Building a RESTful CRUD API with Node.js, Express, MongoDB

Used Libraries

Express
Validator
Mongoose

_____________Just 3 Steps________________

Step 1

Initialize the project

npm init -y
npm install --save-dev nodemon
npm install express mongoose
npm install validator

Now go to the package.json and modifiy the scripts property like this.

Then create folder call utils and create a file call db.js inside it. Here is my project structure.

If  you haven't any idea to get MongoDB Connection String please refer first part from here.
Follow these set of code for RESTful API crud operations.

   Step 2

   db.js

const mongoose = require('mongoose');
const validator = require('validator');

const url = 'MongoDB Connection String';



mongoose.connect(url,{useUnifiedTopology:true,useNewUrlParser:true});

const Schema = mongoose.Schema;

const userSchema = new Schema({
    name : {
        type : String,
        require : true,
        trim : true
    },
    age : {
        type : Number,
        require : true,
        validate(value){
            if(value < 0){
                throw new Error('please enter valid age');
            }
        }
    },
    email : {
        type : String,
        require : true,
        validate(value){
            if(!validator.isEmail(value)){
                throw new Error('please enter valid email');
            }
        }
    },
    password : {
        type : String,
        require : true,
        minlength : 5
    }
});

const user = mongoose.model('User',userSchema);
module.exports = user;

   Step 3

   app.js

const express = require('express');
require('./utils/db');
const User = require('./utils/db');

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

app.listen(3000);

//create user
app.post('/users',async(req,res)=>{ 
    const user1 = new User(req.body);
    try{
        await user1.save(); 
        res.status(201).send(user1);
    }
    catch(e){
        res.status(400).send(e.message);
    }
});

//fetch users
app.get('/users',async(req,res)=>{ 
    try{
        const users = await User.find({}); 
        if(!users){
            return res.status(404).send();
        }
        else{
            res.status(200).send(users);
        }
    }
    catch(e){
        res.status(400).send(e.message);
    }
});

//fetch user by id
app.get('/users/:id',async(req,res)=>{ 
    try{
        console.log(req.params);
        const user = await User.findById(req.params.id);

        if(!user){
            return res.status(404).send();
        }
        else{
            res.status(500).send(user);
        }
    }
    catch(e){
        res.status(400).send(e.message);
    }
});

//update user
app.patch('/users/:id',async(req,res)=>{ 
    try{
        console.log(req.params);
        const user = await User.findByIdAndUpdate(req.params.id,req.body,{new:true,runValidators:true});

        if(!user){
            return res.status(404).send();
        }
        else{
            res.status(200).send(user);
        }
    }
    catch(e){
        res.status(400).send(e.message);
    }
});


//delete user
app.delete('/users/:id',async(req,res)=>{ 
    try{
        console.log(req.params);
        const user = await User.findByIdAndDelete(req.params.id);

        if(!user){
            return res.status(404).send();
        }
        else{
            res.status(200).send(user);
        }
    }
    catch(e){
        res.status(400).send(e.message);
    }
});

Now you can run the project from npm run dev. okay cool.

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