refactor code logic for cloud-controller manager

cmd/controller-manager/app/helper.go

@@ -21,6 +21,7 @@ import (
 	"net/http"
 	"time"
 
+	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/wait"
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/klog"
@@ -53,3 +54,26 @@ func WaitForAPIServer(client clientset.Interface, timeout time.Duration) error {
 
 	return nil
 }
+
+// IsControllerEnabled check if a specified controller enabled or not.
+func IsControllerEnabled(name string, disabledByDefaultControllers sets.String, controllers []string) bool {
+	hasStar := false
+	for _, ctrl := range controllers {
+		if ctrl == name {
+			return true
+		}
+		if ctrl == "-"+name {
+			return false
+		}
+		if ctrl == "*" {
+			hasStar = true
+		}
+	}
+	// if we get here, there was no explicit choice
+	if !hasStar {
+		// nothing on by default
+		return false
+	}
+
+	return !disabledByDefaultControllers.Has(name)
+}

cmd/controller-manager/app/helper_test.go

@@ -0,0 +1,77 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+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 app
+
+import (
+	"testing"
+
+	"k8s.io/apimachinery/pkg/util/sets"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIsControllerEnabled(t *testing.T) {
+	tcs := []struct {
+		name                         string
+		controllerName               string
+		controllers                  []string
+		disabledByDefaultControllers []string
+		expected                     bool
+	}{
+		{
+			name:                         "on by name",
+			controllerName:               "bravo",
+			controllers:                  []string{"alpha", "bravo", "-charlie"},
+			disabledByDefaultControllers: []string{"delta", "echo"},
+			expected:                     true,
+		},
+		{
+			name:                         "off by name",
+			controllerName:               "charlie",
+			controllers:                  []string{"alpha", "bravo", "-charlie"},
+			disabledByDefaultControllers: []string{"delta", "echo"},
+			expected:                     false,
+		},
+		{
+			name:                         "on by default",
+			controllerName:               "alpha",
+			controllers:                  []string{"*"},
+			disabledByDefaultControllers: []string{"delta", "echo"},
+			expected:                     true,
+		},
+		{
+			name:                         "off by default",
+			controllerName:               "delta",
+			controllers:                  []string{"*"},
+			disabledByDefaultControllers: []string{"delta", "echo"},
+			expected:                     false,
+		},
+		{
+			name:                         "off by default implicit, no star",
+			controllerName:               "foxtrot",
+			controllers:                  []string{"alpha", "bravo", "-charlie"},
+			disabledByDefaultControllers: []string{"delta", "echo"},
+			expected:                     false,
+		},
+	}
+
+	for _, tc := range tcs {
+		actual := IsControllerEnabled(tc.controllerName, sets.NewString(tc.disabledByDefaultControllers...), tc.controllers)
+		assert.Equal(t, tc.expected, actual, "%v: expected %v, got %v", tc.name, tc.expected, actual)
+	}
+
+}