/// <summary>
/// Method to send a Modbus read request to a Modbus slave and returns the requested value(s)
/// providing common communication setup and associated exception handling (logging).
/// A TCP client is created and used to send the request to the Modbus TCP client.
/// The following requests are supported:
///
/// Single Coil
/// Single Discrete Input
/// Single Holding Register
/// Single Input Register
///
/// Multiple Coils
/// Multiple Discrete Inputs
/// Multiple Holding Registers
/// Multiple Input Registers
///
/// Additional datatypes (single values, value arrays and strings) with read
/// only access (discrete inputs and input registers) and read / write access
/// (coils and holding registers) are supported:
///
/// ASCII String (multiple registers)
/// Hex String (multiple registers)
/// Bool (single coil)
/// Bits (single register)
/// Short (single register)
/// UShort (single register)
/// Int32 (two registers)
/// UInt32 (two registers)
/// Float (two registers)
/// Double (four registers)
/// Long (four registers)
/// ULong (four registers)
///
/// </summary>
/// <param name="request">The <see cref="ModbusRequestData"/> data.</param>
/// <param name="function">The function name.</param>
/// <returns>A task returning an action method result.</returns>
protected async Task <IActionResult> ModbusReadRequest(ModbusRequestData request, string function)
{
try
{
request.Master = _client.RtuMaster;
if (_client.Connect())
{
switch (function)
{
case "ReadCoilAsync":
{
bool[] values = await _client.ReadCoilsAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseData <bool>(request, values[0])));
}
case "ReadCoilsAsync":
{
bool[] values = await _client.ReadCoilsAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <bool>(request, values)));
}
case "ReadInputAsync":
{
bool[] values = await _client.ReadInputsAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseData <bool>(request, values[0])));
}
case "ReadInputsAsync":
{
bool[] values = await _client.ReadInputsAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <bool>(request, values)));
}
case "ReadHoldingRegisterAsync":
{
ushort[] values = await _client.ReadHoldingRegistersAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseData <ushort>(request, values[0])));
}
case "ReadHoldingRegistersAsync":
{
ushort[] values = await _client.ReadHoldingRegistersAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <ushort>(request, values)));
}
case "ReadInputRegisterAsync":
{
ushort[] values = await _client.ReadInputRegistersAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseData <ushort>(request, values[0])));
}
case "ReadInputRegistersAsync":
{
ushort[] values = await _client.ReadInputRegistersAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <ushort>(request, values)));
}
case "ReadOnlyStringAsync":
{
string value = await _client.ReadOnlyStringAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseStringData(request, value)));
}
case "ReadOnlyHexStringAsync":
{
string value = await _client.ReadOnlyHexStringAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseStringData(request, value)));
}
case "ReadOnlyBoolAsync":
{
bool value = await _client.ReadOnlyBoolAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <bool>(request, value)));
}
case "ReadOnlyBitsAsync":
{
BitArray value = await _client.ReadOnlyBitsAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseStringData(request, value.ToDigitString())));
}
case "ReadOnlyShortAsync":
{
short value = await _client.ReadOnlyShortAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <short>(request, value)));
}
case "ReadOnlyUShortAsync":
{
ushort value = await _client.ReadOnlyUShortAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <ushort>(request, value)));
}
case "ReadOnlyInt32Async":
{
int value = await _client.ReadOnlyInt32Async(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <int>(request, value)));
}
case "ReadOnlyUInt32Async":
{
uint value = await _client.ReadOnlyUInt32Async(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <uint>(request, value)));
}
case "ReadOnlyFloatAsync":
{
float value = await _client.ReadOnlyFloatAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <float>(request, value)));
}
case "ReadOnlyDoubleAsync":
{
double value = await _client.ReadOnlyDoubleAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <double>(request, value)));
}
case "ReadOnlyLongAsync":
{
long value = await _client.ReadOnlyLongAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <long>(request, value)));
}
case "ReadOnlyULongAsync":
{
ulong value = await _client.ReadOnlyULongAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <ulong>(request, value)));
}
case "ReadOnlyBoolArrayAsync":
{
bool[] values = await _client.ReadOnlyBoolArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <bool>(request, values)));
}
case "ReadOnlyBytesAsync":
{
byte[] values = await _client.ReadOnlyBytesAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <byte>(request, values)));
}
case "ReadOnlyShortArrayAsync":
{
short[] values = await _client.ReadOnlyShortArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <short>(request, values)));
}
case "ReadOnlyUShortArrayAsync":
{
ushort[] values = await _client.ReadOnlyUShortArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <ushort>(request, values)));
}
case "ReadOnlyInt32ArrayAsync":
{
int[] values = await _client.ReadOnlyInt32ArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <int>(request, values)));
}
case "ReadOnlyUInt32ArrayAsync":
{
uint[] values = await _client.ReadOnlyUInt32ArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <uint>(request, values)));
