• <button open-type="contact" class='contactService' session-from="{{'https://https://mp.weixin.qq.com/debug/wxadoc/introduction/image/x11.png'}}" hover-class="none">聯絡客服獲取二維碼</button> 

• 當用戶在客服會話傳送訊息（或進行某些特定的使用者操作引發的事件推送時），微信伺服器會將訊息（或事件）的資料包（JSON或者XML格式）POST請求開發者填寫的URL。開發者收到請求後可以使用傳送客服訊息介面進行非同步回覆。

• 微信伺服器在將使用者的訊息發給小程式的開發者伺服器地址（開發設定處配置）後，微信伺服器在五秒內收不到響應會斷掉連線，並且重新發起請求，總共重試三次，如果在除錯中，發現使用者無法收到響應的訊息，可以檢查是否訊息處理超時。關於重試的訊息排重，有msgid的訊息推薦使用msgid排重。事件型別訊息推薦使用FromUserName + CreateTime 排重。

• 伺服器收到請求必須做出下述回覆，這樣微信伺服器才不會對此作任何處理，並且不會發起重試，否則，將出現嚴重的錯誤提示。詳見下面說明：

  1、直接回復success（推薦方式）
  2、直接回復空串（指位元組長度為0的空字串，而不是結構體中content欄位的內容為空）
   
  

• 一旦遇到以下情況，微信都會在小程式會話中，向用戶下發系統提示“該小程式客服暫時無法提供服務，請稍後再試”：

  1、開發者在5秒內未回覆任何內容
  2、開發者回覆了異常資料
  

• 訊息推送配置

• 填寫伺服器配置

• 驗證訊息的確來自微信伺服器

• 

  開發者提交資訊後，微信伺服器將傳送GET請求到填寫的伺服器地址URL上，GET請求攜帶引數如下表所示：

  點選提交認證的時候，需要呼叫到如下方法，進行校驗，校驗通過，代表配置成功
• //例項化物件
      $vyuanCustom = new vyuanCustomAPI();
      //注意：第一步驗證時開啟，驗證完成之後就可以註釋了
      $vyuanCustom->isValid();

• 詳細程式碼解析

<?php
    //伺服器配置介面地址 
    define("TOKEN", "vyuan");       //定義token
    define("WXPAY_APPID", '***********');     //替換為自己的APPID
    define("WXPAY_APPSECRET", '******************'); //替換為自己的APPSECRET

    class vyuanCustomAPI{        
        //用於小程式後臺第一步驗證返回，驗證成功後便可註釋
        public function isValid(){
            $echoStr = $_GET["echostr"];
            if ($this->checkSignature()) {
                echo $echoStr;
                exit;
            }
        }
        
        //官方提供的驗證demo
        public 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;
            }
        }
        
        //傳送訊息介面呼叫
        public function send($data){
            $url = "https://api.weixin.qq.com/cgi-bin/message/custom/send?access_token=".$this->getAccessToken();
            $data = urldecode(json_encode($data));
            $this->curl_post($url,$data);
        }
        
        //xml資料轉陣列
        public function xml2Array($contents = NULL, $encoding = 'UTF-8', $get_attributes = 1, $priority = 'tag'){
            if (!$contents){
                return array();
            }

            if (!function_exists('xml_parser_create')){
                return array ();
            }

            $parser = xml_parser_create('');
            xml_parser_set_option($parser, XML_OPTION_TARGET_ENCODING, $encoding);
            xml_parser_set_option($parser, XML_OPTION_CASE_FOLDING, 0);
            xml_parser_set_option($parser, XML_OPTION_SKIP_WHITE, 1);
            xml_parse_into_struct($parser, trim($contents), $xml_values);
            xml_parser_free($parser);
            
            if (!$xml_values) return array(); 
            $xml_array = array ();
            $parents = array ();
            $opened_tags = array ();
            $arr = array ();
            $current = & $xml_array;
            $repeated_tag_index = array (); 
            foreach ($xml_values as $data){
                unset ($attributes, $value);
                extract($data);
                $result = array ();
                $attributes_data = array ();
                if (isset ($value)){
                    if ($priority == 'tag')
                        $result = trim($value);
                    else
                        $result['value'] = trim($value);
                }
                
                if (isset ($attributes) && $get_attributes) {
                    foreach ($attributes as $attr => $val){
                        if ($priority == 'tag')
                            $attributes_data[$attr] = $val;
                        else
                            $result['attr'][$attr] = $val;
                    }
                }

