七月迭代短暂完结,还有很多后端的关键东西没有弄,这是一版赶时间做的东西

internal/service/paymentmethod/policy.go

@@ -0,0 +1,134 @@
+// Package paymentmethod 提供按资产类型读取和校验 C 端支付方式的能力。
+package paymentmethod
+
+import (
+	"context"
+	stderrors "errors"
+	"slices"
+
+	"github.com/break/junhong_cmp_fiber/internal/model"
+	"github.com/break/junhong_cmp_fiber/pkg/constants"
+	"github.com/break/junhong_cmp_fiber/pkg/errors"
+	"github.com/bytedance/sonic"
+)
+
+// ConfigReader 提供受控系统配置读取能力。
+type ConfigReader interface {
+	GetStrict(ctx context.Context, key string) (string, error)
+}
+
+// Policy 负责返回资产允许的支付方式并执行后端强校验。
+type Policy struct {
+	reader ConfigReader
+}
+
+// NewPolicy 创建支付方式策略。
+func NewPolicy(reader ConfigReader) *Policy {
+	return &Policy{reader: reader}
+}
+
+// AllowedMethods 返回指定资产类型允许的支付方式；配置异常时失败关闭。
+func (p *Policy) AllowedMethods(ctx context.Context, assetType string) ([]string, error) {
+	if p == nil || p.reader == nil {
+		return nil, errors.New(errors.CodeNoPaymentConfig)
+	}
+	key, err := configKey(assetType)
+	if err != nil {
+		return nil, err
+	}
+	raw, err := p.reader.GetStrict(ctx, key)
+	if err != nil {
+		return nil, errors.Wrap(errors.CodeNoPaymentConfig, err, "读取支付方式配置失败")
+	}
+	var methods []string
+	if err := sonic.Unmarshal([]byte(raw), &methods); err != nil || !validMethods(methods) {
+		return nil, errors.New(errors.CodeNoPaymentConfig, "支付方式配置无效")
+	}
+	return stableMethods(methods), nil
+}
+
+// EnsureAllowed 校验指定支付方式是否允许。
+func (p *Policy) EnsureAllowed(ctx context.Context, assetType, paymentMethod string) error {
+	methods, err := p.AllowedMethods(ctx, assetType)
+	if err != nil {
+		return err
+	}
+	if !slices.Contains(methods, paymentMethod) {
+		return errors.New(errors.CodePaymentMethodUnavailable)
+	}
+	return nil
+}
+
+// AllowedRechargeMethods 返回资产允许且钱包充值接口支持的第三方支付方式。
+func (p *Policy) AllowedRechargeMethods(ctx context.Context, assetType string) ([]string, error) {
+	methods, err := p.AllowedMethods(ctx, assetType)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]string, 0, 2)
+	for _, method := range methods {
+		if method == model.PaymentMethodWechat || method == model.PaymentMethodAlipay {
+			result = append(result, method)
+		}
+	}
+	return result, nil
+}
+
+// EnsureRechargeAllowed 校验普通充值只使用资产配置允许的第三方支付方式。
+func (p *Policy) EnsureRechargeAllowed(ctx context.Context, assetType, paymentMethod string) error {
+	methods, err := p.AllowedRechargeMethods(ctx, assetType)
+	if err != nil {
+		return err
+	}
+	if !slices.Contains(methods, paymentMethod) {
+		return errors.New(errors.CodePaymentMethodUnavailable)
+	}
+	return nil
+}
+
+func configKey(assetType string) (string, error) {
+	switch assetType {
+	case "card", constants.AssetTypeIotCard, model.OrderTypeSingleCard:
+		return constants.SystemConfigPaymentAllowedCard, nil
+	case constants.AssetTypeDevice:
+		return constants.SystemConfigPaymentAllowedDevice, nil
+	default:
+		return "", errors.New(errors.CodeInvalidParam, "无效的资产类型")
+	}
+}
+
+func validMethods(methods []string) bool {
+	if len(methods) == 0 {
+		return false
+	}
+	seen := make(map[string]struct{}, len(methods))
+	for _, method := range methods {
+		if method != model.PaymentMethodWallet && method != model.PaymentMethodWechat && method != model.PaymentMethodAlipay {
+			return false
+		}
+		if _, exists := seen[method]; exists {
+			return false
+		}
+		seen[method] = struct{}{}
+	}
+	return true
+}
+
+// ValidateConfigValue 校验支付方式系统配置的 JSON 集合。
+func ValidateConfigValue(value string) error {
+	var methods []string
+	if err := sonic.Unmarshal([]byte(value), &methods); err != nil || !validMethods(methods) {
+		return stderrors.New("支付方式配置必须是非空且不重复的合法数组")
+	}
+	return nil
+}
+
+func stableMethods(methods []string) []string {
+	result := make([]string, 0, len(methods))
+	for _, method := range []string{model.PaymentMethodWallet, model.PaymentMethodWechat, model.PaymentMethodAlipay} {
+		if slices.Contains(methods, method) {
+			result = append(result, method)
+		}
+	}
+	return result
+}