Setting up a Node.js Express project with Typescript

Setting up a Node.js project with TypeScript can significantly improve your developer experience by providing static type checking in your code. In this blog, I’ll guide you through the steps to set up a Node.js Express project with TypeScript.

Create your project directory

Create a directory for your project and then navigate to it. In this example the name of our directory is node-ts.

mkdir node-ts
cd node-ts

Initialize the project

Install a new node project with npm init. This will create a package.json file in the root of your project.

npm init

Install TypeScript

Install TypeScript as a development dependancy.

npm install --save-dev typescript

Initialize the TypeScript configuration file

npx tsc --init

Set up your project structure

Create directories for your source (src) and compiled files (dist).

mkdir src
mkdir dist

Install development tools

Install nodemon and ts-node as development dependencies to run and monitor your project.

npm install nodemon ts-node --save-dev

Configure scripts

Configure a script in the package.json to run your server in development mode.

"scripts": {
    "dev": "nodemon --exec ts-node src/server.ts"
  }

Configure nodemon

Create a nodemon.json file to configure nodemon to watch the TypeScript files.

{
  "watch": ["src"],
  "ext": "ts,json",
  "exec": "ts-node ./src/server.ts"
}

Configure TypeScript

In the tsconfig.json, specify the compiler options and include your source files.

{
  "compilerOptions": {
    "target": "es2016",
    "module": "commonjs",
    "rootDir": "./src",
    "outDir": "./dist",
    "esModuleInterop": true,
    "forceConsistentCasingInFileNames": true,
    "strict": true,
    "skipLibCheck": true
  },
  "include": ["src/**/*.ts"]
}

Install Express

npm install express
npm install @types/express --save-dev

Create a simple express server

Create a server.ts file in your src/ directory with the following basic set up for an express server.

import express from 'express';

const app = express();
const port = process.env.PORT || 3000;

app.get("https://dev.to/", (req, res) => {
  res.send('Hello, TypeScript with Node.js and Express!');
});

app.listen(port, () => {
  console.log(`Server is running at http://localhost:${port}`);
});

Start the development server

To start the server run the script you configured in your package.json file.

npm run dev

Your Node.js Express with TypeScript project should be up and running now.