From 3d1e8a92d3a4d403cea39ffd0640a94f5430eb20 Mon Sep 17 00:00:00 2001
From: Daniel Smith <dbsmith@google.com>
Date: Fri, 27 Jun 2014 17:04:11 -0700
Subject: [PATCH] Move stringSet to util.StringSet

---
 pkg/registry/minion_registry.go | 29 ++++++------------------
 pkg/util/set.go                 | 40 +++++++++++++++++++++++++++++++++
 pkg/util/set_test.go            | 37 ++++++++++++++++++++++++++++++
 3 files changed, 84 insertions(+), 22 deletions(-)
 create mode 100644 pkg/util/set.go
 create mode 100644 pkg/util/set_test.go

diff --git a/pkg/registry/minion_registry.go b/pkg/registry/minion_registry.go
index dbe7fc5c994..62aa403d7c9 100644
--- a/pkg/registry/minion_registry.go
+++ b/pkg/registry/minion_registry.go
@@ -24,6 +24,7 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/apiserver"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
 )
 
 var ErrDoesNotExist = fmt.Errorf("The requested resource does not exist.")
@@ -39,32 +40,16 @@ type MinionRegistry interface {
 // Initialize a minion registry with a list of minions.
 func MakeMinionRegistry(minions []string) MinionRegistry {
 	m := &minionList{
-		minions: stringSet{},
+		minions: util.StringSet{},
 	}
 	for _, minion := range minions {
-		m.minions.insert(minion)
+		m.minions.Insert(minion)
 	}
 	return m
 }
 
-type empty struct{}
-type stringSet map[string]empty
-
-func (s stringSet) insert(item string) {
-	s[item] = empty{}
-}
-
-func (s stringSet) delete(item string) {
-	delete(s, item)
-}
-
-func (s stringSet) has(item string) bool {
-	_, contained := s[item]
-	return contained
-}
-
 type minionList struct {
-	minions stringSet
+	minions util.StringSet
 	lock    sync.Mutex
 }
 
@@ -82,21 +67,21 @@ func (m *minionList) List() (currentMinions []string, err error) {
 func (m *minionList) Insert(newMinion string) error {
 	m.lock.Lock()
 	defer m.lock.Unlock()
-	m.minions.insert(newMinion)
+	m.minions.Insert(newMinion)
 	return nil
 }
 
 func (m *minionList) Delete(minion string) error {
 	m.lock.Lock()
 	defer m.lock.Unlock()
-	m.minions.delete(minion)
+	m.minions.Delete(minion)
 	return nil
 }
 
 func (m *minionList) Contains(minion string) (bool, error) {
 	m.lock.Lock()
 	defer m.lock.Unlock()
-	return m.minions.has(minion), nil
+	return m.minions.Has(minion), nil
 }
 
 // MinionRegistryStorage implements the RESTStorage interface, backed by a MinionRegistry.
diff --git a/pkg/util/set.go b/pkg/util/set.go
new file mode 100644
index 00000000000..2b0db6002c5
--- /dev/null
+++ b/pkg/util/set.go
@@ -0,0 +1,40 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+type empty struct{}
+
+// A set of strings, implemented via map[string]struct{} for minimal memory consumption.
+type StringSet map[string]empty
+
+// Insert adds items to the set.
+func (s StringSet) Insert(items ...string) {
+	for _, item := range items {
+		s[item] = empty{}
+	}
+}
+
+// Delete removes item from the set.
+func (s StringSet) Delete(item string) {
+	delete(s, item)
+}
+
+// Has returns true iff item is contained in the set.
+func (s StringSet) Has(item string) bool {
+	_, contained := s[item]
+	return contained
+}
diff --git a/pkg/util/set_test.go b/pkg/util/set_test.go
new file mode 100644
index 00000000000..cc4323ac802
--- /dev/null
+++ b/pkg/util/set_test.go
@@ -0,0 +1,37 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+import (
+	"testing"
+)
+
+func TestStringSet(t *testing.T) {
+	s := StringSet{}
+	s.Insert("a", "b")
+	s.Insert("c")
+	if s.Has("d") {
+		t.Errorf("Unexpected contents: %#v", s)
+	}
+	if !s.Has("a") {
+		t.Errorf("Missing contents: %#v", s)
+	}
+	s.Delete("a")
+	if s.Has("a") {
+		t.Errorf("Unexpected contents: %#v", s)
+	}
+}