Updating Records by ID with Mongoose

In this lesson, we'll learn how to update records in a MongoDB collection using Mongoose. Updating records is essential for maintaining accurate and useful data in an application.

You'll learn

• how to set up a MongoDB connection using Mongoose,
• create a schema and model for a MongoDB collection,
• update a document by its ID,
• handle potential errors during the update process.

Let's start by setting up a connection to MongoDB using Mongoose. This is important because it establishes a link between our application and the database, allowing us to perform operations like updates.

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

const app = express();
const PORT = 3000;

// Set mongoose strictQuery to true to suppress deprecation warning
mongoose.set('strictQuery', true);

// Connect to MongoDB
mongoose.connect('mongodb://127.0.0.1:27017/todo-app', {
    useNewUrlParser: true,
    useUnifiedTopology: true
}).then(() => {
    console.log('Connected to MongoDB');
}).catch((error) => {
    console.error('Connection error', error);
});

app.use(express.json());

In this code, we start by importing express and mongoose. We then set up an Express application and define the port number. Next, we configure mongoose to suppress a deprecation warning with mongoose.set('strictQuery', true). We connect to the MongoDB database using mongoose.connect, providing the connection string and options. A successful connection logs "Connected to MongoDB" to the console, while an error logs the connection error. Finally, we use app.use(express.json()) to enable JSON parsing of request bodies.

Now we'll define a schema and model for our "ToDo" items in the database. This is helpful for structuring data and interacting with it in a consistent manner.

// Define a schema and model for ToDo items
const todoSchema = new mongoose.Schema({
    task: { type: String, required: true },
    completed: { type: Boolean, default: false }
});

const Todo = mongoose.model('Todo', todoSchema);

In this code, we define todoSchema to specify the structure of a "ToDo" item, with fields task and completed. The task field is a required string, and the completed field is a boolean that defaults to false. We then create the Todo model from this schema, which allows us to interact with the "ToDo" collection in the database.