Laravel Framework

Building a Complete CRUD Application

20 min Lesson 35 of 45

Introduction to CRUD Applications

CRUD stands for Create, Read, Update, Delete - the four basic operations for data management in any application. In this comprehensive lesson, we'll build a complete blog post management system that demonstrates best practices for Laravel development, including models, migrations, controllers, views, validation, file uploads, relationships, search, filtering, and pagination.

What We'll Build:

Blog post management system with full CRUD operations
Featured image uploads with validation
Category and tag relationships (many-to-many)
Rich text editor for post content
Search and filter functionality
Pagination with sorting options
Form validation and error handling
Authorization with policies

Step 1: Database Design and Migrations

First, let's create the database structure for our blog system:

# Create migrations
php artisan make:migration create_posts_table
php artisan make:migration create_categories_table
php artisan make:migration create_tags_table
php artisan make:migration create_post_tag_table

<?php
// database/migrations/xxxx_create_posts_table.php
use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

return new class extends Migration
{
    public function up()
    {
        Schema::create('posts', function (Blueprint $table) {
            $table->id();
            $table->foreignId('user_id')->constrained()->onDelete('cascade');
            $table->foreignId('category_id')->nullable()->constrained()->nullOnDelete();
            $table->string('title');
            $table->string('slug')->unique();
            $table->text('excerpt')->nullable();
            $table->longText('content');
            $table->string('featured_image')->nullable();
            $table->enum('status', ['draft', 'published', 'archived'])->default('draft');
            $table->timestamp('published_at')->nullable();
            $table->integer('views')->default(0);
            $table->timestamps();

            // Indexes for performance
            $table->index('status');
            $table->index('published_at');
            $table->index(['status', 'published_at']);
            $table->fullText(['title', 'content']);
        });
    }

    public function down()
    {
        Schema::dropIfExists('posts');
    }
};

<?php
// database/migrations/xxxx_create_categories_table.php
public function up()
{
    Schema::create('categories', function (Blueprint $table) {
        $table->id();
        $table->string('name');
        $table->string('slug')->unique();
        $table->text('description')->nullable();
        $table->timestamps();
    });
}

// database/migrations/xxxx_create_tags_table.php
public function up()
{
    Schema::create('tags', function (Blueprint $table) {
        $table->id();
        $table->string('name');
        $table->string('slug')->unique();
        $table->timestamps();
    });
}

// database/migrations/xxxx_create_post_tag_table.php
public function up()
{
    Schema::create('post_tag', function (Blueprint $table) {
        $table->foreignId('post_id')->constrained()->onDelete('cascade');
        $table->foreignId('tag_id')->constrained()->onDelete('cascade');
        $table->primary(['post_id', 'tag_id']);
    });
}

# Run migrations
php artisan migrate

Step 2: Creating Models with Relationships

# Create models
php artisan make:model Post
php artisan make:model Category
php artisan make:model Tag

<?php
// app/Models/Post.php
namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Support\Str;

class Post extends Model
{
    use HasFactory;

    protected $fillable = [
        'user_id', 'category_id', 'title', 'slug', 'excerpt',
        'content', 'featured_image', 'status', 'published_at', 'views'
    ];

    protected $casts = [
        'published_at' => 'datetime',
        'views' => 'integer',
    ];

    // Relationships
    public function user()
    {
        return $this->belongsTo(User::class);
    }

    public function category()
    {
        return $this->belongsTo(Category::class);
    }

    public function tags()
    {
        return $this->belongsToMany(Tag::class);
    }

    // Scopes
    public function scopePublished($query)
    {
        return $query->where('status', 'published')
            ->where('published_at', '<=', now());
    }

    public function scopeSearch($query, $search)
    {
        return $query->where(function($q) use ($search) {
            $q->where('title', 'like', "%{$search}%")
              ->orWhere('content', 'like', "%{$search}%")
              ->orWhereHas('tags', function($tagQuery) use ($search) {
                  $tagQuery->where('name', 'like', "%{$search}%");
              });
        });
    }

    public function scopeByCategory($query, $categoryId)
    {
        return $query->where('category_id', $categoryId);
    }

