From 83e8c44d98b5ce52ff3345bd45e7487d79c38d3f Mon Sep 17 00:00:00 2001
From: Bojan Kucera <boki@stare.gg>
Date: Thu, 5 Jun 2025 09:24:25 -0400
Subject: [PATCH] improved logger and added shutdown handler

---
 apps/data-service/src/index.ts      |   4 +-
 libs/logger/src/gracefulShutdown.ts | 116 ++++++++++++++++++++++++++++
 libs/logger/src/index.ts            |   2 +
 libs/utils/tsconfig.json            |   3 +-
 4 files changed, 123 insertions(+), 2 deletions(-)
 create mode 100644 libs/logger/src/gracefulShutdown.ts

diff --git a/apps/data-service/src/index.ts b/apps/data-service/src/index.ts
index a2f9fa7..ffcbeee 100644
--- a/apps/data-service/src/index.ts
+++ b/apps/data-service/src/index.ts
@@ -1,7 +1,7 @@
 /**
  * Data Service - Combined live and historical data ingestion
  */
-import { createLogger } from '@stock-bot/logger';
+import { createLogger, GracefulShutdownManager } from '@stock-bot/logger';
 import { loadEnvVariables } from '@stock-bot/config';
 import { Hono } from 'hono';
 import { serve } from '@hono/node-server';
@@ -11,6 +11,8 @@ loadEnvVariables();
 
 const app = new Hono();
 const logger = createLogger('data-service');
+const shutdownManager = new GracefulShutdownManager(logger);
+
 const PORT = parseInt(process.env.DATA_SERVICE_PORT || '3002');
 // Health check endpoint
 app.get('/health', (c) => {
diff --git a/libs/logger/src/gracefulShutdown.ts b/libs/logger/src/gracefulShutdown.ts
new file mode 100644
index 0000000..ef2d783
--- /dev/null
+++ b/libs/logger/src/gracefulShutdown.ts
@@ -0,0 +1,116 @@
+import pino from 'pino';
+
+interface ShutdownHandler {
+  name: string;
+  handler: () => Promise<void> | void;
+  timeout?: number;
+}
+
+export class GracefulShutdownManager {
+  private logger: pino.Logger;
+  private handlers: ShutdownHandler[] = [];
+  private isShuttingDown = false;
+  private startTime = Date.now();
+
+  constructor(logger: pino.Logger) {
+    this.logger = logger;
+    this.setupSignalHandlers();
+  }
+
+  /**
+   * Register a shutdown handler
+   */
+  addHandler(handler: ShutdownHandler): void {
+    this.handlers.push(handler);
+  }
+
+  /**
+   * Setup signal handlers for graceful shutdown
+   */
+  private setupSignalHandlers(): void {
+    // Graceful shutdown signals
+    process.on('SIGTERM', () => this.shutdown('SIGTERM', 0));
+    process.on('SIGINT', () => this.shutdown('SIGINT', 0));
+    process.on('SIGUSR2', () => this.shutdown('SIGUSR2', 0)); // nodemon
+
+    // Fatal error handlers
+    process.on('uncaughtException', (error) => {
+      this.logger.error('Uncaught exception', error, { fatal: true });
+      this.shutdown('uncaughtException', 1);
+    });
+
+    process.on('unhandledRejection', (reason, promise) => {
+      this.logger.error('Unhandled promise rejection', {
+        reason: reason instanceof Error ? reason.message : reason,
+        stack: reason instanceof Error ? reason.stack : undefined,
+        fatal: true
+      });
+      this.shutdown('unhandledRejection', 1);
+    });
+
+    // Process warnings
+    process.on('warning', (warning) => {
+      this.logger.warn('Process warning', {
+        name: warning.name,
+        message: warning.message,
+        stack: warning.stack
+      });
+    });
+
+    // Final exit
+    process.on('exit', (code) => {
+      const uptime = Date.now() - this.startTime;
+      console.log(`Process exiting with code ${code} after ${uptime}ms`);
+    });
+  }
+
+  /**
+   * Execute graceful shutdown
+   */
+  private async shutdown(signal: string, exitCode: number): Promise<void> {
+    if (this.isShuttingDown) {
+      this.logger.warn('Force shutdown - multiple signals received');
+      process.exit(1);
+    }
+
+    this.isShuttingDown = true;
+    const shutdownStart = Date.now();
+
+    this.logger.info('Graceful shutdown initiated', {
+      signal,
+      exitCode,
+      uptime: Date.now() - this.startTime,
+      memoryUsage: process.memoryUsage(),
+      handlersCount: this.handlers.length
+    });
+
+    // Execute shutdown handlers
+    for (const handler of this.handlers) {
+      try {
+        this.logger.info(`Executing shutdown handler: ${handler.name}`);
+        const timeout = handler.timeout || 5000;
+        
+        await Promise.race([
+          Promise.resolve(handler.handler()),
+          new Promise((_, reject) => 
+            setTimeout(() => reject(new Error(`Timeout after ${timeout}ms`)), timeout)
+          )
+        ]);
+        
+        this.logger.info(`Shutdown handler completed: ${handler.name}`);
+      } catch (error) {
+        this.logger.error(`Shutdown handler failed: ${handler.name}`, error);
+      }
+    }
+
+    const shutdownDuration = Date.now() - shutdownStart;
+    this.logger.info('Graceful shutdown completed', {
+      signal,
+      shutdownDuration,
+      totalUptime: Date.now() - this.startTime
+    });
+
+    // Give logs time to flush
+    setTimeout(() => process.exit(exitCode), 100);
+  }
+}
\ No newline at end of file
diff --git a/libs/logger/src/index.ts b/libs/logger/src/index.ts
index 8a5eb8a..af7bfd4 100644
--- a/libs/logger/src/index.ts
+++ b/libs/logger/src/index.ts
@@ -45,3 +45,5 @@ export type {
 } from './types';
 
 export type { LoggingMiddlewareOptions } from './middleware';
+
+export { GracefulShutdownManager } from './gracefulShutdown';
diff --git a/libs/utils/tsconfig.json b/libs/utils/tsconfig.json
index 296ca8c..4ad4f6c 100644
--- a/libs/utils/tsconfig.json
+++ b/libs/utils/tsconfig.json
@@ -7,5 +7,6 @@
   },
   "include": [
     "src/**/*"
-  ],  "exclude": ["node_modules", "dist", "**/*.test.ts", "**/*.spec.ts"]
+  ],
+  "exclude": ["node_modules", "dist", "**/*.test.ts", "**/*.spec.ts"],
 }