From 0dd762e3a8e7c1d0d99056f691e3ed543db816ce Mon Sep 17 00:00:00 2001
From: evan <openfrontio@gmail.com>
Date: Fri, 2 May 2025 08:45:37 -0700
Subject: [PATCH] change worker metrics to guage

---
 src/server/Worker.ts        |   7 +-
 src/server/WorkerMetrics.ts | 129 +++++++++++++++++-------------------
 2 files changed, 61 insertions(+), 75 deletions(-)

diff --git a/src/server/Worker.ts b/src/server/Worker.ts
index cc4f970ea..9f87fa923 100644
--- a/src/server/Worker.ts
+++ b/src/server/Worker.ts
@@ -13,7 +13,7 @@ import { Client } from "./Client";
 import { GameManager } from "./GameManager";
 import { gatekeeper, LimiterType } from "./Gatekeeper";
 import { logger } from "./Logger";
-import { metrics } from "./WorkerMetrics";
+import { initWorkerMetrics } from "./WorkerMetrics";
 
 const config = getServerConfigFromServer();
 
@@ -34,10 +34,7 @@ export function startWorker() {
   const gm = new GameManager(config, log);
 
   if (config.otelEnabled()) {
-    // Set up periodic metrics updates
-    setInterval(() => {
-      metrics.updateGameMetrics(gm);
-    }, 15000); // Update every 15 seconds
+    initWorkerMetrics(gm);
   }
 
   // Middleware to handle /wX path prefix
diff --git a/src/server/WorkerMetrics.ts b/src/server/WorkerMetrics.ts
index 2f402a694..1576b0f73 100644
--- a/src/server/WorkerMetrics.ts
+++ b/src/server/WorkerMetrics.ts
@@ -10,14 +10,14 @@ import { getOtelResource } from "./OtelResource";
 
 dotenv.config();
 
-// Get server configuration
-const config = getServerConfigFromServer();
+export function initWorkerMetrics(gameManager: GameManager): void {
+  // Get server configuration
+  const config = getServerConfigFromServer();
 
-// Create resource with worker information
-const resource = getOtelResource();
+  // Create resource with worker information
+  const resource = getOtelResource();
 
-// Configure headers for basic auth if provided
-const getAuthHeaders = () => {
+  // Configure auth headers
   const headers = {};
   if (config.otelEnabled()) {
     headers["Authorization"] =
@@ -26,78 +26,67 @@ const getAuthHeaders = () => {
         "base64",
       );
   }
-  return headers;
-};
 
-// Create metrics exporter
-const metricExporter = new OTLPMetricExporter({
-  // Dummy endpoint if OTEL is not enabled to avoid parsing errors
-  url: `${config.otelEndpoint() || "https://dummy_endpoint.com"}/v1/metrics`,
-  headers: getAuthHeaders(),
-});
+  // Create metrics exporter
+  const metricExporter = new OTLPMetricExporter({
+    url: `${config.otelEndpoint()}/v1/metrics`,
+    headers,
+  });
 
-// Configure the metric reader
-const metricReader = new PeriodicExportingMetricReader({
-  exporter: metricExporter,
-  exportIntervalMillis: 15000, // Export metrics every 15 seconds
-});
+  // Configure the metric reader
+  const metricReader = new PeriodicExportingMetricReader({
+    exporter: metricExporter,
+    exportIntervalMillis: 15000, // Export metrics every 15 seconds
+  });
 
-// Create a meter provider
-const meterProvider = new MeterProvider({
-  resource,
-  readers: [metricReader],
-});
+  // Create a meter provider
+  const meterProvider = new MeterProvider({
+    resource,
+    readers: [metricReader],
+  });
 
-// Get meter for creating metrics
-const meter = meterProvider.getMeter("worker-metrics");
+  // Get meter for creating metrics
+  const meter = meterProvider.getMeter("worker-metrics");
 
-// Create OpenTelemetry metrics
-const activeGamesCounter = meter.createUpDownCounter(
-  "openfront.active_games.count",
-  {
-    description: "Number of active games on this worker",
-  },
-);
+  // Create observable gauges
+  const activeGamesGauge = meter.createObservableGauge(
+    "openfront.active_games.gauge",
+    {
+      description: "Number of active games on this worker",
+    },
+  );
 
-const connectedClientsCounter = meter.createUpDownCounter(
-  "openfront.connected_clients.count",
-  {
-    description: "Number of connected clients on this worker",
-  },
-);
+  const connectedClientsGauge = meter.createObservableGauge(
+    "openfront.connected_clients.gauge",
+    {
+      description: "Number of connected clients on this worker",
+    },
+  );
 
-const memoryUsageObservable = meter.createObservableGauge(
-  "openfront.memory_usage.bytes",
-  {
-    description: "Current memory usage of the worker process in bytes",
-  },
-);
+  const memoryUsageGauge = meter.createObservableGauge(
+    "openfront.memory_usage.bytes",
+    {
+      description: "Current memory usage of the worker process in bytes",
+    },
+  );
 
-// Register callback for the memory usage observable
-memoryUsageObservable.addCallback((result) => {
-  const memoryUsage = process.memoryUsage();
-  result.observe(memoryUsage.heapUsed);
-});
+  // Register callback for active games metric
+  activeGamesGauge.addCallback((result) => {
+    const count = gameManager.activeGames();
+    result.observe(count);
+  });
 
-// Export the metrics for use in the worker
-export const metrics = {
-  // Function to update game-related metrics
-  updateGameMetrics: (gameManager: GameManager) => {
-    console.log("Updating game metrics");
-    // Get the current counts
-    const currentActiveGames = gameManager.activeGames();
-    const currentActiveClients = gameManager.activeClients();
+  // Register callback for connected clients metric
+  connectedClientsGauge.addCallback((result) => {
+    const count = gameManager.activeClients();
+    result.observe(count);
+  });
 
-    // Set the absolute values (createUpDownCounter allows setting absolute values)
-    activeGamesCounter.add(currentActiveGames);
-    connectedClientsCounter.add(currentActiveClients);
+  // Register callback for memory usage metric
+  memoryUsageGauge.addCallback((result) => {
+    const memoryUsage = process.memoryUsage();
+    result.observe(memoryUsage.heapUsed);
+  });
 
-    // Memory metrics are automatically collected by the observable
-  },
-
-  // Expose the meter provider for potential additional metrics
-  meterProvider,
-
-  // Expose the meter for creating additional metrics
-  meter,
-};
+  console.log("Metrics initialized with GameManager");
+}