PHP를 사용하여 공개 계정의 자동 응답 기능을 구현하는 방법

<?php
    $postStr = $GLOBALS["HTTP_RAW_POST_DATA"];
    if (!empty($postStr)){
        $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
        $fromUser = $postObj->FromUserName;
        $toUser = $postObj->ToUserName;
        $msgType = $postObj->MsgType;
        $content = $postObj->Content;
        
        // 在这里可以对接收到的消息进行处理
        
        // 构造回复消息
        $replyText = "你发送的消息是：" . $content;
        $replyMsg = sprintf("
            <xml>
                <ToUserName><![CDATA[%s]]></ToUserName>
                <FromUserName><![CDATA[%s]]></FromUserName>
                <CreateTime>%s</CreateTime>
                <MsgType><![CDATA[text]]></MsgType>
                <Content><![CDATA[%s]]></Content>
            </xml>", $fromUser, $toUser, time(), $replyText);
        
        // 输出回复消息
        echo $replyMsg;
    }
?>

// 文本消息回复
function replyTextMessage($fromUser, $toUser, $content){
    $replyText = "你发送的消息是：" . $content;
    $replyMsg = sprintf("
        <xml>
            <ToUserName><![CDATA[%s]]></ToUserName>
            <FromUserName><![CDATA[%s]]></FromUserName>
            <CreateTime>%s</CreateTime>
            <MsgType><![CDATA[text]]></MsgType>
            <Content><![CDATA[%s]]></Content>
        </xml>", $fromUser, $toUser, time(), $replyText);
        
    echo $replyMsg;
}

// 图片消息回复
function replyImageMessage($fromUser, $toUser, $mediaId){
    $replyMsg = sprintf("
        <xml>
            <ToUserName><![CDATA[%s]]></ToUserName>
            <FromUserName><![CDATA[%s]]></FromUserName>
            <CreateTime>%s</CreateTime>
            <MsgType><![CDATA[image]]></MsgType>
            <Image>
                <MediaId><![CDATA[%s]]></MediaId>
            </Image>
        </xml>", $fromUser, $toUser, time(), $mediaId);
        
    echo $replyMsg;
}