    // Accessors & Mutators
    public function getExcerptAttribute($value)
    {
        return $value ?: Str::limit(strip_tags($this->content), 150);
    }

    public function setTitleAttribute($value)
    {
        $this->attributes['title'] = $value;
        $this->attributes['slug'] = Str::slug($value);
    }

    // Helper methods
    public function isPublished()
    {
        return $this->status === 'published' && $this->published_at <= now();
    }

    public function incrementViews()
    {
        $this->increment('views');
    }
}

<?php
// app/Models/Category.php
namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Category extends Model
{
    protected $fillable = ['name', 'slug', 'description'];

    public function posts()
    {
        return $this->hasMany(Post::class);
    }
}

// app/Models/Tag.php
namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Tag extends Model
{
    protected $fillable = ['name', 'slug'];

    public function posts()
    {
        return $this->belongsToMany(Post::class);
    }
}

Step 3: Form Requests for Validation

# Create form request classes
php artisan make:request StorePostRequest
php artisan make:request UpdatePostRequest

<?php
// app/Http/Requests/StorePostRequest.php
namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;

class StorePostRequest extends FormRequest
{
    public function authorize()
    {
        return true; // Handle with policy
    }

    public function rules()
    {
        return [
            'title' => 'required|string|max:255|unique:posts,title',
            'category_id' => 'required|exists:categories,id',
            'excerpt' => 'nullable|string|max:500',
            'content' => 'required|string|min:100',
            'featured_image' => 'nullable|image|mimes:jpeg,png,jpg,webp|max:2048',
            'tags' => 'nullable|array',
            'tags.*' => 'exists:tags,id',
            'status' => 'required|in:draft,published,archived',
            'published_at' => 'nullable|date|after_or_equal:today',
        ];
    }

    public function messages()
    {
        return [
            'title.required' => 'Please enter a title for your post',
            'title.unique' => 'A post with this title already exists',
            'content.min' => 'Post content must be at least 100 characters',
            'featured_image.max' => 'Image size must not exceed 2MB',
            'category_id.exists' => 'Please select a valid category',
        ];
    }
}

// app/Http/Requests/UpdatePostRequest.php
namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;
use Illuminate\Validation\Rule;

class UpdatePostRequest extends FormRequest
{
    public function authorize()
    {
        return true;
    }

    public function rules()
    {
        return [
            'title' => [
                'required',
                'string',
                'max:255',
                Rule::unique('posts')->ignore($this->post->id)
            ],
            'category_id' => 'required|exists:categories,id',
            'excerpt' => 'nullable|string|max:500',
            'content' => 'required|string|min:100',
            'featured_image' => 'nullable|image|mimes:jpeg,png,jpg,webp|max:2048',
            'tags' => 'nullable|array',
            'tags.*' => 'exists:tags,id',
            'status' => 'required|in:draft,published,archived',
            'published_at' => 'nullable|date',
        ];
    }
}

Step 4: Controller with CRUD Operations

# Create controller
php artisan make:controller PostController --resource

<?php
// app/Http/Controllers/PostController.php
namespace App\Http\Controllers;

use App\Models\Post;
use App\Models\Category;
use App\Models\Tag;
use App\Http\Requests\StorePostRequest;
use App\Http\Requests\UpdatePostRequest;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Storage;

class PostController extends Controller
{
    public function __construct()
    {
        $this->middleware('auth')->except(['index', 'show']);
    }

    // Display listing with search, filter, sort
    public function index(Request $request)
    {
        $query = Post::with(['user', 'category', 'tags'])
            ->withCount('tags');

        // Search
        if ($search = $request->input('search')) {
            $query->search($search);
        }

        // Filter by category
        if ($categoryId = $request->input('category')) {
            $query->byCategory($categoryId);
        }

        // Filter by status
        if ($status = $request->input('status')) {
            $query->where('status', $status);
        } else {
            // Default: show only published posts for guests
            if (!auth()->check()) {
                $query->published();
            }
        }

        // Sort
        $sortBy = $request->input('sort', 'created_at');
        $sortOrder = $request->input('order', 'desc');
        $query->orderBy($sortBy, $sortOrder);

