tissue/app/User.php

<?php

namespace App;

use Illuminate\Notifications\Notifiable;
use Illuminate\Foundation\Auth\User as Authenticatable;

class User extends Authenticatable
{
    use Notifiable;

    /**
     * The attributes that are mass assignable.
     *
     * @var array
     */
    protected $fillable = [
        'name', 'email', 'password',
        'is_protected', 'accept_analytics',
        'display_name', 'description',
        'twitter_id', 'twitter_name',
    ];

    /**
     * The attributes that should be hidden for arrays.
     *
     * @var array
     */
    protected $hidden = [
        'password', 'remember_token',
    ];

    /**
     * このユーザのメールアドレスから、Gravatarの画像URLを生成します。
     * @param int $size 画像サイズ
     * @return string Gravatar 画像URL
     */
    public function getProfileImageUrl($size = 30) : string {
        $hash = md5(strtolower(trim($this->email)));
        return '//www.gravatar.com/avatar/' . $hash . '?s=' . $size;
    }
}