Add partial code

README.md

@@ -9,6 +9,8 @@
 ```
 
 Redis
+- use pool
+Tests
 Dockerize
 CI/CD
 Kubernetes

package.json

@@ -12,7 +12,8 @@
   },
   "dependencies": {
     "dotenv": "^8.2.0",
-    "express": "^4.17.1"
+    "express": "^4.17.1",
+    "ioredis": "4.16.0" 
   },
   "devDependencies": {
     "eslint": "^6.6.0",

src/app.js

@@ -3,8 +3,8 @@
 
 const express = require('express');
 
-const { CONFIG } = require('./config');
-const { healthCheckRouter } = require('./controllers');
+const { CONFIG, REDIS_CONFIG } = require('./config');
+const { healthCheckRouter, AppController } = require('./controllers');
 
 const app = express();
 
@@ -20,6 +20,7 @@ app.get(['/', '/api'], function(req, res, next) {
 
 // Adding routes
 app.use(CONFIG['BASE_PATH'], healthCheckRouter);
+app.use(`${CONFIG['BASE_PATH']}/stats`, AppController.stats);
 
 // Adding 404 route
 app.get('*', (req, res) => {

src/config.js

@@ -8,6 +8,12 @@ const CONFIG = {
   TIMESTAMP: new Date().toTimeString()
 };
 
+const REDIS_CONFIG = {
+  HOST: process.env.REDIS_HOST,
+  PORT: process.env.REDIS_PORT || 6379
+}
+
 module.exports = {
-  CONFIG
+  CONFIG,
+  REDIS_CONFIG
 };

src/controllers/app.controller.js

@@ -0,0 +1,24 @@
+'use strict';
+
+const { CacheService } = require('../services');
+
+class AppController {
+
+  constructor() {
+    this.cacheService = new CacheService();
+  }
+
+  stats(req, res) {
+    const hits = this.cacheService.get('stats:hits') || 0;
+    res.json({
+      success: true,
+      message: `Stats-Hits: ${hits}`
+    });
+    this.cacheService.set('stats', hits + 1);
+  }
+
+}
+
+module.exports = {
+  AppController
+};

src/controllers/index.js

@@ -1,6 +1,7 @@
 'use strict';
 
 const { healthCheckRouter } = require('./health-check.controller');
+const { AppController } = require('./app.controller');
 
 module.exports = {
   healthCheckRouter

src/services/cache.service.js

@@ -0,0 +1,35 @@
+'use strict';
+
+const Redis = require('ioredis'); 
+
+const { REDIS_CONFIG } = require('../config');
+
+class CacheService {
+
+  constructor() {
+    // TODO: Have connection pooling and IoC
+    // this.redisConnection = redisConnection;
+    this.cache = new Redis({
+      HOST: REDIS_CONFIG.HOST,
+      PORT: REDIS_CONFIG.PORT
+    });
+  }
+
+  set(key, value) {
+    this.cache.set(key, value);
+  }
+
+  get(key) {
+    this.cache.get(key);
+  }
+
+  inc(key) {
+    this.cache
+        .pipeline();
+  }
+
+}
+
+module.exports = {
+  CacheService
+};

src/services/index.js

@@ -1,3 +1,7 @@
 'use strict';
 
-module.exports = { };
+const { CacheService } = require('./cache.service');
+
+module.exports = { 
+  CacheService
+};