add counter implementaiton with async-redis

package.json

@@ -4,7 +4,7 @@
   "description": "Minimal API for counting clicks",
   "main": "index.js",
   "dependencies": {
-    "ioredis": "^4.1.0",
+    "async-redis": "^1.1.4",
     "koa": "^2.5.3",
     "koa-json": "^2.0.2",
     "koa-router": "^7.4.0"

src/counter.js

@@ -1,14 +1,20 @@
-//const Redis = require('ioredis')
-//const redis = new Redis()
+class Counter {
+  constructor(redis) {
+    this.redis = redis
+    /* make sure we don't miss errors */
+    this.redis.on("error", (err) => { console.log("Error: " + err) })
+  }
 
-var COUNTER = 0
+  async incr (val) {
+    /* default to incrementing by one */
+    val = val == undefined ? 1 : val
+    /* increment */
+		this.redis.incr('default')
+  }
   
-exports.incr = (val) => {
-  /* default to incrementing by one */
-  val = val == undefined ? 1 : val
-  COUNTER += val
+  async state () {
+    return await this.redis.get('default')
+  }
 }
 
-exports.state = () => {
-  return COUNTER
-}
+module.exports = Counter

src/index.js

@@ -1,22 +1,27 @@
 const Koa = require('koa')
 const Router = require('koa-router')
 const JSON = require('koa-json')
-const Counter = require('./counter')
 
+const Counter = require('./counter')
+const Redis = require('async-redis')
 
 /* DEFAULTS */
-let LISTEN_PORT = 3000
+const REDIS_HOST = 'localhost'
+const REDIS_PORT = 6379
+const LISTEN_PORT = 3000
 
 const app = new Koa()
 const router = new Router()
+const redis = Redis.createClient(REDIS_PORT, REDIS_HOST)
+const counter = new Counter(redis)
 
 router.put('/click', async ctx => {
-    Counter.incr()
-    ctx.body = { 'counter': Counter.state() }
+    counter.incr()
+    ctx.body = { 'counter': await counter.state() }
 });
 
 router.get('/clicks', async ctx => {
-    ctx.body = { 'counter': Counter.state() }
+    ctx.body = { 'counter': await counter.state() }
 });
 
 app.use(JSON({pretty: true}))