feat: ship host metrics as a first-party in-process plugin

plugins/host-metrics/backend/widgets/temperature-collector.ts

@@ -0,0 +1,127 @@
+import type { Client } from "ssh2";
+import {
+  execCommand,
+  toFixedNum,
+} from "../../../../src/backend/hosts/metrics-shared/common-utils.js";
+
+export interface TemperatureSensor {
+  label: string;
+  celsius: number;
+}
+
+export interface TemperatureMetrics {
+  source: "sysfs" | "sensors" | "none";
+  highestCelsius: number | null;
+  sensors: TemperatureSensor[];
+}
+
+function normalizeSensor(
+  label: string,
+  celsius: number,
+): TemperatureSensor | null {
+  const cleanLabel = label.trim().replace(/\s+/g, " ");
+  if (!cleanLabel || !Number.isFinite(celsius)) return null;
+  return {
+    label: cleanLabel,
+    celsius: toFixedNum(celsius, 1) ?? celsius,
+  };
+}
+
+function summarizeSensors(
+  source: TemperatureMetrics["source"],
+  sensors: TemperatureSensor[],
+): TemperatureMetrics {
+  const highest = sensors.reduce<number | null>(
+    (max, sensor) =>
+      max === null ? sensor.celsius : Math.max(max, sensor.celsius),
+    null,
+  );
+
+  return {
+    source: sensors.length > 0 ? source : "none",
+    highestCelsius:
+      highest === null ? null : (toFixedNum(highest, 1) ?? highest),
+    sensors,
+  };
+}
+
+export function parseSysfsThermalOutput(output: string): TemperatureSensor[] {
+  return output
+    .split("\n")
+    .map((line) => {
+      const [label, rawValue] = line.split("\t");
+      const value = Number(rawValue);
+      if (!label || !Number.isFinite(value)) return null;
+      const celsius = Math.abs(value) >= 1000 ? value / 1000 : value;
+      return normalizeSensor(label, celsius);
+    })
+    .filter((sensor): sensor is TemperatureSensor => sensor !== null);
+}
+
+export function parseSensorsOutput(output: string): TemperatureSensor[] {
+  const seen = new Set<string>();
+  const sensors: TemperatureSensor[] = [];
+  let device = "";
+
+  for (const line of output.split("\n")) {
+    const trimmed = line.trim();
+    if (trimmed && !line.startsWith(" ") && !trimmed.includes(":")) {
+      device = trimmed;
+      continue;
+    }
+    const match = line.match(/^\s*([^:]+):\s*([+-]?\d+(?:\.\d+)?)\s*°?C\b/i);
+    if (!match) continue;
+
+    const label = device ? `${device}: ${match[1]}` : match[1];
+    const sensor = normalizeSensor(label, Number(match[2]));
+    if (!sensor) continue;
+
+    const key = `${sensor.label.toLowerCase()}:${sensor.celsius}`;
+    if (seen.has(key)) continue;
+    seen.add(key);
+    sensors.push(sensor);
+  }
+
+  return sensors;
+}
+
+export async function collectTemperatureMetrics(
+  client: Client,
+): Promise<TemperatureMetrics> {
+  try {
+    const sysfs = await execCommand(
+      client,
+      [
+        "for zone in /sys/class/thermal/thermal_zone*; do",
+        '[ -r "$zone/temp" ] || continue;',
+        'label="$(cat "$zone/type" 2>/dev/null || basename "$zone")";',
+        'value="$(cat "$zone/temp" 2>/dev/null || true)";',
+        '[ -n "$value" ] && printf "%s\\t%s\\n" "$label" "$value";',
+        "done",
+      ].join(" "),
+      10000,
+    );
+    const sensors = parseSysfsThermalOutput(sysfs.stdout);
+    if (sensors.length > 0) {
+      return summarizeSensors("sysfs", sensors);
+    }
+  } catch {
+    // expected on systems without readable thermal zones
+  }
+
+  try {
+    const lmSensors = await execCommand(client, "sensors 2>/dev/null", 10000);
+    const sensors = parseSensorsOutput(lmSensors.stdout);
+    if (sensors.length > 0) {
+      return summarizeSensors("sensors", sensors);
+    }
+  } catch {
+    // expected when lm-sensors is not installed
+  }
+
+  return {
+    source: "none",
+    highestCelsius: null,
+    sensors: [],
+  };
+}