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Node.js 8 has what important features and fixes, I believe that many inexperienced people are helpless about this, for this reason this article summarizes the causes and solutions of the problem, through this article I hope you can solve this problem.

Async Hooks API Introduction

The Async Hooks (formerly known as AsyncWrap) API allows you to get structural trace information about the lifecycle of a handle object.

The message sent by the API informs the consumer of the lifecycles of all handle objects in Node.js. It tries to solve problems like continuation-local-storage npm package.

If you're using continuation-local-storage, you can already use async hooks called cls-hooks instead-it's just not the best time to use async hooks right now, so use them carefully!

How the Async Hooks API works in Node.js 8

The registration function of the createHooks function is invoked by different lifecycle events for each asynchronous operation.

const asyncHooks = require('async_hooks')asyncHooks.createHooks({ init, pre, post, destroy})

Learn more about Async Hooks, or check out the documentation of work in progress. These functions are selectively triggered based on lifecycle events of the handler object.

N-API Introduction

N-API is the API used to build native plugins. It is independent of the underlying JavaScript runtime and maintained as part of Node.js itself. The goal is to ensure that the application binary interface (ABI) remains stable across different versions of Node.js.

The purpose of the N-API is to separate add-ons from changes in the base JavaScript engine so that native plugins can run different versions of Node.js without having to recompile.

Learn more about N-API.

Buffer security improvements in Node.js 8

Prior to Node.js version 8, buffers allocated using the new Buffer(Number) constructor did not use ZEROS to initialize memory space. As a result, new Buffer instances may contain sensitive information, which can easily lead to security issues.

Although this is a decision to improve the performance of creating new buffers, it is not intended for most people. So starting with Node.js 8, Buffers assigned with new Buffer(Number) or Buffer(Number) are automatically populated by ZEROS.

Upgrade V8 to 5.8: TurboFan& Intention

With Node.js version 8, the underlying V8 JavaScript engine is updated as well.

For Node.js users, the biggest change is the introduction of TurboFan and Ignition. Ignition is the interpreter for V8 and TurboFan is the optimizing compiler.

"The combined use of Ignition and TurboFan has been developed for nearly three years. In 2010, it represented the end result of the V8 team's collective understanding of JavaScript's measured performance and careful analysis of Full-codegen's shortcomings and Crankshaft. This is also the basis for continuing to optimize the JavaScript language architecture in the years ahead. " - Daniel Clifford and the V8 team

The current V8 compilation pipeline is shown below.

The biggest problem with this pipeline is that new language features have to be implemented in different parts of the pipeline, which adds a lot of extra development effort.

Below is a simplified pipeline without the FullCode Generator and Crankshaft:

The new pipeline significantly reduces the technical burden on the V8 team and enables many improvements that were previously impossible to achieve.

Learn more about TurboFan and Ignition and TurboFan Inlining Heuristics.

Upgrade npm to 5.0.0

The new Node.js 8 version also comes with npm 5 -the latest version of npm CLI.

Highlights of the new npm version:

A new standardized lock file feature for cross-package manager compatibility (package-lock.json), and a new format and semantics for shrinkwrap

--save is no longer needed because all installations will be saved by default

node-gyp now supports node-gyp.cmd for Windows

The new release will include sha512 and sha1 checksums

Other notable changes in Node.js 8 Buffer

Buffer method now accepts Uint8Array as input

Child Process

Improved Argument and Kill signal validation

The Child Process method accepts Uint8Array as input

Console

Error event sending is now suppressed when using console methods

Domains

Native Promise instances are now domain aware

file system

Utility class fs.SyncWriteStream deprecated

The deprecated fs.read( ) string interface has been removed

HTTP

Overflow Cookie headers are concatenated into a string

The httpResponse.writeHeader( ) method has been deprecated

Stream

Stream now supports destroy( ) and_destroy( ) APIs

TLS

The reject Unauthorized option now defaults to true

URL

WHATWG URL implementation, now fully supported by Node.js API

After reading the above content, do you know what important functions and repair methods Node.js8 has? If you still want to learn more skills or want to know more related content, welcome to pay attention to the industry information channel, thank you for reading!

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