首先修改配置,需要填写服务器地址(URL,注意加上http://前缀)、Token和EncodingAESKey,其中URL是开发者用来接收微信消息和事件的接口URL。Token可由开发者可以任意填写,用作生成签名(该Token会和接口URL中包含的Token进行比对,从而验证安全性)。EncodingAESKey由开发者手动填写或随机生成,将用作消息体加解密密钥。
开发者提交信息后,微信服务器将发送GET请求到填写的服务器地址URL上,参数有四个:
开发者通过检验signature对请求进行校验(下面有校验方式)。若确认此次GET请求来自微信服务器,请原样返回echostr参数内容,则接入生效,成为开发者成功,否则接入失败。加密/校验流程如下:
1)将token、timestamp、nonce三个参数进行字典序排序
2)将三个参数字符串拼接成一个字符串进行sha1加密
3)开发者获得加密后的字符串可与signature对比,标识该请求来源于微信
PHP示例代码:
接通两个服务器:
define("TOKEN", "weixin"); $wechatObj = new wechatCallbackapiTest(); $wechatObj->run(); class wechatCallbackapiTest{ public function run(){ if ($this->checkSignature() == false) { die('非法请求'); } if (isset($_GET['echostr'])) { $echoStr = $_GET['echostr']; echo $echoStr; exit; }else{ $this->responseMsg(); } }
设置自动回复消息
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)){ $postObj = simplexml_load_string($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; } }
判断请求是否来自微信
private function checkSignature() { $signature = $_GET["signature"]; $timestamp = $_GET["timestamp"]; $nonce = $_GET["nonce"]; $token = TOKEN; $tmpArr = array($token, $timestamp, $nonce); sort($tmpArr); $tmpStr = implode( $tmpArr ); $tmpStr = sha1( $tmpStr ); if( $tmpStr == $signature ){ return true; }else{ return false; } }