add restic integration for doing pod volume backups/restores

Signed-off-by: Steve Kriss <steve@heptio.com>

pkg/cmd/util/flag/enum.go

@@ -18,15 +18,13 @@ package flag
 
 import (
 	"github.com/pkg/errors"
-
-	"k8s.io/apimachinery/pkg/util/sets"
 )
 
 // Enum is a Cobra-compatible wrapper for defining
 // a string flag that can be one of a specified set
 // of values.
 type Enum struct {
-	allowedValues sets.String
+	allowedValues []string
 	value         string
 }
 
@@ -35,7 +33,7 @@ type Enum struct {
 // none is set.
 func NewEnum(defaultValue string, allowedValues ...string) *Enum {
 	return &Enum{
-		allowedValues: sets.NewString(allowedValues...),
+		allowedValues: allowedValues,
 		value:         defaultValue,
 	}
 }
@@ -50,12 +48,14 @@ func (e *Enum) String() string {
 // receiver. It returns an error if the string
 // is not an allowed value.
 func (e *Enum) Set(s string) error {
-	if !e.allowedValues.Has(s) {
-		return errors.Errorf("invalid value: %q", s)
+	for _, val := range e.allowedValues {
+		if val == s {
+			e.value = s
+			return nil
+		}
 	}
 
-	e.value = s
-	return nil
+	return errors.Errorf("invalid value: %q", s)
 }
 
 // Type returns a string representation of the
@@ -66,3 +66,9 @@ func (e *Enum) Type() string {
 	// the possible options.
 	return ""
 }
+
+// AllowedValues returns a slice of the flag's valid
+// values.
+func (e *Enum) AllowedValues() []string {
+	return e.allowedValues
+}

pkg/cmd/util/signals/signals.go

@@ -0,0 +1,39 @@
+/*
+Copyright 2018 the Heptio Ark contributors.
+
+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 signals
+
+import (
+	"context"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/sirupsen/logrus"
+)
+
+// CancelOnShutdown starts a goroutine that will call cancelFunc when
+// either SIGINT or SIGTERM is received
+func CancelOnShutdown(cancelFunc context.CancelFunc, logger logrus.FieldLogger) {
+	sigs := make(chan os.Signal, 1)
+	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		sig := <-sigs
+		logger.Infof("Received signal %s, shutting down", sig)
+		cancelFunc()
+	}()
+}