laravelio/laravel.io

// There's a mismatch with the folder name of "Helpers", but these are not global helpers, they are Traits

namespace App\Helpers;

trait HasSlug
{
    public function slug(): string
    {
        return $this->slug;
    }

    public function setSlugAttribute(string $slug)
    {
        $this->attributes['slug'] = $this->generateUniqueSlug($slug);
    }

    public static function findBySlug(string $slug): self
    {
        return static::where('slug', $slug)->firstOrFail();
    }

    private function generateUniqueSlug(string $value): string
    {
        $slug = $originalSlug = Str::slug($value) ?: Str::random(5);
        $counter = 0;

        while ($this->slugExists($slug, $this->exists ? $this->id() : null)) {
            $counter++;
            $slug = $originalSlug.'-'.$counter;
        }

        return $slug;
    }

    private function slugExists(string $slug, int $ignoreId = null): bool
    {
        $query = $this->where('slug', $slug);

        if ($ignoreId) {
            $query->where('id', '!=', $ignoreId);
        }

        return $query->exists();
    }
}

use App\Helpers\HasSlug;

final class Tag extends Model
{
    use HasSlug;

    // ... other Model code
}

use App\Helpers\HasSlug;

final class Article extends Model
{
    use HasSlug;

    // ... other Model code
}

// This file overrides the default Laravel Route Model Binding with other rules
//   including findBySlug() that comes from the HasSlug Trait

Route::bind('tag', function (string $slug) {
    return App\Models\Tag::findBySlug($slug);
});
Route::bind('article', function (string $slug) {
    return App\Models\Article::findBySlug($slug);
});