PHP实现微信公众号分享接口

  <?php

class ShareModel extends BaseModel
{
    var $appId = APPID;
    var $appSecret = APPSECRET;

    public function getJsApiTicket()
    {
        $ticket_file = '/dev/shm/jsapi_ticket.json';
        $data = json_decode(file_get_contents($ticket_file));
        if ($data->expire_time < time()) {
            $accessToken = $this->getApiAccessToken();
            $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=$accessToken";
            $res = json_decode($this->http_request($url));
            $ticket = $res->ticket;
            if ($ticket) {
                $data->expire_time = time() + 7000;
                $data->jsapi_ticket = $ticket;
                file_put_contents($ticket_file, json_encode($data));
            }
        } else {
            $ticket = $data->jsapi_ticket;
        }

        return $ticket;
    }

/*微信公众号，不需要获取用户信息：所以不需要授权，即使用appid、appsecret和grant_type换取access_token*/
/*
微信对于access_token的请求存在日请求数的限制 所以要全局缓存access_token,在过期时间内直接使用存的值；
这里使用file_put_contents()代替fwrite()、fopen()、fclose()；
 file_put_content()如果文件不存在就先创建文件这里要注意把缓存文件放/dev/shm/*下面，这个磁盘文件会在重启的时候清空数据，
由于这个access_token丢失也不会存在问题，所以存在这里有助于减轻磁盘内存压力
*/
    
    private function getApiAccessToken()
    {
        $token_file = '/dev/shm/access_token.json';
        $data = json_decode(file_get_contents($token_file));
        if ($data->expire_time < time()) {
            $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=$this->appId&secret=$this->appSecret";
            $res = json_decode($this->http_request($url));
            $access_token = $res->access_token;
            if ($access_token) {
                $data->expire_time = time() + 7000;
                $data->access_token = $access_token;
                file_put_contents($token_file, json_encode($data));
            }
        } else {
            $access_token = $data->access_token;
        }
        return $access_token;
    }


    //HTTP请求（支持HTTP/HTTPS，支持GET/POST）
    private function http_request($url, $data = null)
    {
        $curl = curl_init();
        curl_setopt($curl, CURLOPT_URL, $url);
        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, FALSE);
        curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, FALSE);
        if (!empty($data)) {
            curl_setopt($curl, CURLOPT_POST, TRUE);
            curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
        }
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, TRUE);
        $output = curl_exec($curl);
        curl_close($curl);
        file_put_contents('/tmp/weixin.' . date("Ymd") . '.log', date("Y-m-d H:i:s") . "\t" . $output . "\n", FILE_APPEND); //记录微信请求的相关日志，以用于排插错误
        return $output;
    }

|调用方式：
接收前端传过来的当前请求页的url

    public function getApiTicketAction()
    {
        $model = new ShareModel();
        $jsapiTicket = $model->getJsApiTicket();
        $url = $this->_req->getQuery('url',"");
        if(!$url){
            response::err_lack_param(); //做一个参数检测的判断
        }
        $timestamp = time();
        $nonceStr = $this->createNonceStr(); //构造一个随机数，用来生成签名的一部分

        $string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr&timestamp=$timestamp&url=$url"; //签名算法先按照ascII码排序
        $signature = sha1($string);  //对排序好的字符串加密
        $signPackage = array(
            "appId"     => $model->appId,
            "nonceStr"  => $nonceStr,
            "timestamp" => $timestamp,
            "signature" => $signature,
        );
        response::result($signPackage); //返回数据给前端
    }

    private function createNonceStr($length = 16) { //生成随机16个字符的字符串
        $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
        $str = "";
        for ($i = 0; $i < $length; $i++) {
            $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        }
        return $str;
    }