CONFIGURATION.md

Project Configuration

The project is configured for TypeScript code as the primary focus while also allowing JavaScript code.

TypeScript

• npm install --save-dev typescript
• tsconfig.json

TypeScript is configured to process both TypeScript and JavaScript files, and transpile these to ES2015 (ES6).

References:

• https://www.typescriptlang.org/docs/handbook/migrating-from-javascript.html
• https://www.typescriptlang.org/tsconfig
• https://github.com/Microsoft/TypeScript/tree/main/lib

ES2020 Polyfills

• npm install --save core-js regenerator-runtime
• tsconfig.json

TypeScript is configured to target ES2020 libraries, which need to be polyfilled.

These polyfills are used in the code by including the following import statements:

import "core-js/stable";
import "regenerator-runtime/runtime";

This is done instead of using the deprecated @babel/polyfill, and also means that Babel isn't needed.

References:

• https://dev.to/michi/why-typescript-over-babel-is-so-much-easier-to-create-libraries-with-how-to-guide-39d5
• https://github.com/zloirock/core-js

crypto-js

• npm install --save crypto-js
• npm install --save-dev @types/crypto-js

References:

• https://cryptojs.gitbook.io/docs/

WebPack

• npm install --save-dev webpack webpack-cli
• npm install --save-dev ts-loader source-map-loader
• webpack.config.js
• package.json

WebPack is used to configured to process TypeScript and JavaScript files, with TypeScript files handled by ts-loader and JavaScript files having any source maps reprocessed by source-map-loader.

"build", "build-prod", "watch", "watch-prod", and "clean" commands are configured in package.json.

References:

• https://webpack.js.org/guides/getting-started/
• https://www.typescriptlang.org/docs/handbook/migrating-from-javascript.html

Jest

• npm install --save-dev jest ts-jest @types/jest
• npx ts-jest config:init creates default test.config.js
• tsconfig.json
• tests/tsconfig.json
• package.json

test.config.js is configured to process both TypeScript and JavaScript file types, in ESM without requiring Babel.

tsconfig.json is configured to enable esModuleInterop in order to quiet warnings.

tests/tsconfig.json customizes TypeScript processing of test files.

"test" and "test-watch" commands are configured in package.json.

References:

• https://jestjs.io/docs/getting-started#using-typescript
• https://kulshekhar.github.io/ts-jest/

WebSocket and WebRTC for Jest

• npm install --save-dev wrtc

This package provides WebSocket and WebRTC objects in the Node environment for Jest tests.

Sample Jest test code:

global.WebSocket = require("ws");
global.RTCPeerConnection = require("@koush/wrtc").RTCPeerConnection;

Note: If the ws module isn't found in a new set-up then use npm install --save-dev ws.

Linting

Set-Up

Set up:

• npm install --save-dev eslint @typescript-eslint/parser @typescript-eslint/eslint-plugin
• npm install --save-dev eslint-plugin-jest
• .eslintrc.js - TypeScript lint, ESLing, and Jest linting rules.
• .eslintignore
• tsconfig.json - Type checking rules.

Note that the versions of @typescript-eslint/parser and @typescript-eslint/eslint-plugin must be the same.

"lint" and "lint-path" commands are configured in package.json.

References:

• https://eslint.org/blog/2019/01/future-typescript-eslint
• https://github.com/typescript-eslint/typescript-eslint/blob/master/docs/getting-started/linting/README.md
• https://github.com/typescript-eslint/typescript-eslint/tree/master/packages/eslint-plugin
• https://eslint.org/docs/user-guide/configuring
• https://eslint.org/docs/rules/
• https://www.npmjs.com/package/eslint-plugin-jest
• https://www.typescriptlang.org/tsconfig#compilerOptions

JSDoc

Set up:

• npm install --save-dev jsdoc
• npm install --save-dev rimraf
• tsconfig.jsdoc.json
• /jsdoc
• package.json

JSDoc can't process files with TypeScript syntax so the documentation build process is to transpile the source to ECMAScript and then run JSDoc on that.

"devdoc" and "sdkdoc" commands are configured in package.json.

References:

• https://jsdoc.app/
• https://www.npmjs.com/package/jsdoc
• https://www.npmjs.com/package/rimraf