Hallucinate a whole ass prometheus exporter

.gitignore

@@ -1,2 +1,3 @@
 obj
 .vs/LibreHardwareMonitorExporter
+bin/Debug/net8.0

LibreHardwareMonitorExporter.csproj

@@ -7,4 +7,8 @@
     <Nullable>enable</Nullable>
   </PropertyGroup>
 
+  <ItemGroup>
+    <PackageReference Include="LibreHardwareMonitorLib" Version="0.9.4" />
+  </ItemGroup>
+
 </Project>

Program.cs

@@ -1,2 +1,143 @@
-// See https://aka.ms/new-console-template for more information
-Console.WriteLine("Hello, World!");
+using System.Net;
+using System.Text;
+using LibreHardwareMonitor.Hardware;
+
+var port = Environment.GetEnvironmentVariable("PORT");
+if (!int.TryParse(port, out var httpPort))
+{
+	httpPort = 9646; // default port
+}
+
+var listener = new HttpListener();
+listener.Prefixes.Add($"http://*:{httpPort}/");
+listener.Start();
+
+var computer = new Computer
+{
+	IsCpuEnabled = true,
+	IsGpuEnabled = true,
+	IsMemoryEnabled = true,
+	IsMotherboardEnabled = true,
+	IsControllerEnabled = true,
+	IsNetworkEnabled = true,
+	IsStorageEnabled = true
+};
+
+computer.Open();
+
+Console.WriteLine($"LibreHardwareMonitorExporter listening on http://localhost:{httpPort}/metrics");
+
+while (true)
+{
+	var context = await listener.GetContextAsync();
+	if (context.Request.HttpMethod != "GET")
+	{
+		context.Response.StatusCode = 405;
+		context.Response.Close();
+		continue;
+	}
+
+	if (context.Request.Url?.AbsolutePath != "/metrics")
+	{
+		context.Response.StatusCode = 404;
+		context.Response.Close();
+		continue;
+	}
+
+	var body = new StringBuilder();
+	AppendMetrics(body, computer);
+	var bytes = Encoding.UTF8.GetBytes(body.ToString());
+	context.Response.StatusCode = 200;
+	context.Response.ContentType = "text/plain; version=0.0.4";
+	context.Response.ContentEncoding = Encoding.UTF8;
+	context.Response.ContentLength64 = bytes.Length;
+	await context.Response.OutputStream.WriteAsync(bytes, 0, bytes.Length);
+	context.Response.Close();
+}
+
+static void AppendMetrics(StringBuilder output, Computer computer)
+{
+	var updateVisitor = new UpdateVisitor();
+	computer.Accept(updateVisitor);
+
+	// Basic example metrics for temperature, load, clock, power, fan
+	foreach (var hardware in computer.Hardware)
+	{
+		EmitHardwareMetrics(output, hardware);
+		foreach (var sub in hardware.SubHardware)
+		{
+			EmitHardwareMetrics(output, sub);
+		}
+	}
+}
+
+static void EmitHardwareMetrics(StringBuilder output, IHardware hardware)
+{
+	var hardwareLabel = SanitizeLabel(hardware.Name);
+	foreach (var sensor in hardware.Sensors)
+	{
+		if (sensor.Value is null) continue;
+		var sensorLabel = SanitizeLabel(sensor.Name);
+		var value = sensor.Value.Value;
+		var metricName = sensor.SensorType switch
+		{
+			SensorType.Temperature => "lhm_temperature_celsius",
+			SensorType.Load => "lhm_load_percent",
+			SensorType.Clock => "lhm_clock_mhz",
+			SensorType.Power => "lhm_power_watts",
+			SensorType.Fan => "lhm_fan_rpm",
+			SensorType.Voltage => "lhm_voltage_volts",
+			SensorType.Data => "lhm_data",
+			SensorType.Level => "lhm_level",
+			SensorType.Throughput => "lhm_throughput_bytes_per_sec",
+			SensorType.Factor => "lhm_factor",
+			SensorType.Flow => "lhm_flow_lph",
+			SensorType.Control => "lhm_control_percent",
+			_ => null
+		};
+
+		if (metricName == null) continue;
+		output.Append(metricName);
+		output.Append("{");
+		output.Append($"hardware=\"{hardwareLabel}\",sensor=\"{sensorLabel}\",type=\"{sensor.SensorType}\"");
+		output.Append("} ");
+		output.AppendLine(value.ToString(System.Globalization.CultureInfo.InvariantCulture));
+	}
+}
+
+static string SanitizeLabel(string raw)
+{
+	var sb = new StringBuilder(raw.Length);
+	foreach (var ch in raw)
+	{
+		if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') || (ch >= '0' && ch <= '9') || ch == '_' || ch == ':' || ch == '.')
+		{
+			sb.Append(ch);
+		}
+		else
+		{
+			sb.Append('_');
+		}
+	}
+	return sb.ToString();
+}
+
+sealed class UpdateVisitor : IVisitor
+{
+	public void VisitComputer(IComputer computer)
+	{
+		computer.Traverse(this);
+	}
+
+	public void VisitHardware(IHardware hardware)
+	{
+		hardware.Update();
+		foreach (var sub in hardware.SubHardware)
+		{
+			sub.Accept(this);
+		}
+	}
+
+	public void VisitSensor(ISensor sensor) { }
+	public void VisitParameter(IParameter parameter) { }
+}