Node.js rest API using express

Init the project inside your project folder

npm init

Install express package from npm.

npm i express

Minimal code to serve 'hello world'

//server.js

const express = require('express');
const app = express();
const port = 3000;

app.get('/', (req, res) => {
  res.send('Hello World!');
})

app.listen(port, () => {
  console.log(`App listening on port ${port}`);
})

now run the server using node

node server.js

let test it using curl command or a browser.

curl http://localhost:3000/

the result should be 'Hello World'.

We have seen how to create our first server using express, now we will add some route to: get, post, update and delete data.

//server.js

const express = require('express');
const app = express();
const port = 3000;

app.get('/', (req, res) => {
  res.send('Hello World!');
})

let users = [{
  id: 0,
  name: 'user1',
  age: 28
}, {
  id: 1,
  name: 'user2',
  age: 29
}, {
  id: 2,
  name: 'user3',
  age: 30
}
]

app.get('/users', (req, res) => {
  res.status(200).json({
    status: 'success',
    data: users
  });
})

app.post('/users', (req, res) => {
  const user = req.body;
  users.push(user);

  res.status(201).json({
    status: 'success',
    data: users,
  });
})

app.put('/users/:id', (req, res) => {
  const userId = req.params.id;
  const newUser = req.params.body;

  users = users.map((user) => {
    if (user.id == userId) {
      user.name = newUser.name;
      user.age = newUser.age;
    }
    return user;
  });

  res.status(201).json({
    status: 'success',
    data: users,
  });
});

app.delete('/users/:id', (req, res) => {
  const userId = req.params.id;

  users = users.map((user) => {
    if (user.id != userId) {
      return user;
    }
  });

  res.status(204).json({
    status: 'success',
    data: null,
  });
});

app.listen(port, () => {
  console.log(`App listening on port ${port}`);
})

Next steps:

• Use Middlewares;
• Structure the project code;
• Use Mongodb as a database;
• Secure the api;
• Write tests;
• Migrate to micro-service architechture;