remove json packages in app folder

app/router/config_cache.go

@@ -0,0 +1,31 @@
+package router
+
+import (
+	"errors"
+)
+
+type ConfigObjectCreator func([]byte) (interface{}, error)
+
+var (
+	configCache map[string]ConfigObjectCreator
+
+	ErrorRouterNotFound = errors.New("Router not found.")
+)
+
+func RegisterRouterConfig(strategy string, creator ConfigObjectCreator) error {
+	// TODO: check strategy
+	configCache[strategy] = creator
+	return nil
+}
+
+func CreateRouterConfig(strategy string, data []byte) (interface{}, error) {
+	creator, found := configCache[strategy]
+	if !found {
+		return nil, ErrorRouterNotFound
+	}
+	return creator(data)
+}
+
+func init() {
+	configCache = make(map[string]ConfigObjectCreator)
+}