Add performance monitoring (prometheus for metrics and winston for logging)

package.json

@@ -23,7 +23,8 @@
     "build/public"
   ],
   "scripts": {
-    "dev": "wrangler dev src/index.ts",
+    "uninstall-workerd-unsupported-packages": "npm uninstall winston winston-loki prom-client --no-save",
+    "dev": "npm run dev:workerd",
     "dev:node": "tsx src/start-server.ts",
     "dev:workerd": "wrangler dev src/index.ts",
     "deploy": "wrangler deploy --minify src/index.ts",
@@ -53,6 +54,9 @@
     "hono": "^4.6.10",
     "jose": "^6.0.11",
     "patch-package": "^8.0.0",
+    "prom-client": "^15.1.3",
+    "winston": "^3.18.3",
+    "winston-loki": "^6.1.3",
     "ws": "^8.18.0",
     "zod": "^3.22.4"
   },

src/apm/console/logger.ts

@@ -0,0 +1,7 @@
+import { createLogger, transports, format } from 'winston';
+
+export const ConsoleLogger = createLogger({
+  transports: [new transports.Console()],
+  format: format.combine(format.simple(), format.colorize()),
+  level: 'debug',
+});

src/apm/index.ts

@@ -0,0 +1,12 @@
+import { Environment } from '../utils/env.js';
+
+let _logger: any;
+
+if (Environment().APM_LOGGER === 'loki') {
+  const { LokiLogger } = await import('./loki/logger.js');
+  _logger = LokiLogger;
+} else {
+  _logger = console;
+}
+
+export const logger = _logger;

src/apm/loki/envConfig.ts

@@ -0,0 +1,21 @@
+import { Environment } from '../../utils/env';
+
+const requiredEnvVars = ['NODE_ENV', 'SERVICE_NAME', 'LOKI_AUTH', 'LOKI_HOST'];
+
+export const loadAndValidateEnv = () => {
+  const env = Environment({}) as Record<string, string>;
+  requiredEnvVars.forEach((varName) => {
+    if (!env[varName]) {
+      console.error(`Missing required environment variable: ${varName}`);
+      process.exit(1);
+    }
+  });
+
+  return {
+    NODE_ENV: env.NODE_ENV!,
+    SERVICE_NAME: env.SERVICE_NAME!,
+    LOKI_AUTH: env.LOKI_AUTH!,
+    LOKI_HOST: env.LOKI_HOST!,
+    LOKI_PUSH_ENABLED: env.LOKI_PUSH_ENABLED!,
+  };
+};

src/apm/loki/logger.ts

@@ -0,0 +1,35 @@
+const { loadAndValidateEnv } = await import('./envConfig.js');
+
+let LokiLogger: any;
+
+try {
+  const { createLogger, transports, format } = await import('winston');
+  const LokiTransport = await import('winston-loki');
+
+  const envVars = loadAndValidateEnv();
+
+  LokiLogger = createLogger({
+    transports: [
+      ...(envVars.LOKI_PUSH_ENABLED === 'true'
+        ? [
+            new LokiTransport({
+              host: envVars.LOKI_HOST,
+              basicAuth: envVars.LOKI_AUTH,
+              labels: { app: envVars.SERVICE_NAME, env: envVars.NODE_ENV },
+              json: true,
+              format: format.json(),
+              replaceTimestamp: true,
+              onConnectionError: (err) => console.error(err),
+            }),
+          ]
+        : []),
+      new transports.Console({
+        format: format.combine(format.simple(), format.colorize()),
+      }),
+    ],
+  });
+} catch (error) {
+  LokiLogger = null;
+}
+
+export { LokiLogger };

src/apm/prometheus/envConfig.ts

@@ -0,0 +1,26 @@
+import { Environment } from '../../utils/env';
+
+const requiredEnvVars = [
+  'NODE_ENV',
+  'SERVICE_NAME',
+  'PROMETHEUS_GATEWAY_URL',
+  'PROMETHEUS_GATEWAY_AUTH',
+];
+
+export const loadAndValidateEnv = (): { [key: string]: string } => {
+  const env = Environment({}) as Record<string, string>;
+  requiredEnvVars.forEach((varName) => {
+    if (!env[varName]) {
+      console.error(`Missing required environment variable: ${varName}`);
+      process.exit(1);
+    }
+  });
+
+  return {
+    NODE_ENV: env.NODE_ENV!,
+    SERVICE_NAME: env.SERVICE_NAME!,
+    PROMETHEUS_GATEWAY_URL: env.PROMETHEUS_GATEWAY_URL!,
+    PROMETHEUS_GATEWAY_AUTH: env.PROMETHEUS_GATEWAY_AUTH!,
+    PROMETHEUS_PUSH_ENABLED: env.PROMETHEUS_PUSH_ENABLED!,
+  };
+};