1. Introduction

1.1 The Goals of This Tutorial

This tutorial aims to introduce you to the process of building RESTful APIs using Laravel. By the end of this tutorial, you will have built your own API and understand the fundamentals of Laravel API development.

1.2 What You'll Learn

You'll get hands-on experience:

• Setting up your Laravel environment
• Defining routes and controllers
• Handling HTTP requests and responses
• Implementing CRUD operations
• Validating inputs

1.3 Prerequisites

• Basic knowledge of PHP
• Familiarity with HTTP and REST
• Laravel, Composer and Postman installed on your computer

2. Step-by-Step Guide

2.1 Setting Up Laravel

First, let's create a new Laravel project. Open your terminal and type:

composer create-project --prefer-dist laravel/laravel blog

This will create a new Laravel project named blog.

2.2 Defining Routes

Routes in Laravel are defined in the routes/api.php file. Let's define a route for retrieving blog posts:

Route::get('/posts', 'PostController@index');

This means when we make a GET request to /posts, Laravel will execute the index method of PostController.

2.3 Creating the Controller

Now, let's generate the PostController:

php artisan make:controller PostController --api

This command creates a controller with methods for each API verb (index, show, store, update, delete).

3. Code Examples

3.1 CRUD Operations

Let's add logic to our controller for CRUD operations. We'll use Eloquent ORM, Laravel's built-in ORM.

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Post;

class PostController extends Controller
{
    // Show all posts
    public function index()
    {
        return Post::all();
    }

    // Store a new post
    public function store(Request $request)
    {
        return Post::create($request->all());
    }

    // Show a single post
    public function show(Post $post)
    {
        return $post;
    }

    // Update a post
    public function update(Request $request, Post $post)
    {
        $post->update($request->all());
        return $post;
    }

    // Delete a post
    public function destroy(Post $post)
    {
        $post->delete();
        return response()->json(null, 204);
    }
}

Each method corresponds to a CRUD operation and handles HTTP requests accordingly.

4. Summary

In this tutorial, you learned how to set up a Laravel project, define routes, create controllers, and implement CRUD operations. You are now able to build a RESTful API using Laravel.

5. Practice Exercises

5.1 Exercise 1

Create a new Laravel project and define routes for a resource other than Post. Generate a corresponding controller.

5.2 Exercise 2

In the controller you just created, implement the index and show methods to return all instances of your resource and a single instance, respectively.

5.3 Exercise 3

Complete the CRUD operations by adding store, update, and destroy methods to your controller.

For further practice, consider adding validation to your API endpoints, or adding additional functionality such as filtering or sorting.

Remember: The best way to learn is by doing. Happy coding!