initial commit

.gitignore

@@ -0,0 +1,27 @@
+# Created by https://www.toptal.com/developers/gitignore/api/go
+# Edit at https://www.toptal.com/developers/gitignore?templates=go
+
+### Go ###
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+### Go Patch ###
+/vendor/
+/Godeps/
+
+# End of https://www.toptal.com/developers/gitignore/api/go
+
+bin/**

Makefile

@@ -0,0 +1,16 @@
+.PHONY: build mover
+
+build:
+	go build -v -o bin/korb
+
+build-final:
+	GOOS=linux GOARCH=arm go build -v -o bin/korb-linux-arm
+	GOOS=linux GOARCH=arm64 go build -v -o bin/korb-linux-arm64
+	GOOS=linux GOARCH=amd64 go build -v -o bin/korb-linux-amd64
+	GOOS=darwin GOARCH=amd64 go build -v -o bin/korb-darwin-amd64
+
+mover:
+	cd mover/ && docker build -t beryju/korb-mover .
+	docker push beryju/korb-mover
+
+all: build mover

cmd/root.go

@@ -0,0 +1,62 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/BeryJu/korb/pkg/config"
+	"github.com/BeryJu/korb/pkg/migrator"
+	log "github.com/sirupsen/logrus"
+
+	"github.com/spf13/cobra"
+	"k8s.io/client-go/util/homedir"
+)
+
+var kubeConfig string
+
+var pvcNewStorageClass string
+var pvcNewSize string
+
+var force bool
+
+// rootCmd represents the base command when called without any subcommands
+var rootCmd = &cobra.Command{
+	Use:  "k8s-storage-mover",
+	Long: `Move data between Kubernetes PVCs on different Storage Classes.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		m := migrator.New(kubeConfig)
+		m.Force = force
+
+		m.DestPVCSize = pvcNewSize
+		m.DestPVCStorageClass = pvcNewStorageClass
+		m.SourcePVCName = args[0]
+		m.Run()
+	},
+}
+
+// Execute adds all child commands to the root command and sets flags appropriately.
+// This is called by main.main(). It only needs to happen once to the rootCmd.
+func Execute() {
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+
+func init() {
+	log.SetLevel(log.DebugLevel)
+
+	if home := homedir.HomeDir(); home != "" {
+		rootCmd.Flags().StringVar(&kubeConfig, "kubeConfig", filepath.Join(home, ".kube", "config"), "(optional) absolute path to the kubeConfig file")
+	} else {
+		rootCmd.Flags().StringVar(&kubeConfig, "kubeConfig", "", "absolute path to the kubeconfig file")
+	}
+
+	rootCmd.Flags().StringVar(&pvcNewStorageClass, "new-pvc-storage-class", "", "Storage class to use for the new PVC. If empty, the storage class of the source will be used.")
+	rootCmd.Flags().StringVar(&pvcNewSize, "new-pvc-size", "", "Size for the new PVC. If empty, the size of the source will be used. Accepts formats like used in Kubernetes Manifests (Gi, Ti, ...)")
+
+	rootCmd.Flags().BoolVar(&force, "force", false, "Ignore warning which would normally halt the tool during validation.")
+
+	rootCmd.Flags().StringVar(&config.DockerImage, "docker-image", config.DockerImage, "Image to use for moving jobs")
+}

go.mod

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+module github.com/BeryJu/korb
+
+go 1.15
+
+require (
+	github.com/imdario/mergo v0.3.11 // indirect
+	github.com/mitchellh/go-homedir v1.1.0
+	github.com/sirupsen/logrus v1.2.0
+	github.com/spf13/cobra v1.1.1
+	github.com/spf13/viper v1.7.1
+	k8s.io/api v0.19.3
+	k8s.io/apimachinery v0.19.3
+	k8s.io/client-go v0.19.0
+	k8s.io/klog v1.0.0 // indirect
+	k8s.io/utils v0.0.0-20201104234853-8146046b121e // indirect
+)

