initial version

.gitignore

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+.vscode
+main
+k8s-volume-utils

README.md

@@ -1,2 +1,43 @@
 # k8s-volume-utils
-simple utils for k8s pv/pvc
+A simple tool to reuse PV. It can rename a PVC or move a PVC from one namespace to another namespace. After that we can resue bound PV without data lost
+
+# Usage:
+```
+k8s-volume-utils pvc
+   It is used to rename a PVC object in kubernetes cluster.
+   It will delete original PVC and create new PVC referring to same PV.
+   New PVC can be in another namespace.
+k8s-volume-utils pv
+   It can help to reuse a pv
+
+Usage:
+  k8s-volume-utils [command]
+
+Available Commands:
+  help        Help about any command
+  pv          help to reuse a pv
+  pvc         rename PVC object in kubernetes clusterd
+
+```
+# Example 
+1. create two namespaces for test  
+   `oc new-project pvc`  
+   `oc new-project pvc1`  
+    `oc project pvc ` 
+2. create a statefulset and it will create a PV.  
+   - Edit sts-pvc-test.yaml to update its `storageClassName` to available one on your cluster.  
+   - `oc create -f sts-pvc-test.yaml`  
+   - `oc get po www-pvc-test-0 -w ` to wait pod running. Then 
+     ```
+     $ oc exec pvc-test-0 cat /usr/share/nginx/html/a.txt
+      a
+     ```
+     We can see there is data in PV.
+3. delete the statefulset by `oc delete -f sts-pvc-test.yaml`. Now we have a pvc `www-pvc-test-0` to be reused by other service.
+4. move pvc to namespace pvc1 by `go run main.go pvc www-pvc-test-0 "" pvc1`   
+     `oc get pvc -n pvc1` to check PVC `www-pvc-test-0` is moved to namespace pvc1.  
+5. create another statefulset to reuse the same PV.  
+   -  Edit sts-pvc-test.yaml  
+      Change `"echo a > /usr/share/nginx/html/a.txt;sleep 3600"` to `"echo b > /usr/share/nginx/html/b.txt;sleep 3600"`
+   - `oc -n pvc1 create -f sts-pvc-test.yaml`
+   - when pod `pvc-test-0 ` is running in namespace `pvc1`. Run `oc exec pvc-test-0 cat /usr/share/nginx/html/a.txt -n pvc1` to check data is not lost.

cmd/pv.go

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+/*
+Copyright © 2020 NAME HERE <EMAIL ADDRESS>
+
+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 cmd
+
+import (
+	"os"
+
+	"github.com/IBM/k8s-volume-utils/pkg/kubeutils"
+	"github.com/spf13/cobra"
+	"k8s.io/klog"
+)
+
+// pvCmd represents the pv command
+var pvCmd = &cobra.Command{
+	Use:   "pv",
+	Short: "help to reuse a pv",
+	Long: `
+k8s-volume-utils pv retain "pvName": change pv reclaim policy to retain
+k8s-volume-utils pv resue "pvName": change pv status to available so that it is ready to be bound to pvc
+
+`,
+	Args: cobra.ExactArgs(2),
+	Run: func(cmd *cobra.Command, args []string) {
+		if args[0] == "retain" {
+			err := kubeutils.RetainPV(args[1])
+			if err != nil {
+				os.Exit(1)
+			}
+		} else if args[0] == "reuse" {
+			err := kubeutils.ReusePV(args[1])
+			if err != nil {
+				os.Exit(1)
+			}
+
+		} else {
+			klog.Error("invalid argument. should be retain or reuse")
+			os.Exit(1)
+		}
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(pvCmd)
+
+	// Here you will define your flags and configuration settings.
+
+	// Cobra supports Persistent Flags which will work for this command
+	// and all subcommands, e.g.:
+	// pvCmd.PersistentFlags().String("foo", "", "A help for foo")
+
+	// Cobra supports local flags which will only run when this command
+	// is called directly, e.g.:
+	// pvCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
+}

