1. Install Mongoose
First, you need to install Mongoose in your project. You can do this by running the following command in your terminal:
npm install mongoose
2. Connect to MongoDB
Once you have installed Mongoose, you can connect to your MongoDB database by creating a Mongoose connection. To do this, you need to create a new Mongoose instance and pass in the connection string for your MongoDB database.
const mongoose = require(‘mongoose’);
mongoose.connect(‘mongodb://localhost/my_database’, {
useNewUrlParser: true,
useUnifiedTopology: true
});
3. Create a Schema
Once you have connected to your MongoDB database, you need to create a Mongoose Schema. A Schema is a blueprint for your data that defines the shape of the documents in your collection.
const userSchema = new mongoose.Schema({
name: String,
age: Number
});
4. Create a Model
Once you have created a Schema, you can use it to create a Mongoose Model. A Model is a class that allows you to create documents in your collection.
const User = mongoose.model(‘User’, userSchema);
5. Create a Document
Once you have created a Model, you can use it to create documents in your collection.
const user = new User({
name: ‘John Doe’,
age: 25
});
user.save();
6. Query the Database
Once you have created documents in your collection, you can query the database to retrieve them.
User.find({name: ‘John Doe’}, (err, users) => {
if (err) {
console.log(err);
} else {
console.log(users);
}
});
Connect to mongodb using mongoose in node js express tutorial, you will learn how to connect mongoose with node js express application.
MongoDB is a document database built on a scale-out architecture that has become popular with developers of all kinds who are building scalable applications using agile methodologies. MongoDB was built for people who are building internet and business applications who need to evolve quickly and scale elegantly.
How to Connect Mongoose with Node js Express Application
- Step 1 – Create Node JS App
- Step 2 – Install Express-Validator and Body Parser Module
- Step 3 – Create Server.js File
- Step 4 – Connect App to MongoDB
- Step 5 – Start App Server
Step 1 – Create Node JS App
Create Node js express app; So, execute the following command on terminal:
mkdir my-app cd my-app npm init -yes
Step 2 – Install Mongoose and Body Parser Module
Install mongoose s and body-parser modules into your node js express application by executing the following command on command prompt:
npm install mongoose express body-parser
- body-parser – Node.js request body parsing middleware which parses the incoming request body before your handlers, and make it available under req.body property. In other words, it simplifies the incoming request.
Step 3 – Create Server.js File
Create Server.js and import above installed modules in it. So visit your app root directory and create Server.js and validate fields; as following:
const express = require("express")
const mongoose = require("mongoose")
const bodyParser = require("body-parser")
const app = express()
const PORT = 3000
app.listen(PORT, () => {
console.log(`app is listening to PORT ${PORT}`)
})
Step 4 – Connect App to MongoDB
Connect mongoose to local MongoDB instance with db name as testdb; so add the following code into server.js file:
mongoose.connect("mongodb://localhost:27017/testdb", {
useNewUrlParser: "true",
})
mongoose.connection.on("error", err => {
console.log("err", err)
})
mongoose.connection.on("connected", (err, res) => {
console.log("mongoose is connected")
})
Step 5 – Start App Server
Open your command prompt and execute the following command to run node js express file upload application:
//run the below command node sever.js
Conclusion
Connect to mongodb using mongoose in node js express tutorial, you have learn how to connect mongodb using mongoose with node js express application.