construprogress/app/Notifications/IssueCommentedNotification.php

<?php

namespace App\Notifications;

use App\Models\IssueComment;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Broadcasting\ShouldBroadcast;
use Illuminate\Notifications\Notification;
use Illuminate\Support\Str;

class IssueCommentedNotification extends Notification implements ShouldBroadcast
{
    use Queueable;

    public function __construct(public IssueComment $comment) {}

    public function via($notifiable): array
    {
        return ['database', 'broadcast'];
    }

    public function toArray($notifiable): array
    {
        $issue = $this->comment->issue;

        return [
            'type' => 'issue_commented',
            'issue_id' => $this->comment->issue_id,
            'project_id' => $issue?->project_id,
            'author' => $this->comment->user?->name,
            'message' => "{$this->comment->user?->name} comentó en '{$issue?->title}': ".Str::limit($this->comment->body, 60),
        ];
    }

    public function broadcastOn(): array
    {
        $issue = $this->comment->issue;
        $userIds = [];
        if ($issue->assigned_to) $userIds[] = $issue->assigned_to;
        if ($issue->reported_by) $userIds[] = $issue->reported_by;
        return array_map(fn ($id) => new \Illuminate\Broadcasting\PrivateChannel("user.{$id}"), array_unique($userIds));
    }
}