ExpressJs is a minimal and flexible Node.js web application framework that is minimal, lightweight and easy to use. Express has made it easy to write backend and build REST API's code in JavaScript.

If you are lazy like me, you can directly download my script from here

Or

Run the following code

wget -O express.sh https://raw.githubusercontent.com/Arghyahub/SCRIPTS/main/express/express.sh
chmod +x express.sh
./express.sh

Or

Continue Installation

Make sure you have nodejs installed.

Follow the steps

npm init
npm install express cors dotenv
mkdir src
touch src/app.js

This is how you can run the server

import express from "express";
import cors from "cors";
import dotenv from "dotenv";
 
dotenv.config();
const app = express();
const PORT = process.env.PORT || 5000;
 
app.use(cors());
app.use(express.json());
 
app.get("/", (req, res) => {
  res.send("Hello from Arghya!");
});
 
app.listen(PORT, () => {
  console.log("Server is running on port", PORT);
});

Now copy the following code in your package.json file

"scripts": {
    "build": "npm i",
    "dev": "nodemon --watch src src/app.js",
    "start": "node ./src/app.js"
},

Now run npm run dev to start the server in dev mode.

TypeScript

If you are using TypeScript, you can follow the steps below

npm init
npm install express cors dotenv
npm install -D typescript ts-node-dev @types/express @types/cors
mkdir src
touch src/app.ts

Now setup your tsconfig.json file

{
  "compilerOptions": {
    "target": "ES2020",
    "module": "NodeNext",
    "rootDir": "./src",
    "moduleResolution": "NodeNext",
    "outDir": "./dist",
    "esModuleInterop": true,
    "forceConsistentCasingInFileNames": true,
    "strict": false,
    "skipLibCheck": true
  },
  "include": ["./src/**/*"]
}

Now write the app code

import express from "express";
import cors from "cors";
import dotenv from "dotenv";
 
dotenv.config();
const app = express();
const PORT = process.env.PORT || 5000;
 
app.use(cors());
app.use(express.json());
 
app.get("/", (req, res) => {
  res.send("Hello from Arghya!");
});
 
app.listen(PORT, () => {
  console.log("Server is running on port", PORT);
});

copy the scripts to your package.json

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

Now run npm run dev to start the server in dev mode.

Configuring ORMS

An ORM(Object Relational Mapping) is a programming technique for converting data between incompatible type systems in object-oriented programming languages.

But I don't want to write Object oriented code in JavaScript. I prefer to write SQL queries.

But listen me out, ORMs are not that bad. They can save you a lot of time and effort.

2 of my favorite ORMS are Mongoose for MongoDB and Prisma for SQL based databases. [ Honorable Mention: Sequelize ]

Mongoose

Mongoose is pretty easy to use and MongoDB's best part is its mostly free and easy to work with.

Just run

npm install mongoose

Prisma

Prisma's models, relation patterns and queries are very easy to use and understand.

Just run

npm install prisma
npx prisma init
npm install @prisma/client

Conclusion

You are mostly done with setting up express. I used to think backend is just writing routes fetching data from database and sending it to the client. But it's more than that. You have to think about security, performance, scalability and a lot more.

After joining a company, I have worked more on designing databases, integrating with third party services(with poor documentation), dockerizing the app. I have learned a lot and I am still learning.

Thank you for reading this article. I hope it helps 🙏.