How to Create REST API with Node, Express, and Mongoose

Node.js, Express.js, Mongoose.js and MongoDB are the great tools for building easy and fast REST API.
Node.js is a packaged compilation of Googleâ€™s V8 JavaScript engine.
Express.js is javascript web server that has complete function of web development including REST API.

Before we begin, are mandatory to be installed on your device

Node.js
MongoDB
Editor or IDE

Here we are using Terminal and Atom as the text editor. For Windows user, you can work using Node.js command line.

Create Express.js Project and Install Required Modules

Lunch your terminal or node command line, go to your projects folder.

Then, using this command install express generator.

$ sudo npm install express-generator -g

Create an Express.js app using this command.

$ express node-rest-api -e

Next, go to newly created project folder then install node modules.

$ cd node-rest-api && npm install

Run the server using the line below.

$ npm start

You will get this log in the terminal.

> node-rest-api@0.0.0 start /Users/didin/Documents/NodeApps/node-rest-api
> node ./bin/www

Go to your browser and type localhost:3000, Your server is ready if you get the result below

Add Mongoose.js Module as ORM for MongoDB

Presse CTRL+C to Stop node then type the command to install Mongoose.js module.

$ npm install mongoose --save

then type this command to start MongoDB server.

$ mongod

Now, using an IDE or a text editor, open and edit app.js in the root of project folder.
Declare mongoose in require sections.

var mongoose = require('mongoose');

Use mongoose with native Node Promise.

mongoose.Promise = global.Promise;

Then, Create a connection to MongoDB.

mongoose.connect('mongodb://localhost/product')
   .then(() =>  console.log('connection successful'))
   .catch((err) => console.error(err));

Run the node app using this

$ npm start

if you get this message on your terminal, the connection to MongoDB is successful.

> node-rest-api@0.0.0 start /Users/didin/Documents/NodeApps/node-rest-api
> node ./bin/www
connection successful

Create Product Mongoose Model

CTRL+C in the terminal to stop node server, then create models directory and javascript file as the model.

$ mkdir models
$ touch models/Product.js

In Product.js file the add the following lines of codes.

var mongoose = require('mongoose');
var ProductSchema = new mongoose.Schema({
 prod_name: String,
 prod_desc: String,
 prod_price: Number,
 updated_at: { type: Date, default: Date.now },
});
module.exports = mongoose.model('Product', ProductSchema);

Create Routes for REST API endpoint

we will build the following functions for Our REST API .

Method	Endpoints	Notes
GET	/product	Get all products
GET	/product/:id	Get single product
POST	/product	Add product
PUT	/product/:id	Update product
DELETE	/product/:id	Delete product

First, add the javascript file to routes folder.

$ touch routes/products.js

in routes/products.js add this lines of codes.

var express = require('express');
var router = express.Router();
var mongoose = require('mongoose');
var Product = require('../models/Product.js');

/* GET ALL PRODUCTS */
router.get('/', function(req, res, next) {
 Product.find(function (err, products) {
   if (err) return next(err);
   res.json(products);
 });
});

/* GET SINGLE PRODUCT BY ID */
router.get('/:id', function(req, res, next) {
 Product.findById(req.params.id, function (err, post) {
   if (err) return next(err);
   res.json(post);
 });
});

/* SAVE PRODUCT */
router.post('/', function(req, res, next) {
 Product.create(req.body, function (err, post) {
   if (err) return next(err);
   res.json(post);
 });
});

/* UPDATE PRODUCT */
router.put('/:id', function(req, res, next) {
 Product.findByIdAndUpdate(req.params.id, req.body, function (err, post) {
   if (err) return next(err);
   res.json(post);
 });
});

/* DELETE PRODUCT */
router.delete('/:id', function(req, res, next) {
 Product.findByIdAndRemove(req.params.id, req.body, function (err, post) {
   if (err) return next(err);
   res.json(post);
 });
});

module.exports = router;

Next, In app.js add product route as require after users require.

var products = require('./routes/products');

Then add use after use of users.

app.use('/products', products);

Test REST API Endpoints

There are so many tools for testing REST API, we are testing using CURL from the terminal.

We start with Add/Save product data first.

$ curl -i -X POST -H "Content-Type: application/json" -d '{ "prod_name":"HP laptop ","prod_desc":"the new hp","prod_price": 999 }' localhost:3000/products

If you get this response l then the product is saved successfully.