                if ($type == "open"){ 
                    $parent[$level -1] = & $current;
                    if (!is_array($current) || (!in_array($tag, array_keys($current)))) {
                        $current[$tag] = $result;
                        if ($attributes_data)
                            $current[$tag . '_attr'] = $attributes_data;
                        $repeated_tag_index[$tag . '_' . $level] = 1;
                        if (isset($tag) && $tag && isset($current[$tag])) {
                            $current = & $current[$tag];
                        }
                    }else{
                        if (isset ($current[$tag][0])){
                            $current[$tag][$repeated_tag_index[$tag . '_' . $level]] = $result;
                            $repeated_tag_index[$tag . '_' . $level]++;
                        }else{ 
                            $current[$tag] = array (
                                $current[$tag],
                                $result
                            ); 
                            $repeated_tag_index[$tag . '_' . $level] = 2;
                            if (isset ($current[$tag . '_attr'])){
                                $current[$tag]['0_attr'] = $current[$tag . '_attr'];
                                unset ($current[$tag . '_attr']);
                            }
                        }
                        $last_item_index = $repeated_tag_index[$tag . '_' . $level] - 1;
                        $current = & $current[$tag][$last_item_index];
                    }
                }elseif ($type == "complete"){
                    if (!isset ($current[$tag])){
                        $current[$tag] = $result;
                        $repeated_tag_index[$tag . '_' . $level] = 1;
                        if ($priority == 'tag' && $attributes_data) {
                            $current[$tag . '_attr'] = $attributes_data;
                        }
                    }else{
                        if (isset ($current[$tag][0]) && is_array($current[$tag])) {
                            $current[$tag][$repeated_tag_index[$tag . '_' . $level]] = $result;
                            if ($priority == 'tag' && $get_attributes && $attributes_data) {
                                $current[$tag][$repeated_tag_index[$tag . '_' . $level] . '_attr'] = $attributes_data;
                            }
                            $repeated_tag_index[$tag . '_' . $level]++;
                        }else{
                            $current[$tag] = array (
                                $current[$tag],
                                $result
                            ); 
                            $repeated_tag_index[$tag . '_' . $level] = 1;
                            if ($priority == 'tag' && $get_attributes) {
                                if (isset ($current[$tag . '_attr']) && is_array($current[$tag])){ 
                                    $current[$tag]['0_attr'] = $current[$tag . '_attr'];
                                    unset ($current[$tag . '_attr']);
                                }
                                if ($attributes_data){
                                    $current[$tag][$repeated_tag_index[$tag . '_' . $level] . '_attr'] = $attributes_data;
                                }
                            }
                            $repeated_tag_index[$tag . '_' . $level]++; 
                        }
                    }
                }elseif ($type == 'close'){
                    $current = & $parent[$level -1];
                }
            }
            return ($xml_array);
        }

        //獲取accesstoken
        public function getAccessToken() {
            $tokenFile = "access_token.txt";
            $data = json_decode(file_get_contents($tokenFile,FILE_USE_INCLUDE_PATH));
            //accesstoken有效期是7200秒，這裡用到的檔案快取
            //注意：檔案許可權問題
            if (!$data->expire_time || $data->expire_time < time()) {
              
                $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=".WXPAY_APPID."&secret=".WXPAY_APPSECRET;
                
                $res =  json_decode(file_get_contents($url));
                if($res) {
                    $arr = array();
                    $access_token = $res->access_token;
                    $arr['expire_time'] = time() + 7000;
                    $arr['access_token'] = $access_token;
                    $fp = fopen($tokenFile, "w");
                    fwrite($fp, json_encode($arr));
                    fclose($fp);
                }
            } else {
                $access_token = $data->access_token;
            }
            
            return $access_token;
        }

        //post傳送json資料
        public function curl_post($url,$post_data){
            $ch = curl_init();
            curl_setopt($ch, CURLOPT_URL, $url);
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
            curl_setopt($ch, CURLOPT_POST, 1);
            curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);
            $res = curl_exec($ch);
            
            if(!$res){
                throw new Exception('傳送訊息失敗:'.curl_error($ch));
            }
            curl_close($ch);
        }  
        
        //進入客服視窗，如果需要主動發起客服訊息型別為圖片，則需要獲取media_id
        public function getMedia_id($imageurl){
             $foldername = date('Y-m-d',time()); //定義資料夾目錄
             $path = __DIR__.'/static/image/Code/'.$foldername.'/'; //伺服器存放目錄
             if(!is_dir($path)){
                 mkdir($path,0777,true);
             }else{
                 chmod($path,0777);
             }

             //下載二維碼到本地
             $imageInfo = $this -> getImage($imageurl,$path);
             $imageurl = $imageInfo['save_path'];
                    
             $post_url = "https://api.weixin.qq.com/cgi-bin/media/upload?access_token={$this->getAccessToken()}&type=image";
             $ch = curl_init();
             curl_setopt($ch, CURLOPT_URL, $post_url);
             curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
             curl_setopt($ch, CURLOPT_POST, 1);
             curl_setopt($ch, CURLOPT_POSTFIELDS, ['media'=>'@'.$imageurl]);
             $res = curl_exec($ch);
             $a = json_decode($res);

