Dynamic Configuration Refactoring

old/middlewares/replace_path.go

@@ -0,0 +1,28 @@
+package middlewares
+
+import (
+	"context"
+	"net/http"
+)
+
+const (
+	// ReplacePathKey is the key within the request context used to
+	// store the replaced path
+	ReplacePathKey key = "ReplacePath"
+	// ReplacedPathHeader is the default header to set the old path to
+	ReplacedPathHeader = "X-Replaced-Path"
+)
+
+// ReplacePath is a middleware used to replace the path of a URL request
+type ReplacePath struct {
+	Handler http.Handler
+	Path    string
+}
+
+func (s *ReplacePath) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	r = r.WithContext(context.WithValue(r.Context(), ReplacePathKey, r.URL.Path))
+	r.Header.Add(ReplacedPathHeader, r.URL.Path)
+	r.URL.Path = s.Path
+	r.RequestURI = r.URL.RequestURI()
+	s.Handler.ServeHTTP(w, r)
+}