Create RESTful api in Node js – Today we will learn how to create node js apis using node js framework express with mysql database.
If you want to create a RESTful API with Node Js framework Express js? Here is the rest api crud tutorial, by reading this tutorial you can create our own REST API application server.
We are going to use a very popular web node js framework called Express to create RESTful APIs using mysql database.
Use the below command and create your express project with name expressfirst
mkdir node-rest-crud-api
cd node-rest-crud-api
After successfully created node-rest-crud-api folder in your system. Next follow the below commands and install node js express in your project :
npm init --yes
npm install
Now install express js framework and MySQL driver with NPM. go to terminal and use the below commands :
npm install express --save
npm install mysql --save
npm install body-parser --save
Next we need to create database and table for perform crud operation of node js restful api.
-- Table structure for users
CREATE TABLE IF NOT EXISTS users (
id int(11) NOT NULL,
name varchar(200) NOT NULL,
email varchar(200) NOT NULL,
created_at datetime NOT NULL DEFAULT CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
ALTER TABLE users ADD PRIMARY KEY (id);
ALTER TABLE users MODIFY id int(11) NOT NULL AUTO_INCREMENT;
INSERT INTO users (id, name, email, created_at) VALUES
(1, 'Test', 'test@g.co', '2019-02-28 13:20:20'),
(2, 'john', 'john@g.co', '2019-02-28 13:20:20'),
(3, 'tutsmake', 'tuts@g.co', '2019-02-28 13:20:20'),
(4, 'tut', 'tut@g.co', '2019-02-28 13:20:20'),
(5, 'mhd', 'mhd@g.co', '2019-02-28 13:20:20');
Next we need to create server.js file inside of node-rest-crud-api folder and put the connection. server.js is entry point.
var express = require('express');
var app = express();
var bodyParser = require('body-parser');
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({
extended: true
}));
// default route
app.get('/', function (req, res) {
return res.send({ error: true, message: 'hello' })
});
// set port
app.listen(3000, function () {
console.log('Node app is running on port 3000');
});
module.exports = app;
We need to required database connection for fetching or update data into database :
// connection configurations
var dbConn = mysql.createConnection({
host: 'localhost',
user: 'root',
password: '',
database: 'node_js_api'
});
// connect to database
dbConn.connect();
| Method | Url | Action |
| GET | /users | fetch all users |
| GET
| user/1 | fetch user with id ==1 |
| POST | user | add new user |
| PUT | user | update user by id == 1 |
| DELETE | user | delete user by id == 1 |
Now we will first implement route of users list api with we will Fetch all users into database.
// Retrieve all users
app.get('/users', function (req, res) {
dbConn.query('SELECT * FROM users', function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results, message: 'users list.' });
});
});
This function simply return all users information as you can see in this query, to call this API use this URL http://127.0.0.1:3000/users.
Now we will implement single user api. This api will return single user record.
// Retrieve user with id
app.get('/user/:id', function (req, res) {
let user_id = req.params.id;
if (!user_id) {
return res.status(400).send({ error: true, message: 'Please provide user_id' });
}
dbConn.query('SELECT * FROM users where id=?', user_id, function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results[0], message: 'users list.' });
});
});
Call this API use this URL http://127.0.0.1/user/1.
Now We will implement add new user route so that when a user sends a post request with required data, app will add a new record to the database.
// Add a new user
app.post('/user', function (req, res) {
let user = req.body.user;
if (!user) {
return res.status(400).send({ error:true, message: 'Please provide user' });
}
dbConn.query("INSERT INTO users SET ? ", { user: user }, function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results, message: 'New user has been created successfully.' });
});
});
This API function accepts post request and insert record in your database. To call this API use this URL http://127.0.0.1:3000/add
Now We will implement update user route so that when a user sends a post request with required data, app will update record to the database.
// Update user with id
app.put('/user', function (req, res) {
let user_id = req.body.user_id;
let user = req.body.user;
if (!user_id || !user) {
return res.status(400).send({ error: user, message: 'Please provide user and user_id' });
}
dbConn.query("UPDATE users SET user = ? WHERE id = ?", [user, user_id], function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results, message: 'user has been updated successfully.' });
});
});
This API accept put request and updates record in your database. To call this API use this URL http://127.0.0.1/user/{id}
We are going to create a new route so that when a user sends a delete request, the app will delete a record from the database.
// Delete user
app.delete('/user', function (req, res) {
let user_id = req.body.user_id;
if (!user_id) {
return res.status(400).send({ error: true, message: 'Please provide user_id' });
}
dbConn.query('DELETE FROM users WHERE id = ?', [user_id], function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results, message: 'User has been updated successfully.' });
});
});
server.js
file.var express = require('express');
var app = express();
var bodyParser = require('body-parser');
var mysql = require('mysql');
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({
extended: true
}));
// default route
app.get('/', function (req, res) {
return res.send({ error: true, message: 'hello' })
});
// connection configurations
var dbConn = mysql.createConnection({
host: 'localhost',
user: 'root',
password: '',
database: 'node_js_api'
});
// connect to database
dbConn.connect();
// Retrieve all users
app.get('/users', function (req, res) {
dbConn.query('SELECT * FROM users', function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results, message: 'users list.' });
});
});
// Retrieve user with id
app.get('/user/:id', function (req, res) {
let user_id = req.params.id;
if (!user_id) {
return res.status(400).send({ error: true, message: 'Please provide user_id' });
}
dbConn.query('SELECT * FROM users where id=?', user_id, function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results[0], message: 'users list.' });
});
});
// Add a new user
app.post('/user', function (req, res) {
let user = req.body.user;
if (!user) {
return res.status(400).send({ error:true, message: 'Please provide user' });
}
dbConn.query("INSERT INTO users SET ? ", { user: user }, function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results, message: 'New user has been created successfully.' });
});
});
// Update user with id
app.put('/user', function (req, res) {
let user_id = req.body.user_id;
let user = req.body.user;
if (!user_id || !user) {
return res.status(400).send({ error: user, message: 'Please provide user and user_id' });
}
dbConn.query("UPDATE users SET user = ? WHERE id = ?", [user, user_id], function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results, message: 'user has been updated successfully.' });
});
});
// Delete user
app.delete('/user', function (req, res) {
let user_id = req.body.user_id;
if (!user_id) {
return res.status(400).send({ error: true, message: 'Please provide user_id' });
}
dbConn.query('DELETE FROM users WHERE id = ?', [user_id], function (error, results, fields) {
if (error) throw error;
return res.send({ error: false, data: results, message: 'User has been updated successfully.' });
});
});
// set port
app.listen(3000, function () {
console.log('Node app is running on port 3000');
});
module.exports = app;
We have successfully implemented node js crud api using express js.
#nodejs #javascript #MySQL #Express