Building a Todo List API with a Database

To demonstrate the concepts discussed, let’s create a simple API using Node.js and MongoDB. We’ll create an endpoint /todos that retrieves a list of todos from a MongoDB database.

First, we need to set up our Node.js project and install the necessary dependencies:

mkdir todo-api
cd todo-api
npm init -y
npm install express mongoose

Explanation:

• mkdir todo-api: This creates a new directory named todo-api where our project will be located.
• cd todo-api: This changes the current directory to todo-api so we can work inside it.
• npm init -y: This initializes a new Node.js project in the todo-api directory with default settings, creating a package.json file.
• npm install express mongoose: This installs the express framework and mongoose library as project dependencies. Express is used for handling HTTP requests and routes, while Mongoose simplifies interaction with MongoDB, our database choice for this project.

Next, let’s create our index.js file:

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

// Connect to MongoDB
mongoose.connect('mongodb://localhost:27017/todos', {
  useNewUrlParser: true,
  useUnifiedTopology: true,
});

// Create a schema for our todo collection
const todoSchema = new mongoose.Schema({
  title: String,
  completed: Boolean,
});

// Create a model based on the schema
const Todo = mongoose.model('Todo', todoSchema);

// Create an Express app
const app = express();

// Define a route to fetch all todos
app.get('/todos', async (req, res) => {
  try {
    // Retrieve all todos from the database
    const todos = await Todo.find();
    res.json(todos); // Send the todos as a JSON response
  } catch (err) {
    res.status(500).json({ error: 'Internal Server Error' }); // Handle any errors
  }
});

// Start the server
const PORT = 3000;
app.listen(PORT, () => {
  console.log(`Server is running on port ${PORT}`);
});

Explanation:

• It requires the express and mongoose modules for handling HTTP requests and interacting with MongoDB, respectively.
• It connects to a MongoDB database named todos running on the default port 27017.
• It defines a schema for the todo collection with title (String) and completed (Boolean) fields.
• It creates a model Todo based on the schema, allowing us to perform CRUD operations on the todo collection.
• It creates an Express app and defines a GET route /todos to fetch all todos from the database and return them as a JSON response.
• It starts the server on port 3000 and logs a message to the console indicating that the server is running.

APIs define methods and protocols for accessing and exchanging data, allowing developers to integrate various services and functionalities into their applications seamlessly. On the other hand, databases store data in a structured manner, enabling efficient storage, retrieval, and management of information.

Together, APIs and databases form the backbone of modern software systems, facilitating communication and data management.

Understanding how APIs work with databases is crucial for developers building robust and scalable applications. In this article, We will learn about How Does an API Work with A Database by Understanding APIs and Databases along with an Example of Building a Todo List API with a Database and so on