小程序接入客服消息，客服消息转发到网页版客服工具。

摘要：小程序接入客服消息消息推送配置填写等。特别要注意的是数据格式的选择为了后续其他信息能够转发回微信自有网页版客服消息平台，建议选择格式。

填写URL、Token等。

特别要注意的是：数据格式的选择；

为了后续其他信息能够转发回微信自有网页版客服消息平台，建议选择xml格式。
json格式现在还有bug(2018.3.5)，

bug主要原因返回的头部不符合http标准。
返回json格式header头应该是

Content-Type:application/json,

而微信的选json还是

Content-Type:text/xml，

checkSignature()) {
            echo $echoStr;
            exit;
        }
    }
    
    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;
        }
    }
    
    
    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数据转数组
    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] = $val; //Set all the attributes in a array called "attr"
                }
            }
            if ($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 . "_" . $level]++; //0 and 1 index is already taken
                    }
                }
            }
            elseif ($type == "close")
            {
                $current = & $parent[$level -1];
            }
        }
        return ($xml_array);
    }



    //获取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，这里用到的文件缓存
        //注意：文件权限问题
        if (!$data->expire_time || $data->expire_time < time()) {
          
            $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=".self::APP_ID."&secret=".self::APP_SECRET;
            
            $res =  json_decode(file_get_contents($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 $access_token;
    }
    //post发送json数据
    public function curl_post($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(!$res){
            throw new Exception("发送消息失败:".curl_error($ch));
        }
        curl_close($ch);
    }

    

  
};


$wechatObj = new wechatAPI();

//注意：第一步验证时打开，验证完成之后就可以注释了
// $wechatObj->isValid();

if($wechatObj->checkSignature() === true){

    $xmlstring = file_get_contents("php://input");
    $accept_info = $wechatObj->xml2Array($xmlstring)["xml"];
    
    if($accept_info){
        $ToUserName = $accept_info["ToUserName"];
        $FromUserName = $accept_info["FromUserName"];
        $CreateTime = $accept_info["CreateTime"];
        $MsgType = $accept_info["MsgType"];
        //$MsgId = $accept_info["MsgId"];
        // $Encrypt = $accept_info["Encrypt"];
        
        $data = array();
        if($MsgType == "text"){//接收文本
            
            $Content = $accept_info["Content"];//文本内容
    
            // "touser": "OPENID",
            // "msgtype": "link",
            // "link": {
            //       "title": "Happy Day",
            //       "description": "Is Really A Happy Day",
            //       "url": "URL",
            //       "thumb_url": "THUMB_URL"
            // }
            if($Content === "图文") {
                $data["touser"] = $FromUserName;
                $data["msgtype"] = "link";
                $data["link"]["title"] = urlencode("文章标题");
                $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";
                $wechatObj->send($data);exit;
            }
            //else if 可以做好多事
            
        }else if($MsgType === "image") {//接收图片

        }else if($MsgType === "event") {//进入客服窗口事件
            $Event = $accept_info["Event"];
            $SessionFrom = $accept_info["SessionFrom"];
            if($Event == "user_enter_tempsession") {
                $data["touser"] = $FromUserName;
                $data["msgtype"] = "text";
                $data["text"]["content"] = urlencode("您好很高兴为您服务");//urlencode 解决中文乱码问题
                $wechatObj->send($data);exit;
            }
        }
        
        echo "".$CreateTime."";
    }

}