chore: Implement logger with winston library

packages/backend/.env-example

@@ -1 +1,2 @@
 PORT=3000
+APP_ENV=development

packages/backend/package.json

@@ -13,7 +13,8 @@
     "dotenv": "^10.0.0",
     "express": "~4.16.1",
     "http-errors": "~1.6.3",
-    "morgan": "~1.9.1"
+    "morgan": "^1.10.0",
+    "winston": "^3.3.3"
   },
   "contributors": [
     {

packages/backend/src/app.ts

@@ -1,14 +1,15 @@
-import appEnv from './config/app-env'
+import appConfig from './config/app'
 import createError from 'http-errors';
 import express, { Request, Response, NextFunction } from 'express';
-import logger from 'morgan';
+import logger from './helpers/logger';
+import morgan from './helpers/morgan';
 
 import indexRouter from './routes/index';
 
 const app = express();
-const port = appEnv.port;
+const port = appConfig.port;
 
-app.use(logger('dev'));
+app.use(morgan);
 app.use(express.json());
 app.use(express.urlencoded({ extended: false }));
 
@@ -31,5 +32,5 @@ app.use(function(err: any, req: Request, res: Response, _next: NextFunction) {
 });
 
 app.listen(port, () => {
-  return console.log(`Server is listening on ${port}`)
+  logger.info(`Server is listening on ${port}`)
 })

packages/backend/src/config/app-env.ts

@@ -1,12 +0,0 @@
-import * as dotenv from 'dotenv';
-dotenv.config();
-
-type AppEnv = {
-  port: string,
-}
-
-const appEnv: AppEnv = {
-  port: process.env.PORT || '3000',
-}
-
-export default appEnv;

packages/backend/src/config/app.ts

@@ -0,0 +1,14 @@
+import * as dotenv from 'dotenv';
+dotenv.config();
+
+type AppConfig = {
+  port: string,
+  appEnv: string,
+}
+
+const appConfig: AppConfig = {
+  port: process.env.PORT || '3000',
+  appEnv: process.env.APP_ENV || 'development',
+}
+
+export default appConfig;

packages/backend/src/helpers/logger.ts

@@ -0,0 +1,50 @@
+import winston from 'winston'
+import appConfig from '../config/app'
+
+const levels = {
+  error: 0,
+  warn: 1,
+  info: 2,
+  http: 3,
+  debug: 4,
+}
+
+const level = () => {
+  return appConfig.appEnv === 'development' ? 'debug' : 'warn'
+}
+
+const colors = {
+  error: 'red',
+  warn: 'yellow',
+  info: 'green',
+  http: 'magenta',
+  debug: 'white',
+}
+
+winston.addColors(colors)
+
+const format = winston.format.combine(
+  winston.format.timestamp({ format: 'YYYY-MM-DD HH:mm:ss:ms' }),
+  winston.format.colorize({ all: true }),
+  winston.format.printf(
+    (info) => `${info.timestamp} [${info.level}]: ${info.message}`,
+  ),
+)
+
+const transports = [
+  new winston.transports.Console(),
+  new winston.transports.File({
+    filename: 'logs/error.log',
+    level: 'error',
+  }),
+  new winston.transports.File({ filename: 'logs/server.log' }),
+]
+
+const logger = winston.createLogger({
+  level: level(),
+  levels,
+  format,
+  transports,
+})
+
+export default logger

packages/backend/src/helpers/morgan.ts

@@ -0,0 +1,14 @@
+import morgan, { StreamOptions } from 'morgan';
+
+import logger from './logger';
+
+const stream: StreamOptions = {
+  write: (message) => logger.http(message.substring(0, message.lastIndexOf('\n')))
+};
+
+const morganMiddleware = morgan(
+  ":method :url :status :res[content-length] - :response-time ms",
+  { stream }
+);
+
+export default morganMiddleware;