Resource controllers in Laravel

Introduction

Resource controllers help organize code by grouping related actions for a resource in one place. They make building web apps simpler and cleaner.

You want to handle all actions for a data type like users or posts in one controller.

You need to create, read, update, and delete items following a standard pattern.

You want Laravel to automatically create routes for common actions.

You want to keep your code easy to read and maintain.

You are building a RESTful API or web app with standard resource actions.

Syntax

Laravel

php artisan make:controller ResourceNameController --resource

This command creates a controller with methods for index, create, store, show, edit, update, and destroy.

You can register the controller routes with Route::resource('name', ResourceNameController::class);

Examples

Creates a ProductController with all resource methods.

Laravel

php artisan make:controller ProductController --resource

Registers routes for all resource actions like /products, /products/{id}, /products/create, etc.

Laravel

Route::resource('products', ProductController::class);

Example of a resource controller with index and show methods returning data.

Laravel

<?php

namespace App\Http\Controllers;

use App\Models\Product;
use Illuminate\Http\Request;

class ProductController extends Controller
{
    public function index() {
        return Product::all();
    }

    public function show(Product $product) {
        return $product;
    }

    // Other resource methods here...
}

Sample Program

This BookController handles all common actions for books. The routes created by Route::resource will call these methods automatically.

Laravel

<?php

namespace App\Http\Controllers;

use App\Models\Book;
use Illuminate\Http\Request;

class BookController extends Controller
{
    public function index() {
        return Book::all();
    }

    public function create() {
        return 'Show form to create a book';
    }

    public function store(Request $request) {
        $book = Book::create($request->all());
        return response()->json($book, 201);
    }

    public function show(Book $book) {
        return $book;
    }

    public function edit(Book $book) {
        return 'Show form to edit book with id ' . $book->id;
    }

    public function update(Request $request, Book $book) {
        $book->update($request->all());
        return response()->json($book);
    }

    public function destroy(Book $book) {
        $book->delete();
        return response()->json(null, 204);
    }
}

// Route registration example:
// Route::resource('books', BookController::class);

Important Notes

Resource controllers follow RESTful conventions, making your app predictable.

You can customize which methods to include by using only or except when registering routes.

Use route model binding to automatically get model instances in methods like show(Book $book).

Summary

Resource controllers group related actions for a resource in one controller.

Laravel can auto-generate routes for these actions with Route::resource.

This keeps your code organized and follows common web app patterns.

Practice

1. What is the main purpose of a resource controller in Laravel?

easy

A. To create views without a controller

B. To handle database migrations automatically

C. To group all CRUD actions for a resource in one controller

D. To manage user authentication only

Solution

1. Step 1: Understand what resource controllers do

   Resource controllers in Laravel group related actions like create, read, update, and delete (CRUD) for a resource in one controller class.

2. Step 2: Compare options with this definition

   Only To group all CRUD actions for a resource in one controller correctly describes this grouping of CRUD actions. Other options describe unrelated features.

3. Final Answer:

   To group all CRUD actions for a resource in one controller -> Option C

4. Quick Check:

   Resource controller = CRUD grouping [OK]

Hint: Resource controllers group CRUD actions in one place [OK]

Common Mistakes:

• Confusing resource controllers with migrations
• Thinking resource controllers handle views alone
• Assuming resource controllers manage authentication

2. Which of the following is the correct syntax to register a resource controller named PostController for the route /posts?

easy

A. Route::resource('posts', PostController::class);

B. Route::controller('posts', PostController::class);

C. Route::get('posts', PostController::resource());

D. Route::resource('PostController', 'posts');

Solution

1. Step 1: Recall Laravel resource route syntax

   The correct syntax uses Route::resource('uri', ControllerClass::class) to register all resource routes.

2. Step 2: Check each option

   Route::resource('posts', PostController::class); matches the correct syntax. Route::controller('posts', PostController::class); uses controller which is different. Route::get('posts', PostController::resource()); is invalid syntax. Route::resource('PostController', 'posts'); swaps parameters incorrectly.

3. Final Answer:

   Route::resource('posts', PostController::class); -> Option A

4. Quick Check:

   Resource route syntax = Route::resource(uri, Controller::class) [OK]

Hint: Use Route::resource('uri', Controller::class) to register resource routes [OK]

Common Mistakes:

• Using Route::controller instead of Route::resource
• Swapping URI and controller parameters
• Calling resource() as a method on controller instance

3. Given this resource controller route registration:
Route::resource('photos', PhotoController::class);
Which URL and HTTP method will call the destroy method in PhotoController for photo with ID 5?

medium

A. PUT /photos/5/destroy

B. GET /photos/5/destroy

C. POST /photos/5/delete

D. DELETE /photos/5

Solution

1. Step 1: Recall resource route conventions for destroy

   The destroy method is called with HTTP DELETE on the resource URI with the ID, e.g., DELETE /photos/{id}.

2. Step 2: Match options to this pattern

   DELETE /photos/5 matches DELETE /photos/5. Other options use wrong HTTP methods or incorrect URLs.

3. Final Answer:

   DELETE /photos/5 -> Option D

4. Quick Check:

   Destroy = DELETE /resource/{id} [OK]

Hint: Destroy uses DELETE method on /resource/{id} URL [OK]

Common Mistakes:

• Using GET or POST instead of DELETE for destroy
• Adding extra path segments like /destroy or /delete
• Confusing PUT with DELETE method

4. Consider this route registration:
Route::resource('users', UserController::class);
Which of the following code snippets will cause a runtime error when trying to access the show method?

medium

A. public function show() { return 'User not found'; }

B. public function show(User $user) { return $user; }

C. public function show($id) { return view('user.show', compact('id')); }

D. public function show($id) { return User::findOrFail($id); }

Solution

1. Step 1: Understand show method parameter requirements

   The show method expects either an ID parameter or a model instance via route model binding.

2. Step 2: Analyze each option

   public function show() { return 'User not found'; } has no parameter, so Laravel cannot pass the required ID or model, causing a runtime error. Others have correct parameters.

3. Final Answer:

   public function show() { return 'User not found'; } -> Option A

4. Quick Check:

   Show method must accept ID or model parameter [OK]

Hint: Show method needs parameter for ID or model [OK]

Common Mistakes:

• Omitting parameters in show method
• Using wrong parameter types without binding
• Ignoring route model binding requirements

5. You want to create a resource controller for Product but only want to generate routes for index, show, and store methods. Which is the correct way to register this in routes/web.php?

hard

A. Route::resource('products', ProductController::class)->except(['create', 'edit']);

B. Route::resource('products', ProductController::class)->only(['index', 'show', 'store']);

C. Route::resource('products', ProductController::class)->skip(['create', 'edit']);

D. Route::resource('products', ProductController::class)->filter(['index', 'show', 'store']);

Solution

1. Step 1: Recall how to limit resource routes

   Laravel allows limiting routes using the only method with an array of method names.

2. Step 2: Evaluate each option

   A uses except(['create', 'edit']) which excludes only create and edit, leaving index, store, show, update, and destroy. B correctly uses only(['index', 'show', 'store']). C and D use invalid methods skip and filter.

3. Final Answer:

   Route::resource('products', ProductController::class)->only(['index', 'show', 'store']); -> Option B

4. Quick Check:

   Limit resource routes with only([...]) [OK]

Hint: Use ->only([...]) to limit resource controller routes [OK]

Common Mistakes:

• Using invalid methods like skip or filter
• Confusing only with except
• Not passing array to only method