Domain.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Domain extends Model
{
    /**
     * The attributes that are mass assignable.
     *
     * @var array
     */
    protected $fillable = [
        'host',
        'user_id',
        'screenshot',
        'screenshot_updated'
    ];

    public static function boot()
    {
        parent::boot();

        //ensure we remove the scheme
        static::creating(function($domain){
            $domain->host = preg_replace("(^https?://)", "", $domain->host );
        });
    }

    public function users(){
        return $this->belongsToMany(User::class);
    }

    public function setPrimary(User $user){
        $this->user_id = $user->id;
    }

}