Move the authorization mode constants into a separate package

pkg/kubeapiserver/authorizer/modes/BUILD

@@ -0,0 +1,35 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+    "go_test",
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["modes_test.go"],
+    library = ":go_default_library",
+    tags = ["automanaged"],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["modes.go"],
+    tags = ["automanaged"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+)

pkg/kubeapiserver/authorizer/modes/modes.go

@@ -0,0 +1,37 @@
+/*
+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 modes
+
+const (
+	ModeAlwaysAllow string = "AlwaysAllow"
+	ModeAlwaysDeny  string = "AlwaysDeny"
+	ModeABAC        string = "ABAC"
+	ModeWebhook     string = "Webhook"
+	ModeRBAC        string = "RBAC"
+)
+
+var AuthorizationModeChoices = []string{ModeAlwaysAllow, ModeAlwaysDeny, ModeABAC, ModeWebhook, ModeRBAC}
+
+// IsValidAuthorizationMode returns true if the given authorization mode is a valid one for the apiserver
+func IsValidAuthorizationMode(authzMode string) bool {
+	for _, validMode := range AuthorizationModeChoices {
+		if authzMode == validMode {
+			return true
+		}
+	}
+	return false
+}

pkg/kubeapiserver/authorizer/modes/modes_test.go

@@ -0,0 +1,45 @@
+/*
+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 modes
+
+import "testing"
+
+func TestIsValidAuthorizationMode(t *testing.T) {
+	var tests = []struct {
+		authzMode string
+		expected  bool
+	}{
+		{"", false},
+		{"rBAC", false},        // not supported
+		{"falsy value", false}, // not supported
+		{"RBAC", true},         // supported
+		{"ABAC", true},         // supported
+		{"Webhook", true},      // supported
+		{"AlwaysAllow", true},  // supported
+		{"AlwaysDeny", true},   // supported
+	}
+	for _, rt := range tests {
+		actual := IsValidAuthorizationMode(rt.authzMode)
+		if actual != rt.expected {
+			t.Errorf(
+				"failed ValidAuthorizationMode:\n\texpected: %t\n\t  actual: %t",
+				rt.expected,
+				actual,
+			)
+		}
+	}
+}