Move code to pkg

pkg/middlewares/handler_switcher.go

@@ -0,0 +1,35 @@
+package middlewares
+
+import (
+	"net/http"
+
+	"github.com/containous/traefik/pkg/safe"
+)
+
+// HTTPHandlerSwitcher allows hot switching of http.ServeMux
+type HTTPHandlerSwitcher struct {
+	handler *safe.Safe
+}
+
+// NewHandlerSwitcher builds a new instance of HTTPHandlerSwitcher
+func NewHandlerSwitcher(newHandler http.Handler) (hs *HTTPHandlerSwitcher) {
+	return &HTTPHandlerSwitcher{
+		handler: safe.New(newHandler),
+	}
+}
+
+func (h *HTTPHandlerSwitcher) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
+	handlerBackup := h.handler.Get().(http.Handler)
+	handlerBackup.ServeHTTP(rw, req)
+}
+
+// GetHandler returns the current http.ServeMux
+func (h *HTTPHandlerSwitcher) GetHandler() (newHandler http.Handler) {
+	handler := h.handler.Get().(http.Handler)
+	return handler
+}
+
+// UpdateHandler safely updates the current http.ServeMux with a new one
+func (h *HTTPHandlerSwitcher) UpdateHandler(newHandler http.Handler) {
+	h.handler.Set(newHandler)
+}