feat(#36): create scaler emitter to handle scaling down services

Co-authored-by: nukdown <belchior.emanoel@gmail.com>

events/scalerEmmiter.js

@@ -0,0 +1,24 @@
+'use strict'
+
+const EventEmitter = require('events')
+
+class ScaleEmitter extends EventEmitter {
+  constructor() {
+    super()
+		this._eventRelease = 'releaseService'
+    this.on(this._eventRelease, this.scaleDownServices)
+  }
+
+	scaleDownServices(serviceName, servicePool) {
+		if(servicePool.servicesList[serviceName].length > 1) {
+      console.log('Releasing service')
+			delete servicePool.servicesList[serviceName].pop()
+		}
+	}
+
+  emit(serviceName, servicePool) {
+    super.emit(this._eventType, serviceName, servicePool)
+  }
+}
+
+module.exports = ScaleEmitter

lib/service.js

@@ -2,6 +2,7 @@
 
 const axios = require('axios');
 const EventEmitter = require('events')
+const ScaleEmitter = require('../events/scalerEmmiter.js')
 
 class Service {
   constructor(name, baseUrl) {
@@ -16,10 +17,8 @@ class Service {
 
 class ServicePool  {
 	constructor(servicesInfos){
-		this.emitter = new EventEmitter()
+		this.emitter = new ScaleEmitter()
 		this.servicesInfos = servicesInfos
-		this._eventRelease = 'releaseService'
-		this.emitter.on(this._eventRelease, this.scaleDownServices)
 		this.availableServices = Object.keys(servicesInfos)
 		this.servicesList = {}
 
@@ -34,6 +33,7 @@ class ServicePool  {
 	acquire(serviceName) {
 		if(this.servicesList[serviceName].length === 0){
 			if(this.servicesInfos[serviceName] !== undefined) {
+				console.log('Creating new service')
 				let s = new Service(serviceName, servicesInfos[service])
 				this.servicesList[service].push(s)
 			}
@@ -43,14 +43,9 @@ class ServicePool  {
 
 	release(service) {
 		this.servicesList[service.name].push(service)
-		this.emitter.emit(this._eventRelease, service.name, this)
+		this.emitter.emit(service.name, this)
 	}
 
-	scaleDownServices(serviceName, servicePool) {
-		if(servicePool.servicesList[serviceName].length > 1) {
-			delete servicePool.servicesList[serviceName].pop()
-		}
-	}
 }
 
 module.exports = {