CallbackApiTest.php 2.45 KB
<?php namespace common\exts\wechat;

/**
 * Class WechatCallbackApiTest
 * @package common\exts\wechat
 */
class CallbackApiTest
{

    /**
     * @var string
     */
    private $token;

    /**
     * @param $token
     */
    public function __construct($token)
    {
        $this->token = $token;
    }

    /**
     *
     */
    public function valid()
    {
        $echoStr = isset($_GET["echostr"]) ? $_GET["echostr"] : '';

        //valid signature , option
        if($this->checkSignature()){
            echo $echoStr;
            exit;
        }
    }

    public function responseMsg()
    {
        //get post data, May be due to the different environments
        $postStr = $GLOBALS["HTTP_RAW_POST_DATA"];

        //extract post data
        if (!empty($postStr)){
            /* libxml_disable_entity_loader is to prevent XML eXternal Entity Injection,
               the best way is to check the validity of xml by yourself */
            libxml_disable_entity_loader(true);
            $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
            $fromUsername = $postObj->FromUserName;
            $toUsername = $postObj->ToUserName;
            $keyword = trim($postObj->Content);
            $time = time();
            $textTpl = "<xml>
							<ToUserName><![CDATA[%s]]></ToUserName>
							<FromUserName><![CDATA[%s]]></FromUserName>
							<CreateTime>%s</CreateTime>
							<MsgType><![CDATA[%s]]></MsgType>
							<Content><![CDATA[%s]]></Content>
							<FuncFlag>0</FuncFlag>
							</xml>";
            if(!empty( $keyword ))
            {
                $msgType = "text";
                $contentStr = "Welcome to wechat world!";
                $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);
                echo $resultStr;
            }else{
                echo "Input something...";
            }

        }else {
            echo "";
            exit;
        }
    }

    /**
     * @return bool
     */
    private function checkSignature()
    {

        $signature = $_GET["signature"];
        $timestamp = $_GET["timestamp"];
        $nonce = $_GET["nonce"];

        $tmpArr = array($this->token, $timestamp, $nonce);
        // use SORT_STRING rule
        sort($tmpArr, SORT_STRING);
        $tmpStr = implode( $tmpArr );
        $tmpStr = sha1( $tmpStr );

        if( $tmpStr == $signature ){
            return true;
        }else{
            return false;
        }
    }
}