             $media_id = $a->media_id;
            return $media_id;
        }

        //下載二維碼
        public function getImage($url,$save_dir,$filename='',$type=0){
            if(trim($url)==''){
                return array('file_name'=>'','save_path'=>'','error'=>1);
            }
            if(trim($filename)==''){//儲存檔名
                $ext=strrchr($url,'.');
                if($ext!='.gif'&&$ext!='.jpg'){
                    return array('file_name'=>'','save_path'=>'','error'=>3);
                }
                $filename=time().$ext;
            }
            //獲取遠端檔案所採用的方法
            if($type){
                $ch=curl_init();
                $timeout=5;
                curl_setopt($ch,CURLOPT_URL,$url);
                curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
                curl_setopt($ch,CURLOPT_CONNECTTIMEOUT,$timeout);
                $img=curl_exec($ch);
                curl_close($ch);
            }else{
                ob_start();
                readfile($url);
                $img=ob_get_contents();
                ob_end_clean();
            }
    
            //下載檔案
            [email protected]($save_dir.$filename,'a');
            fwrite($fp2,$img);
            fclose($fp2);
            unset($img,$url);
            return array('file_name'=>$filename,'save_path'=>$save_dir.$filename,'error'=>0);
          }
    };
    
    //例項化物件
    $vyuanCustom = new vyuanCustomAPI();
    //注意：第一步驗證時開啟，驗證完成之後就可以註釋了
    $vyuanCustom->isValid();

    if($vyuanCustom->checkSignature() === true){
        $xmlstring = file_get_contents("php://input");
        $accept_info = $vyuanCustom->xml2Array($xmlstring)['xml'];
        
        if($accept_info){
            $ToUserName = $accept_info['ToUserName'];
            $FromUserName = $accept_info['FromUserName'];
            $CreateTime = $accept_info['CreateTime'];
            $MsgType = $accept_info['MsgType'];

            $data = array();
            if($MsgType == 'text'){//接收文字
                $Content = $accept_info['Content'];//文字內容
                $data['touser'] = $FromUserName;
                
                if($Content === '圖文') {
                    $data['msgtype'] = 'link';
                    $data['link']['title'] = urlencode('文章標題');
                    $data['link']['description'] = urlencode('好文章要分享');
                    $data['link']['url'] = 'https://segmentfault.com';
                    $data['link']['thumb_url'] = 'https://static.segmentfault.com/v-5a7c12fe/global/img/logo-b.svg';
                }else if($Content === '1'){
                    $data['msgtype'] = 'image';
                    $data['image']['media_id'] = 'q3oQpLPWOIB50tCKdR510qeNIGEQd9A0Ku7DJJmsTsXVeQZqq0sUMK2gbUyJZsYn';
                    $data['image']['picurl'] = 'this is image';
                }else if($Content === '2'){
                    $data['msgtype'] = 'text';
                    $data['text']['content'] = urlencode('你好');//urlencode 解決中文亂碼問題
                    
                }else{
                    $data['msgtype'] = 'text';
                    $data['text']['content'] = urlencode('對不起，我不知道您在說什麼....');//urlencode 解決中文亂碼問題
                }
                
                $vyuanCustom->send($data);exit;
                
            }else if($MsgType === 'image') {//接收圖片
                

            }else if($MsgType === 'event') {//進入客服視窗事件
                $Event = $accept_info['Event'];
                $SessionFrom = $accept_info['SessionFrom'];  //得到開發者在客服會話按鈕設定的session-from屬性

                $media_id = $vyuanCustom -> getMedia_id($SessionFrom);

                if($Event == 'user_enter_tempsession') {
                    $data['touser'] = $FromUserName;

                    if(!$media_id){
                        //紅娘二維碼不為空，傳送二維碼
                        $data['msgtype'] = 'image';
                        $data['image']['media_id'] = $media_id;
                        //$data['image']['media_id'] = 'D6SA5xGFDlrxspT2LovHD2gbMHrUjhcji7B6WUXZ2lG7rhWi4K8ExT0_6FF4uvJY';
                        $data['image']['picurl'] = 'this is image';
                    }else{
                        //紅娘二維碼為空，則傳送文字
                        $data['msgtype'] = 'text';
                        $data['text']['content'] = urlencode('您好，請回復1獲取我的微信');//urlencode 解決中文亂碼問題
                    }
                    
                    $vyuanCustom->send($data);exit;
                }
            }
            
            echo '<xml><ToUserName><![CDATA['.$FromUserName.']]></ToUserName><FromUserName><![CDATA['.$ToUserName.']]></FromUserName><CreateTime>'.$CreateTime.'</CreateTime><MsgType><![CDATA[transfer_customer_service]]></MsgType></xml>';
        }
    }