}
case "ReadOnlyFloatArrayAsync":
{
float[] values = await _client.ReadOnlyFloatArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <float>(request, values)));
}
case "ReadOnlyDoubleArrayAsync":
{
double[] values = await _client.ReadOnlyDoubleArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <double>(request, values)));
}
case "ReadOnlyLongArrayAsync":
{
long[] values = await _client.ReadOnlyLongArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <long>(request, values)));
}
case "ReadOnlyULongArrayAsync":
{
ulong[] values = await _client.ReadOnlyULongArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <ulong>(request, values)));
}
case "ReadStringAsync":
{
string value = await _client.ReadStringAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseStringData(request, value)));
}
case "ReadHexStringAsync":
{
string value = await _client.ReadHexStringAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseStringData(request, value)));
}
case "ReadBoolAsync":
{
bool value = await _client.ReadBoolAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <bool>(request, value)));
}
case "ReadBitsAsync":
{
BitArray value = await _client.ReadBitsAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseStringData(request, value.ToDigitString())));
}
case "ReadShortAsync":
{
short value = await _client.ReadShortAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <short>(request, value)));
}
case "ReadUShortAsync":
{
ushort value = await _client.ReadUShortAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <ushort>(request, value)));
}
case "ReadInt32Async":
{
int value = await _client.ReadInt32Async(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <int>(request, value)));
}
case "ReadUInt32Async":
{
uint value = await _client.ReadUInt32Async(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <uint>(request, value)));
}
case "ReadFloatAsync":
{
float value = await _client.ReadFloatAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <float>(request, value)));
}
case "ReadDoubleAsync":
{
double value = await _client.ReadDoubleAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <double>(request, value)));
}
case "ReadLongAsync":
{
long value = await _client.ReadLongAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <long>(request, value)));
}
case "ReadULongAsync":
{
ulong value = await _client.ReadULongAsync(request.Slave.ID, request.Offset);
_logger.LogTrace($"{function}(): {value}");
return(Ok(new ModbusResponseData <ulong>(request, value)));
}
case "ReadBoolArrayAsync":
{
bool[] values = await _client.ReadBoolArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <bool>(request, values)));
}
case "ReadBytesAsync":
{
byte[] values = await _client.ReadBytesAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <byte>(request, values)));
}
case "ReadShortArrayAsync":
{
short[] values = await _client.ReadShortArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <short>(request, values)));
}
case "ReadUShortArrayAsync":
{
ushort[] values = await _client.ReadUShortArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <ushort>(request, values)));
}
case "ReadInt32ArrayAsync":
{
int[] values = await _client.ReadInt32ArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <int>(request, values)));
}
case "ReadUInt32ArrayAsync":
{
uint[] values = await _client.ReadUInt32ArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <uint>(request, values)));
}
case "ReadFloatArrayAsync":
{
float[] values = await _client.ReadFloatArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <float>(request, values)));
}
case "ReadDoubleArrayAsync":
{
double[] values = await _client.ReadDoubleArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <double>(request, values)));
}
case "ReadLongArrayAsync":
{
long[] values = await _client.ReadLongArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <long>(request, values)));
}
case "ReadULongArrayAsync":
{
ulong[] values = await _client.ReadULongArrayAsync(request.Slave.ID, request.Offset, request.Number);
_logger.LogTrace($"{function}(): {values}");
return(Ok(new ModbusResponseArrayData <ulong>(request, values)));
}
default:
_client.Disconnect();
_logger.LogError($"RTU master read request {function}() not supported.");
return(NotFound($"RTU master read request {function}() not supported."));
}
}
else
{
_logger.LogError($"RTU master ({request.Master.SerialPort}) not open.");
return(NotFound("RTU master COM port not open."));
}
}
catch (UnauthorizedAccessException uae)
{
_logger.LogError(uae, $"{function}() Unauthorized Access Exception.");
return(NotFound($"Unauthorized Access Exception: {uae.Message}"));
}
catch (ArgumentOutOfRangeException are)
{
_logger.LogError(are, $"{function}() Argument out of Range Exception.");
return(BadRequest($"Argument out of Range Exception: {are.Message}"));
}
catch (ArgumentException aex)
{
_logger.LogError(aex, $"{function}() Argument Exception.");
return(BadRequest($"Argument Exception: {aex.Message}"));
}
catch (NModbus.SlaveException mse)
{
_logger.LogError(mse, $"{function}() Modbus SlaveException.");
return(StatusCode(502, $"Modbus SlaveException: {mse.Message}"));
}
catch (System.IO.IOException ioe)
{
_logger.LogError(ioe, $"{function}() IO Exception.");
return(StatusCode(500, $"IO Exception: {ioe.Message}"));
}
catch (TimeoutException tex)
{
_logger.LogError(tex, $"{function}() Timeout Exception.");
return(StatusCode(500, $"Timeout Exception: {tex.Message}"));
}
catch (Exception ex)
{
_logger.LogError(ex, $"{function}() Exception.");
return(StatusCode(500, $"Exception: {ex.Message}"));
}
finally
{
if (_client.Connected)
{
_client.Disconnect();
}
}
}