Setup configurations for nodejs and typescript

• Initialize npm and add your details

npm init -y

• Add typescript, ts-node and @types/node definitions to dev dependencies.

$ npm i --save-dev typescript
$ npm i --save-dev ts-node
$ npm i --sav-dev @types/node

• Add the default TypeScript configuration file

$ npx tsc --init 

Common output directory names include dist, build, prod, and server.

This config file is also where you can tell TypeScript how strict it should be while checking your code and what to ignore. If you're moving a project to TypeScript, you can gracefully integrate TS by working with the settings in this config file.

To use TypeScript, you need to add a script to your package.json file to compile TypeScript to JavaScript. This is generally called your "build" script but could be named anything.

• Add a build script to your package.json file

"scripts": {
    "build": "npx tsc"
  },

To execute your "build" script use the following:

$ npm run build

Video Demonstration

{
  "compilerOptions": {
    "target": "es5",                          
    "module": "commonjs",                     
    "lib": ["ES2018", "DOM"], 
    "outDir": "./build",                        
    "strict": true,                           
    "noImplicitAny": true,                 
  },
  "exclude": ["node_modules", "./build", "*/__test__/**"]
}

You will see many more options available than what is above. Your application may require additional settings to be configured, but these are typically the main settings to start with.

• target - sets what version of JS TypeScript will be transpiled to.
• module - sets what module system will be used when transpiling. Node.js uses the common.js module system by default.
• lib - is used to say what libraries your code is using. In this case, ES2018 and the DOM API.
• outDir - where you want your src code to output to. Often named build, prod, or server (when using it serverside).
• strict - enable strict typing.
• noImplicitAny - disallow the "any" type (covered in TypeScript Basics).
• exclude - directories to exclude in compiling.

• Catch up on ES6 modules if you haven't had the opportunity to work with them yet.
• Official documentation from Microsoft on installing TypeScript.
• Explicit instructions from Microsoft on Installing TypeScript and working with NPM and a text editor.