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Introduction The Event Loop is a crucial mechanism in JavaScript (used in both browsers and NodeJS runtime environments). Despite JavaScript being single-threaded, the Event Loop enables it to handle multiple asynchronous tasks (like ` setTimeout `, ` setInterval `, ` fetch `, etc.) efficiently, similar to how multi-threading works in other programming languages. Related Components Call Stack The Call Stack is a vital concept that explains how the JavaScript engine keeps track of function calls within a program. It operates on a Last In, First Out (LIFO) structure, meaning the last function called is the first one to be executed. When a function is called, it's added to the Call Stack . Once the function completes execution, it's removed from the Call Stack. This process helps JavaScript execute tasks sequentially, in the order functions are called. Task Queue The Task Queue (also known as the Callback Queue , Event Queue , or Macrotask Queue ) contains JavaScript task...

Introduction The Facade is a structural design pattern . It helps create a simple intermediary object that interacts with multiple systems (such as subsystems ). The responsibilities of the Facade Pattern include: Simplifying complex interactions with systems through the intermediary Facade object. Hiding the complex internal operations of subsystems, making them easier to use. Frequency of use: quite high. Problem and solution In cases where some processes require interaction with multiple services or third-party systems, and these processes are needed repeatedly in various places within the system, the typical solution might be to copy and paste the logic to those places. However, this leads to duplicated code in many locations, making maintenance and updates difficult when there are changes. The solution is to use the Facade Pattern to create an intermediary object to communicate with subsystems. This allows for the implementation of complex logic in a centralized and well-defin...

Introduction Moleculer is a fast, modern, and powerful microservices framework for NodeJS . It helps build efficient, reliable, and highly scalable services. Originally designed for JavaScript , Moleculer now supports Typescript and offers a CLI tool that creates boilerplates as easily as Nest , Next , Vite React , and Angular. Implementing in an Existing NodeJS Project If you already have a NodeJS project and want to integrate Moleculer , it's simple. Just install the package and use the provided APIs . yarn add moleculer To create a service like this: import { ServiceBroker } from 'moleculer' const broker = new ServiceBroker () broker . createService ({ name: 'math' , actions: { add ( ctx ) { return Number ( ctx . params . a ) + Number ( ctx . params . b ) }, }, }) broker . start () . then (() => broker . call ( 'math.add' , { a: 1 , b: 2 })) . then (( res : number ) => console . log ( '1 + 2 =' ...