        $posts = $query->paginate(15)->withQueryString();

        $categories = Category::withCount('posts')->get();

        return view('posts.index', compact('posts', 'categories'));
    }

    // Show create form
    public function create()
    {
        $categories = Category::all();
        $tags = Tag::all();

        return view('posts.create', compact('categories', 'tags'));
    }

    // Store new post
    public function store(StorePostRequest $request)
    {
        $data = $request->validated();
        $data['user_id'] = auth()->id();

        // Handle file upload
        if ($request->hasFile('featured_image')) {
            $data['featured_image'] = $request->file('featured_image')
                ->store('posts', 'public');
        }

        // Set published_at if status is published
        if ($data['status'] === 'published' && !isset($data['published_at'])) {
            $data['published_at'] = now();
        }

        $post = Post::create($data);

        // Attach tags
        if ($request->has('tags')) {
            $post->tags()->attach($request->tags);
        }

        return redirect()->route('posts.show', $post)
            ->with('success', 'Post created successfully!');
    }

    // Display single post
    public function show(Post $post)
    {
        // Eager load relationships
        $post->load(['user', 'category', 'tags']);

        // Increment views
        $post->incrementViews();

        // Get related posts
        $relatedPosts = Post::published()
            ->where('category_id', $post->category_id)
            ->where('id', '!=', $post->id)
            ->limit(4)
            ->get();

        return view('posts.show', compact('post', 'relatedPosts'));
    }

    // Show edit form
    public function edit(Post $post)
    {
        $this->authorize('update', $post);

        $categories = Category::all();
        $tags = Tag::all();

        return view('posts.edit', compact('post', 'categories', 'tags'));
    }

    // Update post
    public function update(UpdatePostRequest $request, Post $post)
    {
        $this->authorize('update', $post);

        $data = $request->validated();

        // Handle file upload
        if ($request->hasFile('featured_image')) {
            // Delete old image
            if ($post->featured_image) {
                Storage::disk('public')->delete($post->featured_image);
            }

            $data['featured_image'] = $request->file('featured_image')
                ->store('posts', 'public');
        }

        // Set published_at if status changed to published
        if ($data['status'] === 'published' && !$post->published_at) {
            $data['published_at'] = now();
        }

        $post->update($data);

        // Sync tags
        if ($request->has('tags')) {
            $post->tags()->sync($request->tags);
        } else {
            $post->tags()->detach();
        }

        return redirect()->route('posts.show', $post)
            ->with('success', 'Post updated successfully!');
    }

    // Delete post
    public function destroy(Post $post)
    {
        $this->authorize('delete', $post);

        // Delete featured image
        if ($post->featured_image) {
            Storage::disk('public')->delete($post->featured_image);
        }

        $post->delete();

        return redirect()->route('posts.index')
            ->with('success', 'Post deleted successfully!');
    }
}

Step 5: Authorization with Policy

# Create policy
php artisan make:policy PostPolicy --model=Post

<?php
// app/Policies/PostPolicy.php
namespace App\Policies;

use App\Models\Post;
use App\Models\User;

class PostPolicy
{
    public function viewAny(?User $user)
    {
        return true;
    }

    public function view(?User $user, Post $post)
    {
        return $post->isPublished() || $user?->id === $post->user_id;
    }

    public function create(User $user)
    {
        return true; // All authenticated users can create
    }

    public function update(User $user, Post $post)
    {
        return $user->id === $post->user_id;
    }

    public function delete(User $user, Post $post)
    {
        return $user->id === $post->user_id;
    }
}

Step 6: Routes Configuration

<?php
// routes/web.php
use App\Http\Controllers\PostController;

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

// Additional custom routes if needed
Route::get('/posts/category/{category:slug}', [PostController::class, 'byCategory'])
    ->name('posts.by-category');

Route::get('/posts/tag/{tag:slug}', [PostController::class, 'byTag'])
    ->name('posts.by-tag');

Step 7: Views - Index Page

<!-- resources/views/posts/index.blade.php -->
@extends('layouts.app')

