feat: 004/phase 1

internal/proxy/forwarder.go

@@ -0,0 +1,68 @@
+package proxy
+
+import (
+	"strings"
+	"sync"
+
+	"github.com/gofiber/fiber/v3"
+
+	"github.com/any-hub/any-hub/internal/server"
+)
+
+// Forwarder 根据 HubRoute 的 module_key 选择对应的 ProxyHandler，默认回退到构造时注入的 handler。
+type Forwarder struct {
+	defaultHandler server.ProxyHandler
+}
+
+// NewForwarder 创建 Forwarder，defaultHandler 不能为空。
+func NewForwarder(defaultHandler server.ProxyHandler) *Forwarder {
+	return &Forwarder{defaultHandler: defaultHandler}
+}
+
+var (
+	moduleHandlers sync.Map
+)
+
+// RegisterModuleHandler 将特定 module_key 映射到 ProxyHandler，重复注册会覆盖旧值。
+func RegisterModuleHandler(key string, handler server.ProxyHandler) {
+	normalized := normalizeModuleKey(key)
+	if normalized == "" || handler == nil {
+		return
+	}
+	moduleHandlers.Store(normalized, handler)
+}
+
+// Handle 实现 server.ProxyHandler，根据 route.ModuleKey 选择 handler。
+func (f *Forwarder) Handle(c fiber.Ctx, route *server.HubRoute) error {
+	handler := f.lookup(route)
+	if handler == nil {
+		return fiber.NewError(fiber.StatusInternalServerError, "proxy handler unavailable")
+	}
+	return handler.Handle(c, route)
+}
+
+func (f *Forwarder) lookup(route *server.HubRoute) server.ProxyHandler {
+	if route != nil {
+		if handler := lookupModuleHandler(route.ModuleKey); handler != nil {
+			return handler
+		}
+	}
+	return f.defaultHandler
+}
+
+func lookupModuleHandler(key string) server.ProxyHandler {
+	normalized := normalizeModuleKey(key)
+	if normalized == "" {
+		return nil
+	}
+	if value, ok := moduleHandlers.Load(normalized); ok {
+		if handler, ok := value.(server.ProxyHandler); ok {
+			return handler
+		}
+	}
+	return nil
+}
+
+func normalizeModuleKey(key string) string {
+	return strings.ToLower(strings.TrimSpace(key))
+}