Rest APIs CRUD

CRUD with REST: overview

Each CRUD operation aligns with specific HTTP methods:

• Create: Use POST to add new resources.
• Read: Use GET to retrieve existing resources.
• Update: Use PUT or PATCH to modify resources.
• Delete: Use DELETE to remove resources.

Building a REST API Using Node.js and Express

To create a REST API for the above CRUD operations, use Node.js with the Express framework.

Install dependencies:

bash

npm install express body-parser

Example code

const express = require('express');
const bodyParser = require('body-parser');

const app = express();
app.use(bodyParser.json());

let customers = [];

// Create
app.post('/api/customers', (req, res) => {
  const customer = req.body;
  customers.push(customer);
  res.status(201).json(customer);
});

// Read
app.get('/api/customers', (req, res) => {
  res.json(customers);
});

// Update
app.put('/api/customers/:id', (req, res) => {
  const id = parseInt(req.params.id);
  const updatedCustomer = req.body;
  customers[id] = updatedCustomer;
  res.json(updatedCustomer);
});

// Delete
app.delete('/api/customers/:id', (req, res) => {
  const id = parseInt(req.params.id);
  customers.splice(id, 1);
  res.status(204).send();
});

// Start Server
app.listen(3000, () => {
  console.log('Server running on http://localhost:3000');
});

Consuming CRUD API

Below are examples for each operation using REST APIs with multiple technologies.

1. Create (POST)

The POST method is used to create a new resource on the server by sending data in the request body.

Endpoint

POST /api/customers

Example payload

{
  "name": "John Doe",
  "email": "john.doe@example.com",
  "active": true
}

Examples by technology:

JavaScript (Axios)

const axios = require('axios');
axios.post('https://example.com/api/customers', {
  name: 'John Doe',
  email: 'john.doe@example.com',
  active: true
})
  .then(response => console.log('Created:', response.data))
  .catch(error => console.error(error));

Python (Requests)

import requests

url = 'https://example.com/api/customers'
data = {
    'name': 'John Doe',
    'email': 'john.doe@example.com',
    'active': True
}

response = requests.post(url, json=data)
print('Created:', response.json())

2. Read (GET)

The GET method retrieves data from the server, typically fetching one or more resources.

Endpoint

GET /api/customers

Examples by technology:

JavaScript (Axios)

axios.get('https://example.com/api/customers')
  .then(response => console.log('Data:', response.data))
  .catch(error => console.error(error));

Python (Requests)

response = requests.get('https://example.com/api/customers')
print('Data:', response.json())

3. Update (PUT)

The PUT method updates an existing resource by sending the modified data in the request body. Use PATCH for partial updates.

Endpoint

PUT /api/customers/1

Example payload

{
  "name": "John Updated",
  "email": "john.updated@example.com",
  "active": false
}

Examples by technology:

JavaScript (Axios)

axios.put('https://example.com/api/customers/1', {
  name: 'John Updated',
  email: 'john.updated@example.com',
  active: false
})
  .then(response => console.log('Updated:', response.data))
  .catch(error => console.error(error));

Python (Requests)

response = requests.put(
    'https://example.com/api/customers/1',
    json={
        'name': 'John Updated',
        'email': 'john.updated@example.com',
        'active': False
    }
)
print('Updated:', response.json())

4. Delete (DELETE)

The DELETE method removes a resource from the server, typically identified by its unique ID.

Endpoint

DELETE /api/customers/1

Examples by technology:

JavaScript (Axios)

axios.delete('https://example.com/api/customers/1')
  .then(response => console.log('Deleted:', response.data))
  .catch(error => console.error(error));

Python (Requests)

response = requests.delete('https://example.com/api/customers/1')
print('Deleted:', response.status_code)

Notable libraries and example projects

1. NestJSX CRUD - Framework on top of NestJS for building CRUD Apps
2. Django Ninja CRUD - built-in CRUD for Django Ninja Projects
3. PHP CRUD API - Single file CRUD API on top of SQL database