@section('content')
<div class="container">
    <div class="row">
        <div class="col-md-8">
            <h1>Blog Posts</h1>

            <!-- Search and Filter Form -->
            <form method="GET" class="mb-4">
                <div class="row">
                    <div class="col-md-6">
                        <input type="text" name="search" class="form-control"
                               placeholder="Search posts..." value="{{ request('search') }}">
                    </div>
                    <div class="col-md-4">
                        <select name="category" class="form-control">
                            <option value="">All Categories</option>
                            @foreach($categories as $category)
                                <option value="{{ $category->id }}"
                                    {{ request('category') == $category->id ? 'selected' : '' }}>
                                    {{ $category->name }} ({{ $category->posts_count }})
                                </option>
                            @endforeach
                        </select>
                    </div>
                    <div class="col-md-2">
                        <button type="submit" class="btn btn-primary w-100">Filter</button>
                    </div>
                </div>
            </form>

            <!-- Posts List -->
            @forelse($posts as $post)
                <article class="post-card mb-4">
                    @if($post->featured_image)
                        <img src="{{ asset('storage/' . $post->featured_image) }}"
                             alt="{{ $post->title }}" class="img-fluid">
                    @endif

                    <h2>
                        <a href="{{ route('posts.show', $post) }}">{{ $post->title }}</a>
                    </h2>

                    <div class="post-meta">
                        By {{ $post->user->name }}
                        | {{ $post->published_at->format('M d, Y') }}
                        | {{ $post->category->name }}
                        | {{ $post->views }} views
                    </div>

                    <p>{{ $post->excerpt }}</p>

                    <div class="post-tags">
                        @foreach($post->tags as $tag)
                            <span class="badge bg-secondary">{{ $tag->name }}</span>
                        @endforeach
                    </div>

                    @can('update', $post)
                        <a href="{{ route('posts.edit', $post) }}" class="btn btn-sm btn-warning">Edit</a>
                    @endcan
                </article>
            @empty
                <p>No posts found.</p>
            @endforelse

            <!-- Pagination -->
            {{ $posts->links() }}
        </div>

        <div class="col-md-4">
            <!-- Sidebar with categories -->
            <h3>Categories</h3>
            <ul class="list-group">
                @foreach($categories as $category)
                    <li class="list-group-item d-flex justify-content-between">
                        <a href="?category={{ $category->id }}">{{ $category->name }}</a>
                        <span class="badge bg-primary">{{ $category->posts_count }}</span>
                    </li>
                @endforeach
            </ul>
        </div>
    </div>
</div>
@endsection

Step 8: Create/Edit Form

<!-- resources/views/posts/form.blade.php (shared by create & edit) -->
<div class="row">
    <div class="col-md-8">
        <div class="mb-3">
            <label for="title" class="form-label">Title</label>
            <input type="text" name="title" id="title" class="form-control @error('title') is-invalid @enderror"
                   value="{{ old('title', $post->title ?? '') }}" required>
            @error('title')
                <div class="invalid-feedback">{{ $message }}</div>
            @enderror
        </div>

        <div class="mb-3">
            <label for="excerpt" class="form-label">Excerpt</label>
            <textarea name="excerpt" id="excerpt" rows="3"
                      class="form-control @error('excerpt') is-invalid @enderror">{{ old('excerpt', $post->excerpt ?? '') }}</textarea>
            @error('excerpt')
                <div class="invalid-feedback">{{ $message }}</div>
            @enderror
        </div>

        <div class="mb-3">
            <label for="content" class="form-label">Content</label>
            <textarea name="content" id="content" rows="15"
                      class="form-control @error('content') is-invalid @enderror" required>{{ old('content', $post->content ?? '') }}</textarea>
            @error('content')
                <div class="invalid-feedback">{{ $message }}</div>
            @enderror
        </div>
    </div>

    <div class="col-md-4">
        <div class="mb-3">
            <label for="status" class="form-label">Status</label>
            <select name="status" id="status" class="form-control" required>
                <option value="draft" {{ old('status', $post->status ?? 'draft') === 'draft' ? 'selected' : '' }}>Draft</option>
                <option value="published" {{ old('status', $post->status ?? '') === 'published' ? 'selected' : '' }}>Published</option>
                <option value="archived" {{ old('status', $post->status ?? '') === 'archived' ? 'selected' : '' }}>Archived</option>
            </select>
        </div>

