php-wechat-sdk/src/Wechat/Work/Message.php

<?php

namespace Wechat\Work;

use Wechat\Work\MessageInterface;

class Message
{

    /**
     * @var Work
     */
    protected $work;

    public function __construct($work)
    {
        $this->work = $work;
    }

    public function send($msg)
    {
        $request = $this->work->transformForJsonRequest('message/send',
            $msg->toArray() + ['agentid' => $this->work->getAgentId()]);
        return $this->work->request($request);
    }
}