Last time we were talking about CLI in Node.js , let’s see how one of the essential parts of the technology works internally. The topic for this article is to overview the Node.js Event Loop concept and see the program examples using the Node.js Event-Driven applications design paradigm.

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Awesome Node.js Event Loop Phases

Event Loop

Event Loop is a program, which allows subscribing to system resource events. It provides a callback stack that can be linked to resources and executed when appropriate descriptors are ready.

The Event Loop abstraction might be already known to JavaScript developers as the concept is widely used in programming applications for browsers. …

The first part of Web Components overview is about the Custom Elements standard.

Shadow DOM

The Shadow DOM specifications bring a scope concept to Web styles’ definitions. Those scopes are implemented through multiple DOM trees, embedded into a single document. In some way, the Shadow DOM's approach can be compared with the iframe element inside a document, as it has a naturally-isolated DOM structure. In terms of documents, the Shadow DOM's definitions are spread between several different standards, like DOM specification, HTML specification, CSS Scoping Module, UI Events, etc.

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Web Components

The DOM specification defines a model for node trees and how nodes communicate with each other through events. The DOM node tree is a hierarchical structure of nodes, where some nodes can branch out, while others are just leaves. The specification differentiates Document Tree and Shadow Tree via the connection to their roots. The document object is the root of the Document Tree, while for the Shadow Tree a special type of root is proposed which is called the Shadow Root. The Shadow Root must be attached to any other tree under the host element. The Shadow Root can be thought of as a Document Fragment - the specification defines a belonging relationship between two interfaces. …

A 5th sprint change for the educational JavaScript project will happen this Sunday, 8th of September, 1pm CET. The planned agenda for the meeting would be:

  • Introduce the Educational JavaScript Note Project
  • The architectural overview
  • Workshop preparations

Of course like in the previous sprint change (be careful, it’s in Russian 😂), we also shall go through the agenda:

Previous sprint change meeting notes can be found here.

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Abstract Art on JavaScript Frameworks

Which in the best scenario takes around 1 hour.

  • Are you looking for experience in JavaScript?
  • Do you want to participate in the open-source project, developed step by step in Agile methodology? …


Alex Korzhikov

Software engineer, instructor, mentor, and author of technical materials #JavaScript

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