¿Que es una API Restful?

The creation of RESTful APIs is a fundamental component of modern web development, enabling efficient communication between the frontend and backend of our applications. Express.js has become an essential tool for developers looking to implement these interfaces quickly and effectively. Mastering these concepts will open doors in the world of web development and allow you to build more robust and scalable applications.

What is a RESTful API and why is it important?

A RESTful API (Representational State Transfer) is a set of principles that facilitates communication with web services. This architectural approach allows us to leverage HTTP protocols using different verbs that define specific interactions with information.

In modern web development, it is common to separate the logic into two main elements:

• Backend: Where the RESTful API plays a fundamental role.
• Frontend: Which consumes and interacts with this API.

This separation allows for a more organized and scalable development, where each part can evolve independently while maintaining a clear communication interface.

HTTP verbs in a RESTful API

The most common HTTP methods you will encounter when working with RESTful APIs are:

• GET: Used to request a specific resource from the server. For example, to obtain information about a product, user or any other data.
• POST: Used to send data to the server to be processed or stored. Ideal for creating new records or sending authentication credentials.
• PUT: Used to update or completely replace an existing resource on the server.
• PATCH: Used to perform partial updates of a resource. Unlike PUT, it only modifies the specified fields.
• DELETE: As its name indicates, it deletes an existing resource from the server.

These verbs make up what is known as CRUD (Create, Read, Update, Delete), which are the fundamental operations for data manipulation in any system.

How to implement a complete CRUD with Express.js?

To implement a full CRUD in Express.js, we need to create routes that respond to each of the HTTP verbs mentioned above. In the context of the project we are going to develop (a booking system), this involves:

1. Create endpoints for each operation
2. Defining controllers that handle the business logic
3. Connecting to a database to persist the information
4. Test each endpoint using tools such as Postman.

Implementing these concepts will allow us to build a robust API that can be consumed by any client, be it a web application, mobile or even another service.

Basic example of a GET endpoint

app.get('/api/bookings', (req, res) => { // Logic to get all bookings res.json(bookings);});

This is just a simple example of how we could implement an endpoint to get information. In the next classes, we will go deeper into the implementation of each of the HTTP verbs to build our complete booking system.

What tools do we need to work with RESTful APIs?

To work efficiently with RESTful APIs, it is recommended to be familiar with:

• Postman: An essential tool to test our endpoints without the need to create a frontend.
• Express middleware: To handle authentication, validation and data processing.
• Data exchange formats: Mainly JSON, which has become the standard for web APIs.
• HTTP status codes: To correctly communicate the result of operations (200 OK, 201 Created, 404 Not Found, etc.).

Mastering these concepts will allow you to build robust and professional APIs that can be consumed by any type of client.

Creating RESTful APIs is a fundamental skill for any modern web developer. As we move forward in our booking system project, we will go deeper into each of these concepts and see how they apply in a real scenario. Do you have previous experience working with APIs? Share your experiences and doubts in the comments.