feat: add user balance

backend/app/http/posts.go

@@ -293,6 +293,12 @@ func (ctl *posts) Buy(ctx fiber.Ctx, id int64, user *model.Users) (*wechat.JSAPI
 		return &wechat.JSAPIPayParams{
 			AppId: "balance",
 		}, nil
+	} else {
+		payPrice = payPrice - user.Balance
+		err = models.Users.SetBalance(ctx.Context(), user.ID, 0)
+		if err != nil {
+			return nil, errors.Wrap(err, "余额支付失败")
+		}
 	}
 
 	prePayResp, err := ctl.wepay.V3TransactionJsapi(ctx.Context(), func(bm *wepay.BodyMap) {

backend/app/http/users.go

@@ -18,6 +18,7 @@ type UserInfo struct {
 	CreatedAt time.Time `json:"created_at,omitempty"`
 	Username  string    `json:"username,omitempty"`
 	Avatar    string    `json:"avatar,omitempty"`
+	Balance   int64     `json:"balance,omitempty"`
 }
 
 // @Router	/users/profile [get]
@@ -28,6 +29,7 @@ func (ctl *users) Profile(ctx fiber.Ctx, user *model.Users) (*UserInfo, error) {
 		CreatedAt: user.CreatedAt,
 		Username:  user.Username,
 		Avatar:    *user.Avatar,
+		Balance:   user.Balance,
 	}, nil
 }