messageApplet/serviceApi/application/index/controller/Weichatcallbackapi.php

<?php
/**
 * Created by PhpStorm.
 * User: Titan 名字就是密码
 * Date: 2019/12/13
 * Time: 11:19
 */

namespace app\index\controller;

define("TOKEN","titan666");

class Weichatcallbackapi
{

    public function valid()
    {
        $echoStr = $_GET["echostr"];

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

    private function checkSignature()
    {
    	$signature = $_GET["signature"];
		$timestamp = $_GET["timestamp"];
		$nonce = $_GET["nonce"];
		$token = TOKEN;
		$tmpArr = array($token, $timestamp, $nonce);
	    sort($tmpArr, SORT_STRING);
	    $tmpStr = implode( $tmpArr );
	    $tmpStr = sha1( $tmpStr );
	
	    if ($tmpStr == $signature ) {
	        return true;
	    } else {
	        return false;
	    }
    }
}