hack/test-deployment.yaml

@@ -0,0 +1,37 @@
+kind: PersistentVolumeClaim
+apiVersion: v1
+metadata:
+  name: source-pvc
+spec:
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 10Gi
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: test-deployment
+spec:
+  selector:
+    matchLabels:
+      app: test-deployment
+  template:
+    metadata:
+      labels:
+        app: test-deployment
+    spec:
+      containers:
+      - name: test-deployment
+        image: ubuntu:latest
+        # Just spin & wait forever
+        command: [ "/bin/bash", "-c", "--" ]
+        args: [ "while true; do sleep 30; done;" ]
+        volumeMounts:
+        - name: source-pvc
+          mountPath: /source
+      volumes:
+      - name: source-pvc
+        persistentVolumeClaim:
+          claimName: source-pvc

main.go

@@ -0,0 +1,7 @@
+package main
+
+import "github.com/BeryJu/korb/cmd"
+
+func main() {
+  cmd.Execute()
+}

mover/Dockerfile

@@ -0,0 +1,7 @@
+FROM alpine:3.12
+
+RUN apk add --no-cache rsync && rm -rf /var/cache/apk/*
+
+VOLUME [ "/source", "/dest" ]
+
+CMD [ "rsync", "-aHA", "--progress", "/source/", "/dest" ]

pkg/config/config.go

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+package config
+
+var DockerImage = "beryju/korb-mover:latest"

pkg/migrator/destination.go

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+package migrator
+
+import (
+	v1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func (m *Migrator) GetDestPVCSize(fallback resource.Quantity) resource.Quantity {
+	var destSize resource.Quantity
+	if m.DestPVCSize != "" {
+		destSize = resource.MustParse(m.DestPVCSize)
+	} else {
+		destSize = fallback
+	}
+	return destSize
+}
+
+func (m *Migrator) GetDestinationPVCTemplate(sourcePVC *v1.PersistentVolumeClaim) *v1.PersistentVolumeClaim {
+	var sc *string
+	if m.DestPVCStorageClass != "" {
+		sc = &m.DestPVCStorageClass
+	}
+	destPVC := &v1.PersistentVolumeClaim{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      m.SourcePVCName,
+			Namespace: m.kNS,
+		},
+		Spec: v1.PersistentVolumeClaimSpec{
+			AccessModes: sourcePVC.Spec.AccessModes,
+			Resources: v1.ResourceRequirements{
+				Requests: v1.ResourceList{
+					v1.ResourceName(v1.ResourceStorage): m.GetDestPVCSize(*sourcePVC.Spec.Resources.Requests.Storage()),
+				},
+			},
+			StorageClassName: sc,
+		},
+	}
+	return destPVC
+}

pkg/migrator/migrator.go

@@ -0,0 +1,77 @@
+package migrator
+
+import (
+	log "github.com/sirupsen/logrus"
+
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
+)
+
+type Migrator struct {
+	SourcePVCName string
+
+	DestPVCStorageClass string
+	DestPVCSize         string
+
+	Force bool
+
+	kConfig *rest.Config
+	kClient *kubernetes.Clientset
+	kNS     string
+
+	log *log.Entry
+}
+
+func New(kubeconfigPath string) *Migrator {
+	m := &Migrator{
+		log: log.WithField("component", "migrator"),
+	}
+	if kubeconfigPath != "" {
+		m.log.WithField("kubeconfig", kubeconfigPath).Debug("Created client from kubeconfig")
+		cc := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
+			&clientcmd.ClientConfigLoadingRules{ExplicitPath: kubeconfigPath},
+			&clientcmd.ConfigOverrides{})
+
+		// use the current context in kubeconfig
+		config, err := cc.ClientConfig()
+
+		if err != nil {
+			m.log.WithError(err).Panic("Failed to get client config")
+		}
+		m.kConfig = config
+		ns, _, err := cc.Namespace()
+		if err != nil {
+			m.log.WithError(err).Panic("Failed to get current namespace")
+		} else {
+			m.log.WithField("namespace", ns).Debug("Got current namespace")
+			m.kNS = ns
+		}
+	} else {
+		m.log.Panic("Kubeconfig cannot be empty")
+	}
+
+	// create the clientset
+	clientset, err := kubernetes.NewForConfig(m.kConfig)
+	if err != nil {
+		panic(err.Error())
+	}
+	m.kClient = clientset
+	return m
+}
+
+func (m *Migrator) Run() {
+	sourcePVC, compatibleStrategies := m.Validate()
+	m.log.Debug("Compatible Strategies:")
+	for _, compatibleStrategy := range compatibleStrategies {
+		m.log.Debug(compatibleStrategy.Description())
+	}
+	destTemplate := m.GetDestinationPVCTemplate(sourcePVC)
+	if len(compatibleStrategies) == 1 {
+		m.log.Debug("Only one compatible strategy, running")
+		err := compatibleStrategies[0].Do(sourcePVC, destTemplate)
+		if err != nil {
+			m.log.WithError(err).Warning("Failed to migrate")
+		}
+	}
+}

