nodejs_typescript_setup

nodejs_typescript_setup

Install typescript

sudo npm install -g typescript

After install, we can check

C:\dev\github>tsc --version Version 3.8.3

Create file app.ts

C:\dev\github\nodejs_typescript_setup>tsc app.ts

This generates app.js file in the same folder

TO constantly watch the file. C:\dev\github\nodejs_typescript_setup>tsc app.ts -w

Not to do this, ideally, generate a config. So do a tsc --init THis will generate a tsconfig.json

In this file, enable outdir, rootdir for output js and source ts files respectively.

Most importantly, need to enable,

"moduleResolution": "node", /_ Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). _/

Now, to compile, just do tsc no file name etc required, as it will pickup config file.

---

Node setup

npm init

Install regular express

npm install express --save

Rest install dev dependencies

nodejs_typescript_setup>npm i -D typescript ts-node nodemon @types/node @types/express

These are specific node and express based types.

Create scripts in package.json

"scripts" {"start": "node dist/app.js", "dev": "nodemon src/app.ts", "build": "tsc -p ."}

---

Code setup

in app.ts,

we can import because of typescript instead of require etc

import express from "express";

Write code with endpoints etc

npm run dev

C:\dev\github\nodejs_typescript_setup>npm run dev

> nodejs_typescript_setup@1.0.0 dev C:\dev\github\nodejs_typescript_setup
> nodemon src/app.ts

[nodemon] 2.0.3
[nodemon] to restart at any time, enter `rs`
[nodemon] watching path(s): _._
[nodemon] watching extensions: ts,json
[nodemon] starting `ts-node src/app.ts`
Server running...
`

ANd http://127.0.0.1:5000/ this will return hello

Also, when dev is done, to actually build

C:\dev\github\nodejs_typescript_setup>npm run build

> nodejs_typescript_setup@1.0.0 build C:\dev\github\nodejs_typescript_setup
> tsc -p .

This will create js in dist folder. It will use arrow function etc depending on es5 or es6 as target etc.

To, run the normal js as start

C:\dev\github\nodejs_typescript_setup>npm start

> nodejs_typescript_setup@1.0.0 start C:\dev\github\nodejs_typescript_setup
> node dist/app.js

Server running...
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