HTTP/1.1 200 OK
X-Powered-By: Express
Content-Type: application/json; charset=utf-8
Content-Length: 185
ETag: W/"b9-ymiFjoNdt5wABoii1CiYbg"
Date: Sun, 19 Feb 2024 03:30:35 GMT
Connection: keep-alive

{"__v":0,"prod_name":"HP laptop ","prod_desc":"the new hp ","prod_price":999 ,"_id":"1","updated_at":"2018-08-07T03:30:34.415Z"}

You can the same to save more records.

Now, we are going to get all products data by typing this command.

$ curl -i -H "Accept: application/json" localhost:3000/products

The response will be displayed in JSON format like the following.

HTTP/1.1 200 OK
X-Powered-By: Express
Content-Type: application/json; charset=utf-8
Content-Length: 344
ETag: W/"158-V1WRYZrNC8yW7HFEfOSSew"
Date: Sun, 19 Feb 2024 03:34:26 GMT
Connection: keep-alive
[{"_id":"1","prod_name":"HP laptop","prod_desc":"the new hp ","prod_price":999,"__v":0,"updated_at":"2018-08-07T03:30:34.415Z"},{"_id":"2","prod_name":"Sony Xperia","prod_desc":" Sony phone"," prod_price":600,"__v":0,"updated_at":"2018-08-05T03:33:24.941Z"}]

Next, to get one product by id use this command.

$ curl -i -H "Accept: application/json" localhost:3000/products/2

Here is the response.

HTTP/1.1 200 OK
X-Powered-By: Express
Content-Type: application/json; charset=utf-8
Content-Length: 156
ETag: W/"9c-NYW3p4BkPVbiNf05Ezj+zA"
Date: Sun, 19 Feb 2024 03:45:48 GMT
Connection: keep-alive

{"_id":"2","prod_name":"Sony Xperia","prod_desc":"Sony phone  ","prod_price":600,"__v":0,"updated_at":"2018-08-05T03:33:24.941Z"}]

Next, we are going to update a product by id using this command.

$ curl -i -X PUT -H "Content-Type: application/json" -d '{"prod_desc":"the old hp"}' localhost:3000/products/1

the response should be like this.

HTTP/1.1 200 OK
X-Powered-By: Express
Content-Type: application/json; charset=utf-8
Content-Length: 185
ETag: W/"b9-k9Wipgusc9JVZAMyHgjVXw"
Date: Sun, 19 Feb 2024 03:38:24 GMT
Connection: keep-alive

{"_id":"1","prod_name":"HP laptop","prod_desc":"the new hp ","prod_price":999,"__v":0,"updated_at":"2018-08-07T06:30:34.415Z"}

Finally, we are going to delete a product by id like the following.

$ curl -i -X DELETE localhost:3000/products/1

The response will look like this.

HTTP/1.1 200 OK
X-Powered-By: Express
Content-Type: application/json; charset=utf-8
Content-Length: 155
ETag: W/"9b-pP1KXaQhyqcMkvBlLa6pFQ"
Date: Sun, 19 Feb 2024 03:41:54 GMT
Connection: keep-alive

{"_id":"1","prod_name":"HP laptop","prod_desc":"the new hp ","prod_price":999,"__v":0,"updated_at":"2018-08-07T06:30:34.415Z"}

Quick REST API Creation using Node-Restful Library

One of quicker and elegant method for creating REST API is the Node-Restful library that you can find on Github. You can add the library using npm command.

$ npm install node-restful --save

In app.js on the root of the project. Add require line for Node-Restful and Method-Override.

var restful = require('node-restful');
var methodOverride = require('method-override');

Change â€œbodyParse extendedâ€ value to true then add this lines.

app.use(bodyParser.urlencoded({'extended':'true'}));
app.use(bodyParser.json({type:'application/vnd.api+json'}));
app.use(methodOverride());

We will create mongoose model that can ve use together with Node-Restful library. Here we are creating â€œcategoryâ€ model.

var Category = app.resource = restful.model('category', mongoose.Schema({
 cat_name: String,
}))
.methods(['get', 'post', 'put', 'delete']);
Category.register(app, '/category');

Run again the app and test it using previous way for testing REST API.