cmd/pvc.go

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+//
+// Copyright 2020 IBM Corporation
+//
+// 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 cmd
+
+import (
+	"os"
+
+	"github.com/IBM/k8s-volume-utils/pkg/kubeutils"
+	"github.com/spf13/cobra"
+)
+
+// pvcCmd represents the pvc command
+var pvcCmd = &cobra.Command{
+	Use:   "pvc",
+	Short: "rename PVC object in kubernetes clusterd",
+	Long: `
+Examples:
+  k8s-volume-utils pvc "name" "targetName" "targetNamespace", "namespace"
+  k8s-volume-utils pvc "name" "targetName" "targetNamespace"
+  k8s-volume-utils pvc "name" "targetName"
+Paramethers:
+  name: pvc name to be renamed
+  targetName: pvc name to be renamed to
+  targetNamespace: namespace of new pvc
+  namespace: namespace of the source pvc
+
+`,
+	Args: cobra.RangeArgs(2, 4),
+	Run: func(cmd *cobra.Command, args []string) {
+		var err error
+		if len(args) == 4 {
+			err = kubeutils.RenamePVC(args[0], args[1], args[2], args[3])
+
+		}
+		if len(args) == 3 {
+			err = kubeutils.RenamePVC(args[0], args[1], args[2], "")
+
+		}
+		if len(args) == 2 {
+			err = kubeutils.RenamePVC(args[0], args[1], "", "")
+
+		}
+		if err != nil {
+			os.Exit(1)
+		}
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(pvcCmd)
+
+	// Here you will define your flags and configuration settings.
+
+	// Cobra supports Persistent Flags which will work for this command
+	// and all subcommands, e.g.:
+	// pvcCmd.PersistentFlags().String("foo", "", "A help for foo")
+
+	// Cobra supports local flags which will only run when this command
+	// is called directly, e.g.:
+	// pvcCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
+}

cmd/root.go

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+//
+// Copyright 2020 IBM Corporation
+//
+// 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 cmd
+
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	"github.com/IBM/k8s-volume-utils/pkg/kubeutils"
+	"github.com/spf13/cobra"
+	"k8s.io/cli-runtime/pkg/genericclioptions"
+	"k8s.io/klog"
+	cmdutil "k8s.io/kubectl/pkg/cmd/util"
+)
+
+// rootCmd represents the base command when called without any subcommands
+var rootCmd = &cobra.Command{
+	Use:   "k8s-volume-utils",
+	Short: "it is used to rename PVC object or help to reuse pv",
+	Long: `
+k8s-volume-utils pvc
+   It is used to rename a PVC object in kubernetes cluster.
+   It will delete original PVC and create new PVC referring to same PV.
+   New PVC can be in another namespace.
+k8s-volume-utils pv
+   It can help to reuse a pv
+`,
+	// Uncomment the following line if your bare application
+	// has an action associated with it:
+	//	Run: func(cmd *cobra.Command, args []string) { },
+}
+
+// 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() {
+	klog.InitFlags(nil)
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+func init() {
+	flags := rootCmd.PersistentFlags()
+
+	kubeConfigFlags := genericclioptions.NewConfigFlags(true).WithDeprecatedPasswordFlag()
+	kubeConfigFlags.AddFlags(flags)
+	matchVersionKubeConfigFlags := cmdutil.NewMatchVersionFlags(kubeConfigFlags)
+	matchVersionKubeConfigFlags.AddFlags(rootCmd.PersistentFlags())
+
+	rootCmd.PersistentFlags().AddGoFlagSet(flag.CommandLine)
+
+	f := cmdutil.NewFactory(matchVersionKubeConfigFlags)
+	var namespace string
+	var err error
+	namespace, _, err = f.ToRawKubeConfigLoader().Namespace()
+	if err != nil {
+		klog.Errorf("fail to get default namespace: %s", err.Error())
+	}
+
+	client, e := f.KubernetesClientSet()
+	if e != nil {
+		klog.Errorf("fail to get kubeclient: %s", e.Error())
+	}
+	kubeutils.InitKube(client, namespace)
+	klog.Infof("kubeclient initialized. default namespace: %s", namespace)
+}

