chore(auto): task completed - unknown

2026-06-13 13:12:41 +07:00
parent e413cf9fca
commit 4097b23dc3
4 changed files with 214 additions and 0 deletions
@@ -0,0 +1,6 @@
+export {
+  incrementCounter,
+  setGauge,
+  startMetricsServer,
+  stopMetricsServer,
+} from "./metrics.js";
@@ -0,0 +1,115 @@
+import http from "node:http";
+import { createChildLogger } from "@bete/shared/logger";
+import { config } from "../../shared/config/config.js";
+
+const logger = createChildLogger("gateway-metrics");
+
+// ─── Metrics Store ───────────────────────────────────────────────────────
+
+interface Metric {
+  help: string;
+  type: "counter" | "gauge";
+  value: number;
+  labels?: Record<string, string>;
+}
+
+const metrics = new Map<string, Metric>();
+
+// ─── Helpers ─────────────────────────────────────────────────────────────
+
+function key(name: string, labels?: Record<string, string>): string {
+  if (!labels) return name;
+  const labelStr = Object.entries(labels)
+    .sort(([a], [b]) => a.localeCompare(b))
+    .map(([k, v]) => `${k}="${v}"`)
+    .join(",");
+  return `${name}{${labelStr}}`;
+}
+
+// ─── Public API ──────────────────────────────────────────────────────────
+
+export function incrementCounter(
+  name: string,
+  labels?: Record<string, string>,
+): void {
+  const k = key(`bete_${name}`, labels);
+  const existing = metrics.get(k);
+  if (existing) {
+    existing.value += 1;
+  } else {
+    metrics.set(k, {
+      help: `Counter: ${name}`,
+      type: "counter",
+      value: 1,
+      labels: labels ? { ...labels } : undefined,
+    });
+  }
+}
+
+export function setGauge(
+  name: string,
+  value: number,
+  labels?: Record<string, string>,
+): void {
+  const k = key(`bete_${name}`, labels);
+  const existing = metrics.get(k);
+  if (existing) {
+    existing.value = value;
+  } else {
+    metrics.set(k, {
+      help: `Gauge: ${name}`,
+      type: "gauge",
+      value,
+      labels: labels ? { ...labels } : undefined,
+    });
+  }
+}
+
+// ─── HTTP Server ─────────────────────────────────────────────────────────
+
+let server: http.Server | null = null;
+
+function formatMetrics(): string {
+  const lines: string[] = [];
+
+  for (const [fullName, metric] of metrics) {
+    const baseName = fullName.includes("{") ? fullName.slice(0, fullName.indexOf("{")) : fullName;
+    lines.push(`# HELP ${baseName} ${metric.help}`);
+    lines.push(`# TYPE ${baseName} ${metric.type}`);
+    lines.push(`${fullName} ${metric.value}`);
+  }
+
+  return lines.join("\n") + "\n";
+}
+
+export function startMetricsServer(): void {
+  if (server) return;
+
+  const port = config.METRICS_PORT;
+  logger.info({ port }, "Starting metrics HTTP server");
+
+  server = http.createServer((req, res) => {
+    if (req.url === "/metrics" || req.url === "/health") {
+      res.writeHead(200, { "Content-Type": "text/plain; charset=utf-8" });
+      res.end(formatMetrics());
+    } else {
+      res.writeHead(404);
+      res.end("Not found");
+    }
+  });
+
+  server.listen(port, () => {
+    logger.info({ port }, "Metrics server listening");
+  });
+
+  server.on("error", (err) => {
+    logger.error({ error: err.message }, "Metrics server error");
+  });
+}
+
+export function stopMetricsServer(): void {
+  if (!server) return;
+  server.close();
+  server = null;
+  logger.info("Metrics server stopped");
+}