayout(65537, 2))!.ShouldContain("UseNativeNotifications");
}
// ---- codec: decode ----
/// <summary>Each numeric element type decodes little-endian into its CLR array, in PLC memory order.</summary>
[Fact]
public void Decode_numeric_elements_little_endian_into_the_declared_clr_array()
{
Decode<short>(TwinCATDataType.Int, 2, [-1, 300], (b, v) => BinaryPrimitives.WriteInt16LittleEndian(b, v));
Decode<ushort>(TwinCATDataType.UInt, 2, [65535, 7], (b, v) => BinaryPrimitives.WriteUInt16LittleEndian(b, v));
Decode<int>(TwinCATDataType.DInt, 4, [-123456, 42], (b, v) => BinaryPrimitives.WriteInt32LittleEndian(b, v));
Decode<uint>(TwinCATDataType.UDInt, 4, [4_000_000_000, 1], (b, v) => BinaryPrimitives.WriteUInt32LittleEndian(b, v));
Decode<long>(TwinCATDataType.LInt, 8, [long.MinValue, 9], (b, v) => BinaryPrimitives.WriteInt64LittleEndian(b, v));
Decode<ulong>(TwinCATDataType.ULInt, 8, [ulong.MaxValue, 3], (b, v) => BinaryPrimitives.WriteUInt64LittleEndian(b, v));
Decode<float>(TwinCATDataType.Real, 4, [949.2f, -0.5f], (b, v) => BinaryPrimitives.WriteSingleLittleEndian(b, v));
Decode<double>(TwinCATDataType.LReal, 8, [Math.PI, -1e300], (b, v) => BinaryPrimitives.WriteDoubleLittleEndian(b, v));
Decode<sbyte>(TwinCATDataType.SInt, 1, [-128, 127], (b, v) => b[0] = unchecked((byte)v));
Decode<byte>(TwinCATDataType.USInt, 1, [0, 255], (b, v) => b[0] = v);
}
/// <summary>
/// TIME / DATE / DT / TOD elements publish as their raw 32-bit count (<c>uint[]</c>) — the same
/// CLR shape a scalar of those types publishes. Live: <c>.THROTTLE_MODE_DEFAULT</c>
/// (<c>ARRAY [0..12] OF TIME</c>) begins <c>0, 10, 20</c> ms.
/// </summary>
[Theory]
[InlineData(TwinCATDataType.Time)]
[InlineData(TwinCATDataType.Date)]
[InlineData(TwinCATDataType.DateTime)]
[InlineData(TwinCATDataType.TimeOfDay)]
public void Decode_time_and_date_elements_as_uint(TwinCATDataType type)
=> TwinCATArrayCodec.Decode(type, [0, 0, 0, 0, 10, 0, 0, 0, 20, 0, 0, 0], new TwinCATArrayLayout(3, 4), utf8: false)
.ShouldBe(new uint[] { 0, 10, 20 });
/// <summary>A BOOL element is one byte; any non-zero byte is TRUE (live: <c>.ARGTYPE_IS_BIT_TYPE</c>).</summary>
[Fact]
public void Decode_bool_elements_one_byte_each_non_zero_is_true()
=> TwinCATArrayCodec.Decode(TwinCATDataType.Bool, [0, 1, 1, 0xFF, 0], new TwinCATArrayLayout(5, 1), utf8: false)
.ShouldBe(new[] { false, true, true, true, false });
/// <summary>
/// Each STRING(n) element sits at a fixed n+1 stride and ends at ITS first NUL — the stale tail a
/// longer earlier value left (live on Z33856) never leaks into the element, nor into the next one.
/// Windows-1252 unless the target reports UTF-8, exactly like a scalar string.
