logging

package.json

@@ -24,7 +24,9 @@
   "dependencies": {
     "axios": "^0.21.1",
     "dotenv": "^10.0.0",
-    "express": "^4.17.1"
+    "express": "^4.17.1",
+    "winston": "^latest_version",
+    "express-winston": "^latest_version"
   },
   "devDependencies": {
     "chai": "^4.3.8",

src/config/logger.js

@@ -0,0 +1,19 @@
+import winston from 'winston';
+
+const logger = winston.createLogger({
+  level: 'info',
+  format: winston.format.json(),
+  defaultMeta: { service: 'user-service' },
+  transports: [
+    new winston.transports.File({ filename: 'error.log', level: 'error' }),
+    new winston.transports.File({ filename: 'combined.log' })
+  ]
+});
+
+// If we're not in production, log to the `console` with the format:
+// `${info.level}: ${info.message} JSON.stringify({ ...rest }) `
+if (process.env.NODE_ENV !== 'production') {
+  logger.add(new winston.transports.Console({
+    format: winston.format.simple()
+  }));
+}

src/index.js

@@ -2,10 +2,14 @@
 import express from 'express';
 import axios from 'axios';
 import crypto from 'crypto';
+import express from 'express';
+import { logger } from './config/logger';
+import { requestLogger, errorLogger } from './middlewares/loggingMiddleware';
 import dotenv from 'dotenv';
 dotenv.config();
 
 const app = express();
+app.use(requestLogger);
 const PORT = 3000;
 
 // Access environment variables
@@ -156,8 +160,11 @@ app.post('/handleWebhook', async (req, res) => {
     if (!transactionSuccess) {
         console.error(`Failed to process transaction after ${MAX_RETRIES} retries.`);
     }
+
+    app.use(errorLogger);
+
 });
 
 app.listen(PORT, () => {
-    console.log(`Server is running on http://localhost:${PORT}`);
+    logger.info(`Server is running on http://localhost:${PORT}`);
 });

src/middlewares/loggingMiddleware.js

@@ -0,0 +1,30 @@
+import expressWinston from 'express-winston';
+
+// Request logger middleware
+app.use(expressWinston.logger({
+  transports: [
+    new winston.transports.Console()
+  ],
+  format: winston.format.combine(
+    winston.format.colorize(),
+    winston.format.json()
+  ),
+  meta: true, // optional: control whether you want to log the meta data about the request (default to true)
+  msg: "HTTP {{req.method}} {{req.url}}", // optional: customize the default logging message. E.g. "{{res.statusCode}} {{req.method}} {{res.responseTime}}ms {{req.url}}"
+  expressFormat: true, // Use the default Express/morgan request formatting. Enabling this will override any msg if true. Will only output colors with colorize set to true
+  colorize: false, // Color the text and status code, using the Express/morgan color palette (default green, 3XX cyan, 4XX yellow, 5XX red).
+  ignoreRoute: function (req, res) { return false; } // optional: allows to skip some log messages based on request and/or response
+}));
+
+// Your routes go here
+
+// Error logger middleware (should be after all your routes)
+app.use(expressWinston.errorLogger({
+  transports: [
+    new winston.transports.Console()
+  ],
+  format: winston.format.combine(
+    winston.format.colorize(),
+    winston.format.json()
+  )
+}));