Unit for monitoring some value via running of external program

ExternalMonitoringUnit.cs

@@ -0,0 +1,75 @@
+using NLog;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Text;
+using System.Text.Json;
+using System.Threading;
+
+namespace Barsik
+{
+	class ExternalMonitoringUnit : BaseMonitoringUnit
+	{
+		public ExternalMonitoringUnit(JsonElement config, RegistersContainer registers) : base(config, registers)
+		{
+		}
+
+		public override void GenerateItemsConfig(string name, StringBuilder config)
+		{
+			config.Append(string.Format("Number {0}_{1} \"{0} {1}\"", name, unitName));
+			config.Append(" {channel=\"");
+			config.AppendFormat("modbus:data:{0}:{1}:", name, unitName);
+			config.AppendFormat("{1}:number", name, unitName);
+			config.Append("\"}\n");
+		}
+
+		public override void GenerateThingsConfig(StringBuilder config)
+		{
+			config.Append("\tBridge poller ");
+			config.Append(unitName);
+			config.AppendFormat("[start = {0}, length = 2, type = \"holding\", refresh = 500] {{\n", baseAddress);
+			config.Append("\t\tThing data ");
+			config.Append(unitName);
+			config.AppendFormat("[readStart = \"{0}\", readValueType = \"float32\"]\n", baseAddress);
+			config.Append("\t}\n");
+		}
+
+		public override void Run()
+		{
+			string program = config.GetProperty("Program").GetString();
+			string args = config.GetProperty("Arguments").GetString(); 
+			var logger = LogManager.GetCurrentClassLogger();
+			while (true)
+			{
+				ProcessStartInfo procStartInfo = new ProcessStartInfo(program);
+				procStartInfo.Arguments = args;
+				procStartInfo.RedirectStandardOutput = true;
+				procStartInfo.UseShellExecute = false;
+				procStartInfo.CreateNoWindow = true;
+				using (Process proc = new Process())
+				{
+					proc.StartInfo = procStartInfo;
+					proc.Start();
+					while (!proc.HasExited)
+					{
+						Thread.Sleep(100);
+					}
+					string result = proc.StandardOutput.ReadToEnd();
+					result = result.Trim();
+					float resultFloat;
+					if (float.TryParse(result, out resultFloat))
+					{
+						registers.SetFloat(baseAddress, resultFloat);
+					}
+					else
+					{
+						logger.Error("Non-float result from process " + program + " with args " + args);
+						logger.Error("Result:");
+						logger.Error(result);
+					}
+				}
+				Thread.Sleep(2000);
+			}
+		}
+	}
+}

MonitoringUnit.cs

@@ -35,7 +35,11 @@ namespace Barsik
 			{
 				return new MDStatMonitoringUnit(config, registers);
 			}
-			else
+            else if (type == "External")
+            {
+                return new ExternalMonitoringUnit(config, registers);
+            }
+            else
             {
                 Console.WriteLine("Unknown unit type " + type);
                 return null;

RegistersContainer.cs

@@ -30,5 +30,12 @@ namespace Barsik
                 }
             }
         }
+
+        public void SetFloat(int address, float value)
+		{
+            byte[] bytes = BitConverter.GetBytes(value);
+            registers[address + 1] = (int)bytes[0] + (((int)bytes[1]) << 8);
+            registers[address] = (int)bytes[2] + (((int)bytes[3]) << 8);
+        }
     }
 }

barsik.json.sample

@@ -13,6 +13,13 @@
 			"Name": "RAID",
 			"Type": "MDStat", 
 			"BaseAddress": 3
+		},
+		{
+			"Name": "Some_Tool",
+			"Type": "External",
+			"BaseAddress": 100,
+			"Program": "cat",
+			"Arguments": "/dev/random"
 		}
 	]
 }