Minimal APIs in ASP.NET Core: Compare With Controller

Enter Minimal APIs in ASP.NET Core, a lightweight and streamlined approach to building web applications. In this detailed blog, we'll explore the concept of Minimal APIs, understand why they matter, and walk through their implementation in ASP.NET Core.

Introduction

In the ever-evolving landscape of web development, simplicity is key. Enter Minimal APIs in ASP.NET Core, a lightweight and streamlined approach to building web applications. In this detailed blog, we'll explore the concept of Minimal APIs, understand why they matter, and walk through their implementation in ASP.NET Core.

What are Minimal APIs?

Minimal APIs are a simplified way of building web APIs in ASP.NET Core. They are designed for scenarios where you need a quick and minimalistic approach to expose endpoints without the overhead of a full-fledged MVC application.

Why Minimal APIs?

Traditional ASP.NET Core applications, especially those built with MVC, come with a considerable amount of boilerplate code. For scenarios where simplicity and brevity are paramount, Minimal APIs provide a cleaner and more concise alternative.

How Minimal APIs Work?

Minimal APIs leverage the WebApplication class to define routes and handle HTTP requests. They rely on a functional approach, allowing developers to define endpoints using lambda expressions.

When to Use Minimal APIs?

Minimal APIs are well-suited for small to medium-sized projects, microservices, or scenarios where a lightweight and focused API is sufficient. They shine in cases where rapid development and minimal ceremony are top priorities.

Creating a Minimal API in ASP.NET Core

Let's walk through the steps to create a minimal API in ASP.NET Core. We'll use Visual Studio Code for a lightweight development experience.

1. Create a New Project

Open a terminal and run the following commands.

dotnet new web -n MinimalApiDemo
cd MinimalApiDemo
code .

2. Define a Minimal API

In the Program.cs file, configure the WebApplication.

var builder = WebApplication.CreateBuilder(args);

var app = builder.Build();

app.MapGet("/", () => "Hello, Minimal API!");

app.Run();

This code defines a simple endpoint that responds with "Hello, Minimal API!" when the root path is accessed.

3. Run the Application

Execute the following command in the terminal.

dotnet run

Visit https://localhost:5001 in your browser or a tool like Curl to see the response.

Let's compare a simple controller-based API and a minimal API in ASP.NET Core with code snippets to illustrate the differences. We'll use the same "Hello, API!" example for both cases.

Controller-Based API

// HelloController.cs

using Microsoft.AspNetCore.Mvc;

[ApiController]
[Route("api/[controller]")]
public class HelloController : ControllerBase
{
    [HttpGet]
    public IActionResult Get()
    {
        return Ok("Hello, API!");
    }
}

Explanation

• The HelloController inherits from ControllerBase, a base class for API controllers in ASP.NET Core.
• The [ApiController] attribute adds some default behaviors suitable for APIs.
• The [Route] attribute specifies the route template for the controller.
• The Get method is an HTTP GET endpoint returning "Hello, API!".

Minimal API

// Program.cs

var builder = WebApplication.CreateBuilder(args);

var app = builder.Build();

app.MapGet("/api/hello", () => "Hello, API!");

app.Run();

In this minimal API example

• We use the WebApplication.CreateBuilder method to create a minimal web application.
• The app.MapGet method is used to define an HTTP GET endpoint at the specified route ("/api/hello").
• The lambda expression inside MapGet defines the response for the endpoint.

Comparison

• Boilerplate

  • The controller-based API involves more boilerplate code with class declarations, attributes, and method signatures.
  • The minimal API is more concise, with fewer abstractions.

• Flexibility

  • Controllers offer more features, routing capabilities, and support for features like model binding and action filters.
  • Minimal APIs are lightweight and suitable for scenarios where simplicity is crucial.

• Separation of Concerns

  • Controllers follow a more structured approach with methods grouped in classes, offering a clear separation of concerns.
  • Minimal APIs use a functional approach with direct route-to-handler mapping.

• Development Style

  • Controllers follow a class-based development style, which may be familiar to developers accustomed to object-oriented programming.
  • Minimal APIs use a functional and declarative style, suitable for scenarios where a quick and lightweight solution is preferred.

Advantages of Minimal APIs

1. Reduced Boilerplate: Minimal APIs eliminate much of the boilerplate code associated with traditional ASP.NET Core applications, resulting in cleaner and more focused code.
2. Quick Development: Developers can quickly define endpoints and handle HTTP requests using a succinct syntax, facilitating rapid development.
3. Lightweight Footprint: Minimal APIs have a minimal footprint, making them ideal for resource-efficient scenarios and microservices.
4. Focused Scenarios: They are tailored for scenarios where a full MVC framework might be overkill, providing a more targeted solution.

Conclusion

As web development continues to evolve, Minimal APIs in ASP.NET Core usher in a new era of simplicity. Embracing a functional and lightweight approach, they empower developers to build focused APIs with minimal ceremony. Whether you're working on a small project, a microservice, or exploring the beauty of concise code, Minimal APIs offer a refreshing and efficient solution in the ASP.NET Core ecosystem.

Happy coding!