go.mod

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+module github.com/IBM/k8s-volume-utils
+
+go 1.13
+
+require (
+	github.com/evanphx/json-patch v4.5.0+incompatible // indirect
+	github.com/googleapis/gnostic v0.3.1 // indirect
+	github.com/imdario/mergo v0.3.6 // indirect
+	github.com/onsi/ginkgo v1.11.0 // indirect
+	github.com/onsi/gomega v1.8.1 // indirect
+	github.com/pkg/errors v0.8.1 // indirect
+	github.com/spf13/cobra v0.0.7
+	github.com/spf13/pflag v1.0.5 // indirect
+	golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550 // indirect
+	golang.org/x/sys v0.0.0-20190922100055-0a153f010e69 // indirect
+	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect
+	gopkg.in/yaml.v2 v2.2.7 // indirect
+	k8s.io/api v0.18.0
+	k8s.io/apimachinery v0.18.0
+	k8s.io/cli-runtime v0.0.0
+	k8s.io/client-go v0.18.0
+	k8s.io/klog v1.0.0
+	k8s.io/kubectl v0.0.0
+	k8s.io/utils v0.0.0-20191114184206-e782cd3c129f // indirect
+)
+
+// Pinned to kubernetes-1.16.2
+replace (
+	k8s.io/api => k8s.io/api v0.0.0-20191016110408-35e52d86657a
+	k8s.io/apiextensions-apiserver => k8s.io/apiextensions-apiserver v0.0.0-20191016113550-5357c4baaf65
+	k8s.io/apimachinery => k8s.io/apimachinery v0.0.0-20191004115801-a2eda9f80ab8
+	k8s.io/apiserver => k8s.io/apiserver v0.0.0-20191016112112-5190913f932d
+	k8s.io/cli-runtime => k8s.io/cli-runtime v0.0.0-20191016114015-74ad18325ed5
+	k8s.io/client-go => k8s.io/client-go v0.0.0-20191016111102-bec269661e48
+	k8s.io/cloud-provider => k8s.io/cloud-provider v0.0.0-20191016115326-20453efc2458
+	k8s.io/cluster-bootstrap => k8s.io/cluster-bootstrap v0.0.0-20191016115129-c07a134afb42
+	k8s.io/code-generator => k8s.io/code-generator v0.0.0-20191004115455-8e001e5d1894
+	k8s.io/component-base => k8s.io/component-base v0.0.0-20191016111319-039242c015a9
+	k8s.io/cri-api => k8s.io/cri-api v0.0.0-20190828162817-608eb1dad4ac
+	k8s.io/csi-translation-lib => k8s.io/csi-translation-lib v0.0.0-20191016115521-756ffa5af0bd
+	k8s.io/kube-aggregator => k8s.io/kube-aggregator v0.0.0-20191016112429-9587704a8ad4
+	k8s.io/kube-controller-manager => k8s.io/kube-controller-manager v0.0.0-20191016114939-2b2b218dc1df
+	k8s.io/kube-proxy => k8s.io/kube-proxy v0.0.0-20191016114407-2e83b6f20229
+	k8s.io/kube-scheduler => k8s.io/kube-scheduler v0.0.0-20191016114748-65049c67a58b
+	k8s.io/kubectl => k8s.io/kubectl v0.0.0-20191016120415-2ed914427d51
+	k8s.io/kubelet => k8s.io/kubelet v0.0.0-20191016114556-7841ed97f1b2
+	k8s.io/legacy-cloud-providers => k8s.io/legacy-cloud-providers v0.0.0-20191016115753-cf0698c3a16b
+	k8s.io/metrics => k8s.io/metrics v0.0.0-20191016113814-3b1a734dba6e
+	k8s.io/sample-apiserver => k8s.io/sample-apiserver v0.0.0-20191016112829-06bb3c9d77c9
+)