laravel-app/app/Models/Post.php

<?php

namespace App\Models;

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

class Post extends Model
{
    //
    use HasFactory;

    protected $fillable = [
        'user_id',
        'title',
        'slug',
        'content',
        'is_published',
        'published_at',
        'scheduled_at',
    ];

    protected $casts = [
        'published_at' => 'datetime',
        'scheduled_at' => 'datetime',
        'is_published' => 'boolean',
    ];

    public function comments() 
    {
        return $this->hasMany(Comment::class);    
    }

    public function scopePublished($query) 
    {
        return $query->where('is_published', true);
    }    
}