/// </summary>
[Fact]
public void Decode_string_elements_at_their_stride_each_ending_at_its_first_nul()
{
var bytes = new byte[3 * 6]; // STRING(5)
"RUN"u8.CopyTo(bytes.AsSpan(0));
bytes[4] = (byte)'T'; // stale tail after the NUL
"MON_O"u8.CopyTo(bytes.AsSpan(6)); // full-length, no NUL before the stride end
bytes[12] = 0xB0; // '°' in Windows-1252
TwinCATArrayCodec.Decode(TwinCATDataType.String, bytes, new TwinCATArrayLayout(3, 6), utf8: false)
.ShouldBe(new[] { "RUN", "MON_O", "°" });
var utf8 = new byte[2 * 4];
"°C"u8.CopyTo(utf8.AsSpan(0));
TwinCATArrayCodec.Decode(TwinCATDataType.String, utf8, new TwinCATArrayLayout(2, 4), utf8: true)
.ShouldBe(new[] { "°C", "" });
}
/// <summary>Each WSTRING(n) element is UTF-16LE at a 2(n+1) stride, ending at its first aligned U+0000.</summary>
[Fact]
public void Decode_wstring_elements_at_their_stride()
{
var bytes = new byte[2 * 8]; // WSTRING(3)
Encoding.Unicode.GetBytes("Ab").CopyTo(bytes, 0);
Encoding.Unicode.GetBytes("Zürn").CopyTo(bytes, 8); // 4 chars fill the whole stride
TwinCATArrayCodec.Decode(TwinCATDataType.WString, bytes, new TwinCATArrayLayout(2, 8), utf8: false)
.ShouldBe(new[] { "Ab", "Zürn" });
}
/// <summary>A sub-range layout decodes only its leading elements, even from a longer buffer.</summary>
[Fact]
public void Decode_honours_the_layout_count_not_the_buffer_length()
=> TwinCATArrayCodec.Decode(TwinCATDataType.Int, [1, 0, 2, 0, 3, 0], new TwinCATArrayLayout(2, 2), utf8: false)
.ShouldBe(new short[] { 1, 2 });
/// <summary>A buffer shorter than the layout is a protocol fault, never a silently-short array.</summary>
[Fact]
public void Decode_refuses_a_buffer_shorter_than_the_layout()
=> Should.Throw<ArgumentException>(() =>
TwinCATArrayCodec.Decode(TwinCATDataType.Int, [1, 0, 2], new TwinCATArrayLayout(2, 2), utf8: false));
private static void Decode<T>(TwinCATDataType type, int stride, T[] values, Action<Span<byte>, T> write)
{
var bytes = new byte[values.Length * stride];
for (var i = 0; i < values.Length; i++) write(bytes.AsSpan(i * stride, stride), values[i]);
var decoded = TwinCATArrayCodec.Decode(type, bytes, new TwinCATArrayLayout(values.Length, stride), utf8: false);
decoded.ShouldBeOfType<T[]>().ShouldBe(values);
}
}
@@ -0,0 +1,137 @@
using System.Collections.Concurrent;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
using ZB.MOM.WW.OtOpcUa.Driver.TwinCAT;
namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT.Tests;
/// <summary>
/// Native ADS notifications for ARRAY tags. Before this, the notification path registered only the
/// declared scalar, so an array tag published its first element at Good; the declared-type guard
/// then refused every array tag with <c>BadTypeMismatch</c>. The driver now hands the authored
/// <c>ArrayLength</c> to the client, which registers the whole array as raw bytes and decodes it
/// (<see cref="TwinCATArrayCodec"/>) — these pin the driver's half of that contract.
/// </summary>
[Trait("Category", "Unit")]
public sealed class TwinCATNativeArraySubscribeTests
{
private const string Host = "ads://5.23.91.23.1.1:851";
private static (TwinCATDriver drv, FakeTwinCATClientFactory factory) NewNativeDriver(params TwinCATTagDefinition[] tags)
{
var factory = new FakeTwinCATClientFactory();
var drv = new TwinCATDriver(new TwinCATDriverOptions
{
Devices = [new TwinCATDeviceOptions(Host)],
RawTags = TwinCATRawTags.Entries(tags),
Probe = new TwinCATProbeOptions { Enabled = false },
UseNativeNotifications = true,
}, "drv-1", factory);
return (drv, factory);
}
/// <summary>
/// An array tag registers with its authored ArrayLength, and the element-typed array the client
/// decodes reaches OnDataChange whole, at Good — the same shape the poll read publishes.
/// </summary>
[Fact]
public async Task Native_subscribe_registers_an_array_tag_with_its_authored_length_and_publishes_the_array()
{
var (drv, factory) = NewNativeDriver(
new TwinCATTagDefinition("Samples", Host, "P_FILTER.SAMPLE", TwinCATDataType.Real, ArrayLength: 20));
await drv.InitializeAsync("{}", TestContext.Current.CancellationToken);
var events = new ConcurrentQueue<DataChangeEventArgs>();
drv.OnDataChange += (_, e) => events.Enqueue(e);
_ = await drv.SubscribeAsync(["Samples"], TimeSpan.FromMilliseconds(100), TestContext.Current.CancellationToken);
var reg = factory.Clients[0].Notifications.ShouldHaveSingleItem();
reg.Type.ShouldBe(TwinCATDataType.Real);
reg.ArrayCount.ShouldBe(20);
var samples = Enumerable.Range(1, 20).Select(i => i * 1.5f).ToArray();
factory.Clients[0].FireNotification("P_FILTER.SAMPLE", samples);
var e = events.ShouldHaveSingleItem();
e.Snapshot.StatusCode.ShouldBe(TwinCATStatusMapper.Good);
e.Snapshot.Value.ShouldBeSameAs(samples);
}
/// <summary>
/// A scalar tag, an element-indexed path (<c>Arr[3]</c>) and a bit-indexed BOOL stay scalars: no
/// array count reaches the client.
