M Stack Tutorial Part 12 - MongoDB Models with Mongoose

Overview

• This session focuses on creating a simple model in Express.js using Mongoose.
• Previous session recap: Created a controller and migrated API logic from route.js to a controller file.

Key Concepts

What is a Schema?

• Defines the structure of documents in a collection.
• Specifies fields, data types, validation, etc.
• Schema was previously created using MongoDB Cluster.

What is a Model?

• A compiled version of a schema.
• Responsible for creating and reading documents from the MongoDB database.

Steps to Create a MongoDB Model with Mongoose

1. Install Mongoose Package
   • Use command: npm install mongoose
2. Connect to MongoDB
   • Set up a connection (to be done later in the session).
3. Define a Schema
   • Represent the structure of documents.
4. Compile Schema into a Model
   • Use the defined schema in the application.

Coding Steps

1. Create Models Folder

   • In Visual Studio, create a folder named models.

2. Create user.js Model

   • File represents the users collection.
   • Define schema with properties: email, first name, last name.
   • Set property type as String.

3. Wrap Schema in Schema Object

   • Import Mongoose with: const mongoose = require('mongoose');
   • Define schema: const Schema = mongoose.Schema;
   • Create User Schema: const userSchema = new Schema({...});

4. Add Properties

   • Example: Make email property required: email: { type: String, required: true }.

5. Export User Schema

   • Create model: const User = mongoose.model('User', userSchema);
   • Export: module.exports = User;

Tools for Schema Generation

• Transformation tools available to convert JSON to Mongoose schema.
• Copy the existing user collection in JSON format and paste it into the tool.
• The output schema can be copied into the Visual Studio solution.

Next Session

• Focus on connecting the Mongoose model and updating the database using model files.