微信开发SDK

文档：
1.微信根据code获取access_token;
2.微信自身获取access_token和openid;
3.根据access_token和openid获取用户信息；
4.微信分享获取的数据包；（主要是签名算法）

<?php

namespace app\common\lib\wx;

use app\common\lib\Redis;
use app\common\lib\Show;
use Curl\Curl;

class WX
{
    protected $appid;
    protected $appsecret;

    public  $Curl;
    public $Redis;

    public function __construct()
    {
        $this->appid = config('wx.AppID');
        $this->appsecret = config('wx.AppSecret');
        $this->Curl = new Curl();
        $this->Redis = new Redis();
    }



    /**
     * 根据code获取accesstoken和openid
     * @param $code
     * @return mixed
     * @throws \Exception
     */
    public  function getAccessToken($code)
    {
        $data = array(
          'appid'=>$this->appid,
          'appsecret'=>$this->appsecret,
          'grant_type'=>'authorization_code',
          'code' => $code
        );
        $url = " https://api.weixin.qq.com/sns/oauth2/access_token";
        $res = $this->Curl->get($url,$data);
        $res = json_decode($res,true);
        if ($res['errcode'])
        {
            throw new \Exception($res['errmsg']);
        }
        return $res;
    }


    /**
     * 根据openid和access_token获取用户信息
     * @param $accessToken
     * @param $openid
     * @return mixed
     * @throws \Exception
     */
    public function getInfoByAccessToken($accessToken,$openid)
    {
        $data = array(
            'access_token'=>$accessToken,
            'openid'=>$openid,
            'lang'=>'zh_CN',
        );
        $url = " https://api.weixin.qq.com/sns/userinfo";
        $res = $this->Curl->get($url,$data);
        $res = json_decode($res,true);
        if ($res['errcode'])
        {
            throw new \Exception($res['errmsg']);
        }
        return $res;
    }

    /**
     * 设置noncestr（随机字符串）
     * @param int $length
     * @return string
     */
    public function createNonceStr($length = 16) {
        $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
        $str = "";
        for ($i = 0; $i < $length; $i++) {
            $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        }
        return $str;
    }

    /**
     * 获取access_token，有效期7200秒
     * @param $access_token
     * @return bool|string|\think\response\Json
     */
    public function  getSelfAccessToken()
    {
        $access_token = $this->Redis->get("access_token");
        if (!$access_token) {
            $access_token_url  = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=" . config('wx.AppID') . "&secret=" . config("wx.AppSecret");
            $access_token_data = json_decode($this->Curl->get($access_token_url),true);
            if ($access_token_data['errcode'] || !$access_token_data) {
                return Show::error("未获取access_token");
            }
            $access_token = $access_token_data['access_token'];
            $this->Redis->set("access_token",$access_token,"7000");
        }
        return  $access_token;
    }

    /**
     * 获得jsapi_ticket，有效期7200秒
     * @param $access_token
     * @return bool|string|\think\response\Json
     */
    public function  getJsApiTicket($access_token)
    {
        $jsapi_ticket = $this->Redis->get("jsapi_ticket");
        if (!$jsapi_ticket){
            $jsapi_ticket_url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token=".$access_token."&type=jsapi";
            $jsapi_ticket_data = json_decode($this->Curl->get($jsapi_ticket_url),true);
            if ($jsapi_ticket_data['errcode'] !=0){
                return Show::error("未获取jsapi_ticket");
            }
            $jsapi_ticket = $jsapi_ticket_data['ticket'];
            $this->Redis->set("jsapi_ticket",$jsapi_ticket,"7000");
        }
        return $jsapi_ticket;
    }

    /**
     * 签名算法
     * @return array
     */
    public function getSignPackage()
    {
        //获取access_token，有效期7200秒
        $access_token = $this->getSelfAccessToken();
        //获得jsapi_ticket，有效期7200秒
        $jsapiTicket = $this->getJsApiTicket($access_token);
        $nonceStr = $this->createNonceStr();
        // 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();
        // 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;


    }

}