/// </summary>
[Fact]
public async Task Scalar_element_indexed_and_bit_indexed_tags_register_without_an_array_count()
{
var (drv, factory) = NewNativeDriver(
new TwinCATTagDefinition("Count", Host, "MAIN.Count", TwinCATDataType.DInt),
new TwinCATTagDefinition("Fault3", Host, "MAIN.FaultCodes[3]", TwinCATDataType.UInt),
new TwinCATTagDefinition("Run0", Host, "MAIN.State.0", TwinCATDataType.Bool));
await drv.InitializeAsync("{}", TestContext.Current.CancellationToken);
_ = await drv.SubscribeAsync(["Count", "Fault3", "Run0"], TimeSpan.FromMilliseconds(100), TestContext.Current.CancellationToken);
var regs = factory.Clients[0].Notifications;
regs.Count.ShouldBe(3);
regs.ShouldAllBe(n => n.ArrayCount == null);
regs.Single(n => n.SymbolPath == "MAIN.State.0").BitIndex.ShouldBe(0);
}
/// <summary>A reconnect replays an array registration with the same array count.</summary>
[Fact]
public async Task Reconnect_replays_an_array_registration_with_its_array_count()
{
var (drv, factory) = NewNativeDriver(
new TwinCATTagDefinition("Faults", Host, "MAIN.FaultCodes", TwinCATDataType.UInt, ArrayLength: 13));
await drv.InitializeAsync("{}", TestContext.Current.CancellationToken);
_ = await drv.SubscribeAsync(["Faults"], TimeSpan.FromMilliseconds(100), TestContext.Current.CancellationToken);
factory.Clients[0].SimulateWireDrop();
_ = await drv.ReadAsync(["Faults"], TestContext.Current.CancellationToken);
factory.Clients.Count.ShouldBe(2);
factory.Clients[1].Notifications.ShouldHaveSingleItem().ArrayCount.ShouldBe(13);
}
/// <summary>
/// A notification the client refuses for a reason other than a type mismatch (an array above the
/// native-notification size cap → <c>BadOutOfRange</c>) is isolated the same way: that one tag
/// publishes the refusal's own status and the rest of the subscription registers.
/// </summary>
[Fact]
public async Task A_refused_oversized_array_is_isolated_with_the_refusals_own_status()
{
var (drv, factory) = NewNativeDriver(
new TwinCATTagDefinition("Slaves", Host, "P_EC.SLAVEADDRESS", TwinCATDataType.UInt, ArrayLength: 70000),
new TwinCATTagDefinition("Count", Host, "MAIN.Count", TwinCATDataType.DInt));
factory.Customise = () =>
{
var c = new FakeTwinCATClient();
c.AddNotificationErrors["P_EC.SLAVEADDRESS"] = new TwinCATNotificationRefusedException(
"P_EC.SLAVEADDRESS", "140000 B exceeds the 131072 B native-notification cap",
TwinCATStatusMapper.BadOutOfRange);
return c;
};
await drv.InitializeAsync("{}", TestContext.Current.CancellationToken);
var events = new ConcurrentQueue<DataChangeEventArgs>();
drv.OnDataChange += (_, e) => events.Enqueue(e);
_ = await drv.SubscribeAsync(["Slaves", "Count"], TimeSpan.FromMilliseconds(100), TestContext.Current.CancellationToken);
factory.Clients[0].Notifications.ShouldHaveSingleItem().SymbolPath.ShouldBe("MAIN.Count");
var refused = events.ShouldHaveSingleItem();
refused.FullReference.ShouldBe("Slaves");
refused.Snapshot.StatusCode.ShouldBe(TwinCATStatusMapper.BadOutOfRange);
refused.Snapshot.Value.ShouldBeNull();
}
/// <summary>A type-mismatch refusal is a notification refusal carrying <c>BadTypeMismatch</c>.</summary>
[Fact]
public void A_type_mismatch_is_a_notification_refusal_carrying_BadTypeMismatch()
{
TwinCATNotificationRefusedException ex = new TwinCATTypeMismatchException("MAIN.X", "declared DInt over REAL");
ex.StatusCode.ShouldBe(TwinCATStatusMapper.BadTypeMismatch);
ex.SymbolPath.ShouldBe("MAIN.X");
}
}
@@ -191,13 +191,13 @@ public sealed class TwinCATNativeNotificationTests
/// <inheritdoc />
public override Task<ITwinCATNotificationHandle> AddNotificationAsync(
string symbolPath, TwinCATDataType type, int? bitIndex, TimeSpan cycleTime,
string symbolPath, TwinCATDataType type, int? bitIndex, int? arrayCount, TimeSpan cycleTime,
int maxDelayMs, Action<string, object?> onChange, CancellationToken cancellationToken)
{
AddCallCount++;
if (AddCallCount > _succeedBefore)
throw new InvalidOperationException($"fake fail on call #{AddCallCount}");
return base.AddNotificationAsync(symbolPath, type, bitIndex, cycleTime, maxDelayMs, onChange, cancellationToken);
return base.AddNotificationAsync(symbolPath, type, bitIndex, arrayCount, cycleTime, maxDelayMs, onChange, cancellationToken);
}
}