        <div class="mb-3">
            <label for="category_id" class="form-label">Category</label>
            <select name="category_id" id="category_id" class="form-control @error('category_id') is-invalid @enderror" required>
                <option value="">Select Category</option>
                @foreach($categories as $category)
                    <option value="{{ $category->id }}"
                        {{ old('category_id', $post->category_id ?? '') == $category->id ? 'selected' : '' }}>
                        {{ $category->name }}
                    </option>
                @endforeach
            </select>
            @error('category_id')
                <div class="invalid-feedback">{{ $message }}</div>
            @enderror
        </div>

        <div class="mb-3">
            <label for="tags" class="form-label">Tags</label>
            <select name="tags[]" id="tags" class="form-control" multiple>
                @foreach($tags as $tag)
                    <option value="{{ $tag->id }}"
                        {{ in_array($tag->id, old('tags', $post->tags->pluck('id')->toArray() ?? [])) ? 'selected' : '' }}>
                        {{ $tag->name }}
                    </option>
                @endforeach
            </select>
        </div>

        <div class="mb-3">
            <label for="featured_image" class="form-label">Featured Image</label>
            @if(isset($post) && $post->featured_image)
                <img src="{{ asset('storage/' . $post->featured_image) }}" class="img-fluid mb-2">
            @endif
            <input type="file" name="featured_image" id="featured_image"
                   class="form-control @error('featured_image') is-invalid @enderror">
            @error('featured_image')
                <div class="invalid-feedback">{{ $message }}</div>
            @enderror
        </div>

        <div class="mb-3">
            <label for="published_at" class="form-label">Publish Date</label>
            <input type="datetime-local" name="published_at" id="published_at"
                   class="form-control"
                   value="{{ old('published_at', $post->published_at?->format('Y-m-d\TH:i') ?? '') }}">
        </div>

        <button type="submit" class="btn btn-primary w-100">
            {{ isset($post) ? 'Update Post' : 'Create Post' }}
        </button>
    </div>
</div>

Rich Text Editor: For a better content editing experience, integrate a WYSIWYG editor like TinyMCE, CKEditor, or Trix. Add the editor's JavaScript library and initialize it on the content textarea.

Practice Exercise 1: Add Comment System

Extend the blog application with a comment system:

Create Comment model with migration (post_id, user_id, content, parent_id for replies)
Set up relationships (post hasMany comments, comment belongsTo post/user)
Create CommentController with store/update/destroy methods
Add comment form to post show page
Display comments with nested replies
Implement comment approval system (approved column)
Add policies for comment management

Practice Exercise 2: Advanced Search with Filters

Enhance the search functionality:

Add date range filter (published between X and Y)
Add author filter dropdown
Implement tag filtering (show posts with selected tags)
Add sorting options (newest, oldest, most viewed, most commented)
Save filter preferences in session
Add "Clear Filters" button
Show active filters as removable badges

Practice Exercise 3: Post Analytics Dashboard

Create an analytics dashboard for post authors:

Total views per post (chart)
Views over time (line chart - last 30 days)
Most popular posts (top 10)
Category performance comparison
Engagement metrics (comments, likes if implemented)
Export analytics to CSV
Cache expensive analytics queries

Bonus: Use Chart.js or ApexCharts for visualizations.

Summary

Congratulations! You've built a complete CRUD application with Laravel. This lesson covered:

Database design with proper relationships and indexes
Creating models with Eloquent relationships and scopes
Form request validation with custom messages
Resource controller with full CRUD operations
File upload handling with validation
Authorization using policies
Search, filtering, and sorting functionality
Pagination with query string preservation
Blade views with forms and error handling
Many-to-many relationships with tags
Image storage and deletion
Best practices for Laravel development

This comprehensive application demonstrates production-ready patterns you can use in real-world projects. You now have the skills to build any CRUD-based application with Laravel, handling complex relationships, validation, authorization, and user interactions.