详细记录PHP微信小程序中微信支付v3的应用

//统一下单

public function wechartAddOrder($name,$ordernumber,$money,$openid){

        $url = "https://api.mch.weixin.qq.com/v3/pay/transactions/jsapi";

        $urlarr = parse_url($url);

        $appid = config('config.appId');//appID

        $mchid = config('config.mchid');//商户ID

        $xlid = config('config.apiXL');//API序列号

        $data = array();

        $randstr = getRanStr(16,false);//随机字符串长度不超过32

        $time = time();

        $data['appid'] = $appid;

        $data['mchid'] = $mchid;

        $data['description'] = $name;//商品描述

        $data['out_trade_no'] = $ordernumber;//订单编号

        $data['notify_url'] = "https://www.xffly-/api/admin/order/wechartCallback";//回调接口

//      $data['amount']['total'] = $money;//金额

        $data['amount']['total'] = 1;

        $data['payer']['openid'] = $openid;//用户openID

        $data = json_encode($data); 

        $key = $this->getSign($data,$urlarr['path'],$randstr,$time);//签名

        $token = sprintf('mchid="%s",serial_no="%s",nonce_str="%s",timestamp="%d",signature="%s"',$mchid,$xlid,$randstr,$time,$key);//头部信息

        $header  = array(

            'Content-Type:'.'application/json; charset=UTF-8',

            'Accept:application/json',

            'User-Agent:*/*',

            'Authorization: WECHATPAY2-SHA256-RSA2048 '.$token

        );  

        $ret = curl_post_https($url,$data,$header);

        return $ret;

    }

//微信支付签名

public function getSign($data=array(),$url,$randstr,$time){

        $str = "POST"."\n".$url."\n".$time."\n".$randstr."\n".$data."\n";

        $key = file_get_contents('apiclient_key.pem');//在商户平台-的秘钥

        $str = getSha256WithRSA($str,$key);

        return $str;

    }

//调起支付的签名

public function getWechartSign($post){

        $data = array();

        $data['timeStamp'] = $post['timeStamp'];

        $data['nonceStr'] = $post['str'];

        $data['package'] = $post['package'];

        $str = config('config.appId')."\n".$data['timeStamp']."\n".$data['nonceStr']."\n".$data['package']."\n";

        $key = file_get_contents('apiclient_key.pem');

        $str = getSha256WithRSA($str,$key);

        return $str;

    }

//微信回调写入日志文件并返回

    public function writeWechartLog($post){

        if(!is_dir("upload/log")){

           mkdir("upload/log",0777,true);

        }

        $log = fopen("upload/log/wechart.txt", "a+");

        if(is_array($post)){

            $post = json_encode($post);

        }

        fwrite($log, $post."\n");

        fclose($log);

        $read = fopen("upload/log/wechart.txt", "r");

        fseek($read, -1, SEEK_END);

        $s = '';

        while (($c = fgetc($read)) !== false) {

            if ($c == "\n" && $s) break;

            $s = $c . $s;

            fseek($read, -2, SEEK_CUR);

        }

        fclose($read);

        return $s;//取刚刚存的最后一条回调信息

    }

//微信回调解密

    public function wechartDecrypt($str) {

        $str = htmlspecialchars_decode($str,ENT_COMPAT);

        $post = json_decode($str,true);

        $key = config("config.apiv3Key");//商户平台设置的api v3 密码

        $text = base64_decode($post['resource']['ciphertext']);

        $str = sodium_crypto_aead_aes256gcm_decrypt($text,$post['resource']['associated_data'],$post['resource']['nonce'],$key);

        return json_decode($str,true);

    }