course/app/common/service/PayService.php

<?php

namespace app\common\service;

use app\common\service\Channel\wechat\WechatConstants;
use app\constant\ResponseCode;
use GuzzleHttp\Exception\RequestException;
use think\Exception;
use WeChatPay\Builder;
use WeChatPay\Crypto\Rsa;
use WeChatPay\Formatter;
use WeChatPay\Util\PemUtil;

class PayService
{
    protected $config;
    protected $instance;
    protected $platformPublicKeyInstance;
    protected $merchantPrivateKeyInstance;

    public function __construct()
    {
        // 服务商 商户号
        $merchantId = getenv('MERCHANT_ID');
        // 从本地文件中加载「商户API私钥」，「商户API私钥」会用来生成请求的签名
        $merchantPrivateKeyFilePath = 'file://' . base_path()  . '/certificate/apiclient_key.pem';

        $this->merchantPrivateKeyInstance = Rsa::from($merchantPrivateKeyFilePath, Rsa::KEY_TYPE_PRIVATE);

        // 「商户API证书」的「证书序列号」
        $merchantCertificateSerial = '3297EB3A1132A39DAFFD70A6C4A6C3078CD346F7';

        // 从本地文件中加载「微信支付平台证书」，用来验证微信支付应答的签名
        $platformCertificateFilePath = 'file://' . base_path()  . '/certificate/wechatpay_660FAD2D6E804E37BE9D77EF5882718CC1E3399F.pem';
        $this->platformPublicKeyInstance = Rsa::from($platformCertificateFilePath, Rsa::KEY_TYPE_PUBLIC);

        // 从「微信支付平台证书」中获取「证书序列号」
        $platformCertificateSerial = PemUtil::parseCertificateSerialNo($platformCertificateFilePath);

        // 构造一个 APIv3 客户端实例
        $this->instance = Builder::factory([
            'mchid'      => $merchantId,
            'serial'     => $merchantCertificateSerial,
            'privateKey' => $this->merchantPrivateKeyInstance,
            'certs'      => [
                $platformCertificateSerial => $this->platformPublicKeyInstance,
            ],
        ]);


    }

    /**
     * @desc jsapi支付
     * @param array $pay_data
     * @param $seller_channel
     * @return array
     */
    public function payment(array $pay_data)
    {
        try {

            $request_data = [
                'appid' => getenv('APP_ID'),// 公众号ID
                'mchid' => getenv('MERCHANT_ID'),//直连商户号
                'description' => $pay_data['desc'],//商品描述
                'out_trade_no' => $pay_data['out_trade_no'],//商户订单号
                'notify_url' => $pay_data['notify_url'],//通知地址
                'amount' => [
                    'total' => round($pay_data['total_amount'] * 100),//总金额 单位为分
                ],
                'payer' => [
                    'openid' => $pay_data['openid'],// 用户在服务商AppID下的唯一标识
                ]
            ];

            $resp = $this->instance
                ->chain('/v3/pay/transactions/jsapi')
                ->post([
                    'json' => $request_data,
//                    'debug' => true
                ]);

            $result = json_decode($resp->getBody(), true);

            raw_log('wechat_pay/transactions_jsapi', ['request_data' => $request_data, 'result' => $result]);

            $pay_data = [
                'appId' => getenv('APP_ID'),  //微信小程序appid
                'timeStamp' => strval(Formatter::timestamp()),
                'nonceStr' => Formatter::nonce(),
                'package' => 'prepay_id=' . $result['prepay_id'],
            ];
            $pay_data['paySign'] = Rsa::sign(
                Formatter::joinedByLineFeed(...array_values($pay_data)),
                $this->merchantPrivateKeyInstance
            );
            $pay_data['signType'] = 'RSA';

            return $pay_data;
        } catch (RequestException $exception) {
            $response = $exception->getResponse();
            $result = json_decode($response->getBody()->getContents(), true);

            raw_log('wechat_pay/transactions_jsapi_failed', ['pay_data' => $pay_data, 'result' => $result]);
            return [
                'code' => ResponseCode::FAIL,
                'msg' => $result['message']
            ];
        }
    }


    /**
     * @desc 退款
     * @param $refund_data
     * @return array
     */
    public function refundPayment($refund_data)
    {
        try {
            //退款数据
            $request_data = [
                'out_trade_no' => $refund_data['out_trade_no'],//微信支付订单号
                'out_refund_no' => $refund_data['out_refund_no'],//商户退款单号
                'reason' => $refund_data['refund_desc'],//退款原因
                'notify_url' => $refund_data['notify_url'],//通知地址
                'amount' => [
                    'refund' => round($refund_data['refund_amount'] * 100),//退款金额
                    'total' => round($refund_data['total'] * 100),//原订单金额
                    'currency' => 'CNY',//退款币种
                ]
            ];
            $resp = $this->instance
                ->chain('/v3/refund/domestic/refunds')
                ->post([
                    'json' => $request_data,
//                    'debug' => true
                ]);

            $result = json_decode($resp->getBody(), true);
            raw_log('wechat_pay/refund', ['request_data' => $request_data, 'result' => $result]);

            return [
                'transaction_id' => $result['transaction_id'],
                'out_transaction_id' => $result['refund_id'],
                'out_trade_no' => $result['out_refund_no'],
            ];

        } catch (RequestException $exception) {
            $response = $exception->getResponse();
            $result = json_decode($response->getBody()->getContents(), true);
            raw_log('wechat_pay/refund_failed', ['request_data' => $request_data, 'result' => $result]);

            return [
                'code' => ResponseCode::FAIL,
                'msg' => $result['message']
            ];
        }
    }


    /**
     * @desc 余额查询  微信没有余额查询接口，返回假数据
     * @param $seller_channel
     * @return array
     */
    public function queryBalanceAmount($seller_channel)
    {
        return [
            'code'=>ResponseCode::SUCCESS,
            'data'=>[
                'total_amount'=>0.00,
                'settled_amount'=>0.00,
                'not_settled_amount'=>0.00
            ]
        ];
    }

}