From f670cc465211fb5328ee2beae330a6625750471c Mon Sep 17 00:00:00 2001
From: Clayton Coleman <ccoleman@redhat.com>
Date: Sat, 21 May 2016 00:05:39 -0400
Subject: [PATCH] Avoid multiple allocations during selfLink generation

---
 pkg/apiserver/api_installer.go      | 21 ++++++++++++++-------
 pkg/apiserver/api_installer_test.go |  4 +++-
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/pkg/apiserver/api_installer.go b/pkg/apiserver/api_installer.go
index 423f09bfc4e..4a27a2ee126 100644
--- a/pkg/apiserver/api_installer.go
+++ b/pkg/apiserver/api_installer.go
@@ -390,18 +390,26 @@ func (a *APIInstaller) registerResourceHandlers(path string, storage rest.Storag
 
 		resourcePath := namespacedPath
 		resourceParams := namespaceParams
+		itemPathPrefix := gpath.Join(a.prefix, scope.ParamName()) + "/"
 		itemPath := namespacedPath + "/{name}"
+		itemPathMiddle := "/" + resource + "/"
 		nameParams := append(namespaceParams, nameParam)
 		proxyParams := append(nameParams, pathParam)
+		itemPathSuffix := ""
 		if hasSubresource {
-			itemPath = itemPath + "/" + subresource
+			itemPathSuffix = "/" + subresource
+			itemPath = itemPath + itemPathSuffix
 			resourcePath = itemPath
 			resourceParams = nameParams
 		}
 		apiResource.Name = path
 		apiResource.Namespaced = true
 		apiResource.Kind = resourceKind
-		namer := scopeNaming{scope, a.group.Linker, gpath.Join(a.prefix, itemPath), false}
+
+		itemPathFn := func(name, namespace string) string {
+			return itemPathPrefix + namespace + itemPathMiddle + name + itemPathSuffix
+		}
+		namer := scopeNaming{scope, a.group.Linker, itemPathFn, false}
 
 		actions = appendIf(actions, action{"LIST", resourcePath, resourceParams, namer}, isLister)
 		actions = appendIf(actions, action{"POST", resourcePath, resourceParams, namer}, isCreater)
@@ -430,7 +438,7 @@ func (a *APIInstaller) registerResourceHandlers(path string, storage rest.Storag
 		// For ex: LIST all pods in all namespaces by sending a LIST request at /api/apiVersion/pods.
 		// TODO: more strongly type whether a resource allows these actions on "all namespaces" (bulk delete)
 		if !hasSubresource {
-			namer = scopeNaming{scope, a.group.Linker, gpath.Join(a.prefix, itemPath), true}
+			namer = scopeNaming{scope, a.group.Linker, itemPathFn, true}
 			actions = appendIf(actions, action{"LIST", resource, params, namer}, isLister)
 			actions = appendIf(actions, action{"WATCHLIST", "watch/" + resource, params, namer}, allowWatchList)
 		}
@@ -775,7 +783,7 @@ func (n rootScopeNaming) ObjectName(obj runtime.Object) (namespace, name string,
 type scopeNaming struct {
 	scope meta.RESTScope
 	runtime.SelfLinker
-	itemPath      string
+	itemPathFn    func(name, namespace string) string
 	allNamespaces bool
 }
 
@@ -822,9 +830,8 @@ func (n scopeNaming) GenerateLink(req *restful.Request, obj runtime.Object) (pat
 	if len(name) == 0 {
 		return "", "", errEmptyName
 	}
-	path = strings.Replace(n.itemPath, "{name}", name, 1)
-	path = strings.Replace(path, "{"+n.scope.ArgumentName()+"}", namespace, 1)
-	return path, "", nil
+
+	return n.itemPathFn(name, namespace), "", nil
 }
 
 // GenerateListLink returns the appropriate path and query to locate a list by its canonical path.
diff --git a/pkg/apiserver/api_installer_test.go b/pkg/apiserver/api_installer_test.go
index 57df10e94c4..3d5f2b869a4 100644
--- a/pkg/apiserver/api_installer_test.go
+++ b/pkg/apiserver/api_installer_test.go
@@ -36,7 +36,9 @@ func TestScopeNamingGenerateLink(t *testing.T) {
 	s := scopeNaming{
 		meta.RESTScopeNamespace,
 		selfLinker,
-		"/api/v1/namespaces/{namespace}/services/{name}",
+		func(name, namespace string) string {
+			return "/api/v1/namespaces/" + namespace + "/services/" + name
+		},
 		true,
 	}
 	service := &api.Service{