How to use Discord webhooks

DiscordChannel.php

<?php

namespace App\Services\NotificationChannels\Discord;

use GuzzleHttp\Client;
use GuzzleHttp\RequestOptions;
use Illuminate\Notifications\Notification;

class DiscordChannel
{
    public function send($notifiable, Notification $notification)
    {
        $discordMessage = $notification->toDiscord();

        $discordWebhook = $notifiable->destination['url'];

        (new Client())->post($discordWebhook, [
            RequestOptions::JSON => $discordMessage->toArray(),
        ]);
    }
}

DiscordMessage.php

<?php

namespace App\Services\NotificationChannels\Discord;

use Carbon\Carbon;

class DiscordMessage
{
    const COLOR_SUCCESS = '#0B6623';
    const COLOR_WARNING = '#FD6A02';
    const COLOR_ERROR = '#ED2939';

    /** @var string */
    protected $title;

    /** @var string */
    protected $description;

    /** @var string */
    protected $timestamp;

    /** @var string */
    protected $footer;

    /** @var string */
    protected $color;

    public function title($title)
    {
        $this->title = $title;

        return $this;
    }

    /**
     * @param array|string $descriptionLines
     *
     * @return \App\Services\NotificationChannels\Discord\DiscordMessage
     */
    public function description($descriptionLines): self
    {
        if (! is_array($descriptionLines)) {
            $descriptionLines = [$descriptionLines];
        }

        $this->description = implode(PHP_EOL, $descriptionLines);

        return $this;
    }

    public function timestamp(Carbon $carbon): self
    {
        $this->timestamp = $carbon->toIso8601String();

        return $this;
    }

    public function footer(string $footer): self
    {
        $this->footer = $footer;

        return $this;
    }

    public function success(): self
    {
        $this->color = static::COLOR_SUCCESS;

        return $this;
    }

    public function warning(): self
    {
        $this->color = static::COLOR_WARNING;

        return $this;
    }

    public function error(): self
    {
        $this->color = static::COLOR_ERROR;

        return $this;
    }

    public function toArray(): array
    {
        return [
            'embeds' => [
                [
                    'title' => $this->title,
                    'type' => 'rich',
                    'description' => $this->description,
                    'color' => hexdec($this->color),
                    'footer' => [
                        'text' => $this->footer ?? '',
                    ],
                    'timestamp' => $this->timestamp,
                ],
            ],
        ];
    }
}

UptimeCheckFailed.php

<?php

namespace App\Services\Checkers\Uptime\Notifications;

use App\Models\NotificationLogItem;
use App\Services\Checkers\Notification;
use App\Services\NotificationChannels\Discord\DiscordMessage;
use Carbon\Carbon;

class UptimeCheckFailed extends Notification
{
    ...

    public function toDiscord()
    {
        return (new DiscordMessage())
            ->error()
            ->title($this->getMainMessage())
            ->description([
                $this->run->checkerResult()->getErrorDescription(),
                'Full report: ' . $this->run->result_url,
            ])
            ->footer("Downtime verified from {$this->run->usedUptimeCheckerLocations()}")
            ->timestamp(Carbon::now());
    }

    ...
}