www.x-motion.cn/ThinkPHP/Library/Org/Util/Jssdk.class.php

<?php
namespace Org\Util;

use Common\Cache\RedisCache;
/*
 * 微信jssdk
 */
class Jssdk {
  private $appId;
  private $appSecret;

  public function __construct($appId, $appSecret) {
    $this->appId = $appId;
    $this->appSecret = $appSecret;
  }

  public function getSignPackage($url) {
    $jsapiTicket = $this->getJsApiTicket();

    // 注意 URL 一定要动态获取，不能 hardcode.
    //$protocol = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off' || $_SERVER['SERVER_PORT'] == 443) ? "https://" : "http://";
    //$url = "$protocol$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";

    $timestamp = time();
    $nonceStr = $this->createNonceStr();

    // 这里参数的顺序要按照 key 值 ASCII 码升序排序
    $string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr&timestamp=$timestamp&url=$url";

    $signature = sha1($string);

    $signPackage = array(
        "appId"     => $this->appId,
        "nonceStr"  => $nonceStr,
        "timestamp" => $timestamp,
        "url"       => $url,
        "signature" => $signature,
        "rawString" => $string
    );
    return $signPackage;
  }

  private function createNonceStr($length = 16) {
    $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
    $str = "";
    for ($i = 0; $i < $length; $i++) {
      $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
    }
    return $str;
  }

  private function getJsApiTicket() {
    $authname = 'wechat_jsapi_ticket'.$this->appId;
    if ($ticket = $this->getCache($authname))  {
      return $ticket;
    }
    $accessToken = $this->getAccessToken();
    $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=$accessToken";
    $result = $this->httpGet($url);
    if ($result) {
      $json = json_decode($result,true);
      if (!$json || !empty($json['errcode'])) {
        $this->errCode = $json['errcode'];
        $this->errMsg = $json['errmsg'];
        return false;
      }
      $ticket = $json['ticket'];
      $expire = $json['expires_in'] ? intval($json['expires_in'])-100 : 3600;
      $this->setCache($authname,$ticket,$expire);
      return $ticket;
    }
  }

  private function getAccessToken() {
    $authname = 'wechat_access_token'.$this->appId;
    if ($access_token = $this->getCache($authname))  {
        return $access_token;
    }
    $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=$this->appId&secret=$this->appSecret";
    $result = $this->httpGet($url);
    if ($result) {
        $json = json_decode($result,true);
        if (!$json || isset($json['errcode'])) {
          $this->errCode = $json['errcode'];
          $this->errMsg = $json['errmsg'];
          return false;
        }
        $access_token = $json['access_token'];
        $expire = $json['expires_in'] ? intval($json['expires_in'])-100 : 3600;
        $this->setCache($authname,$access_token,$expire);
        return $access_token;
    }
  }

  private function httpGet($url) {
    $curl = curl_init();
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($curl, CURLOPT_TIMEOUT, 500);
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, true);
    curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, true);
    curl_setopt($curl, CURLOPT_URL, $url);

    $res = curl_exec($curl);
    curl_close($curl);

    return $res;
  }

  /**
   * 设置缓存
   * @param string $cachename
   * @param mixed $value
   * @param int $expired
   * @return boolean
   */
  private function setCache($cachename,$value,$expired){
    $redis_cache = new RedisCache();
    $redis_cache->set($cachename,$value,$expired);
  }

  /**
   * 获取缓存
   * @param string $cachename
   * @return mixed
   */
  private function getCache($cachename){
    $redis_cache = new RedisCache();
    return $redis_cache->get($cachename);
  }
}