smart_canteen/app/svc/svc_wx_pay.go

package svc

import (
	"applet/app/db"
	"applet/app/enum"
	"github.com/gin-gonic/gin"
	"github.com/wechatpay-apiv3/wechatpay-go/core"
	"github.com/wechatpay-apiv3/wechatpay-go/core/option"
	"github.com/wechatpay-apiv3/wechatpay-go/utils"
)

func NewWxPayClient(ctx *gin.Context) (client *core.Client, err error) {
	sysCfgDb := db.SysCfgDb{}
	sysCfgDb.Set()
	sysCfg := sysCfgDb.SysCfgFindWithDb(enum.WxMchId, enum.WxMchApiV3Key, enum.WxMchCertificateSerialNumber)

	var (
		mchID                      string = sysCfg[enum.WxMchId]                      // 商户号
		mchCertificateSerialNumber string = sysCfg[enum.WxMchCertificateSerialNumber] // 商户证书序列号
		mchAPIv3Key                string = sysCfg[enum.WxMchApiV3Key]                // 商户APIv3密钥
	)

	// 使用 utils 提供的函数从本地文件中加载商户私钥，商户私钥会用来生成请求的签名
	mchPrivateKey, err := utils.LoadPrivateKeyWithPath("./static/wx/merchant/apiclient_key.pem")
	if err != nil {
		return
	}

	// 使用商户私钥等初始化 client，并使它具有自动定时获取微信支付平台证书的能力
	opts := []core.ClientOption{
		option.WithWechatPayAutoAuthCipher(mchID, mchCertificateSerialNumber, mchPrivateKey, mchAPIv3Key),
	}
	client, err = core.NewClient(ctx, opts...)
	if err != nil {
		return
	}
	return
}