pkg/migrator/validate.go

@@ -0,0 +1,46 @@
+package migrator
+
+import (
+	"context"
+
+	"github.com/BeryJu/korb/pkg/strategies"
+	v1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func (m *Migrator) Validate() (*v1.PersistentVolumeClaim, []strategies.Strategy) {
+	pvc := m.validateSourcePVC()
+	controllers, err := m.getPVCControllers(pvc)
+	if err != nil {
+		m.log.WithError(err).Panic("Failed to get controllers")
+	}
+	baseStrategy := strategies.NewBaseStrategy(m.kConfig, m.kClient, m.kNS)
+	allStrategies := strategies.StrategyInstances(baseStrategy)
+	compatibleStrategies := make([]strategies.Strategy, 0)
+	for _, strategy := range allStrategies {
+		if strategy.CompatibleWithControllers(controllers...) {
+			compatibleStrategies = append(compatibleStrategies, strategy)
+		}
+	}
+	return pvc, compatibleStrategies
+}
+
+func (m *Migrator) validateSourcePVC() *v1.PersistentVolumeClaim {
+	pvc, err := m.kClient.CoreV1().PersistentVolumeClaims(m.kNS).Get(context.TODO(), m.SourcePVCName, metav1.GetOptions{})
+	if err != nil {
+		m.log.WithError(err).Panic("Failed to get Source PVC")
+	}
+	m.log.WithField("uid", pvc.UID).WithField("name", pvc.Name).Debug("Got Source PVC")
+	destPVCTemplate := m.GetDestinationPVCTemplate(pvc)
+	sourceSize := pvc.Spec.Resources.Requests.Storage()
+	destSize := destPVCTemplate.Spec.Resources.Requests.Storage()
+	if sourceSize.Cmp(*destSize) == 1 {
+		l := m.log.WithField("src-size", sourceSize.String()).WithField("destSize", destSize.String())
+		if m.Force {
+			l.Warning("Destination PVC is smaller than source, ignoring because force.")
+		} else {
+			l.Panic("Destination PVC is smaller than source.")
+		}
+	}
+	return pvc
+}

pkg/migrator/validateController.go

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+package migrator
+
+import (
+	appsv1 "k8s.io/api/apps/v1"
+	corev1 "k8s.io/api/core/v1"
+)
+
+func (m *Migrator) getPVCControllers(pvc *corev1.PersistentVolumeClaim) ([]interface{}, error) {
+	pods, err := m.getPVCPods(pvc)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, pod := range pods {
+		for _, owner := range m.resolveOwner(pod.ObjectMeta, &appsv1.StatefulSet{}) {
+			switch owner.(type) {
+			case *appsv1.Deployment:
+				m.log.Debug("Found deployment")
+			case *appsv1.StatefulSet:
+				m.log.Debug("Found statefulset")
+			}
+		}
+	}
+
+	return nil, nil
+}

pkg/migrator/validateDeployments.go

@@ -0,0 +1,22 @@
+package migrator
+
+import (
+	appsv1 "k8s.io/api/apps/v1"
+	corev1 "k8s.io/api/core/v1"
+)
+
+func (m *Migrator) getPVCDeployments(pvc *corev1.PersistentVolumeClaim) ([]*appsv1.Deployment, error) {
+	pods, err := m.getPVCPods(pvc)
+	if err != nil {
+		return nil, err
+	}
+
+	affectedOwners := make([]*appsv1.Deployment, 0)
+	for _, pod := range pods {
+		for _, owner := range m.resolveOwner(pod.ObjectMeta, &appsv1.Deployment{}) {
+			affectedOwners = append(affectedOwners, owner.(*appsv1.Deployment))
+		}
+	}
+
+	return affectedOwners, nil
+}