Add the ability to list etcd snapshots (k3s-io#3303)

* add ability to list local and s3 etcd snapshots

cmd/etcdsnapshot/main.go

@@ -13,7 +13,7 @@ import (
 func main() {
 	app := cmds.NewApp()
 	app.Commands = []cli.Command{
-		cmds.NewEtcdSnapshotCommand(etcdsnapshot.Run, cmds.NewEtcdSnapshotSubcommands(etcdsnapshot.Delete)),
+		cmds.NewEtcdSnapshotCommand(etcdsnapshot.Run, cmds.NewEtcdSnapshotSubcommands(etcdsnapshot.Delete, etcdsnapshot.List)),
 	}
 
 	if err := app.Run(configfilearg.MustParse(os.Args)); err != nil {

cmd/k3s/main.go

@@ -44,7 +44,7 @@ func main() {
 		cmds.NewCRICTL(externalCLIAction("crictl", dataDir)),
 		cmds.NewCtrCommand(externalCLIAction("ctr", dataDir)),
 		cmds.NewCheckConfigCommand(externalCLIAction("check-config", dataDir)),
-		cmds.NewEtcdSnapshotCommand(etcdsnapshotCommand, cmds.NewEtcdSnapshotSubcommands(etcdsnapshotCommand)),
+		cmds.NewEtcdSnapshotCommand(etcdsnapshotCommand, cmds.NewEtcdSnapshotSubcommands(etcdsnapshotCommand, etcdsnapshotCommand)),
 	}
 
 	if err := app.Run(os.Args); err != nil {

cmd/server/main.go

@@ -43,7 +43,7 @@ func main() {
 		cmds.NewKubectlCommand(kubectl.Run),
 		cmds.NewCRICTL(crictl.Run),
 		cmds.NewCtrCommand(ctr.Run),
-		cmds.NewEtcdSnapshotCommand(etcdsnapshot.Run, cmds.NewEtcdSnapshotSubcommands(etcdsnapshot.Delete)),
+		cmds.NewEtcdSnapshotCommand(etcdsnapshot.Run, cmds.NewEtcdSnapshotSubcommands(etcdsnapshot.Delete, etcdsnapshot.List)),
 	}
 
 	err := app.Run(configfilearg.MustParse(os.Args))

main.go

@@ -27,7 +27,7 @@ func main() {
 		cmds.NewAgentCommand(agent.Run),
 		cmds.NewKubectlCommand(kubectl.Run),
 		cmds.NewCRICTL(crictl.Run),
-		cmds.NewEtcdSnapshotCommand(etcdsnapshot.Run, cmds.NewEtcdSnapshotSubcommands(etcdsnapshot.Delete)),
+		cmds.NewEtcdSnapshotCommand(etcdsnapshot.Run, cmds.NewEtcdSnapshotSubcommands(etcdsnapshot.Delete, etcdsnapshot.List)),
 	}
 
 	if err := app.Run(configfilearg.MustParse(os.Args)); err != nil {

pkg/cli/cmds/etcd_snapshot.go

@@ -95,7 +95,7 @@ func NewEtcdSnapshotCommand(action func(*cli.Context) error, subcommands []cli.C
 	}
 }
 
-func NewEtcdSnapshotSubcommands(delete func(ctx *cli.Context) error) []cli.Command {
+func NewEtcdSnapshotSubcommands(delete, list func(ctx *cli.Context) error) []cli.Command {
 	return []cli.Command{
 		{
 			Name:            "delete",
@@ -105,5 +105,14 @@ func NewEtcdSnapshotSubcommands(delete func(ctx *cli.Context) error) []cli.Comma
 			Action:          delete,
 			Flags:           EtcdSnapshotFlags,
 		},
+		{
+			Name:            "ls",
+			Aliases:         []string{"list", "l"},
+			Usage:           "List etcd snapshots",
+			SkipFlagParsing: false,
+			SkipArgReorder:  true,
+			Action:          list,
+			Flags:           EtcdSnapshotFlags,
+		},
 	}
 }

pkg/cli/etcdsnapshot/etcd_snapshot.go

@@ -3,8 +3,11 @@ package etcdsnapshot
 import (
 	"context"
 	"errors"
+	"fmt"
 	"os"
 	"path/filepath"
+	"text/tabwriter"
+	"time"
 
 	"github.com/erikdubbelboer/gspt"
 	"github.com/rancher/k3s/pkg/cli/cmds"
@@ -18,7 +21,7 @@ import (
 
 // commandSetup setups up common things needed
 // for each etcd command.
-func commandSetup(app *cli.Context, cfg *cmds.Server) (string, error) {
+func commandSetup(app *cli.Context, cfg *cmds.Server, sc *server.Config) (string, error) {
 	gspt.SetProcTitle(os.Args[0])
 
 	nodeName := app.String("node-name")
@@ -32,6 +35,21 @@ func commandSetup(app *cli.Context, cfg *cmds.Server) (string, error) {
 
 	os.Setenv("NODE_NAME", nodeName)
 
+	sc.DisableAgent = true
+	sc.ControlConfig.DataDir = cfg.DataDir
+	sc.ControlConfig.EtcdSnapshotName = cfg.EtcdSnapshotName
+	sc.ControlConfig.EtcdSnapshotDir = cfg.EtcdSnapshotDir
+	sc.ControlConfig.EtcdS3 = cfg.EtcdS3
+	sc.ControlConfig.EtcdS3Endpoint = cfg.EtcdS3Endpoint
+	sc.ControlConfig.EtcdS3EndpointCA = cfg.EtcdS3EndpointCA
+	sc.ControlConfig.EtcdS3SkipSSLVerify = cfg.EtcdS3SkipSSLVerify
+	sc.ControlConfig.EtcdS3AccessKey = cfg.EtcdS3AccessKey
+	sc.ControlConfig.EtcdS3SecretKey = cfg.EtcdS3SecretKey
+	sc.ControlConfig.EtcdS3BucketName = cfg.EtcdS3BucketName
+	sc.ControlConfig.EtcdS3Region = cfg.EtcdS3Region
+	sc.ControlConfig.EtcdS3Folder = cfg.EtcdS3Folder
+	sc.ControlConfig.Runtime = &config.ControlRuntime{}
+
 	return server.ResolveDataDir(cfg.DataDir)
 }
 
@@ -43,7 +61,9 @@ func Run(app *cli.Context) error {
 }
 
 func run(app *cli.Context, cfg *cmds.Server) error {
-	dataDir, err := commandSetup(app, cfg)
+	var serverConfig server.Config
+
+	dataDir, err := commandSetup(app, cfg, &serverConfig)
 	if err != nil {
 		return err
 	}
@@ -52,22 +72,8 @@ func run(app *cli.Context, cfg *cmds.Server) error {
 		return cmds.ErrCommandNoArgs
 	}
 
-	var serverConfig server.Config
-	serverConfig.DisableAgent = true
 	serverConfig.ControlConfig.DataDir = dataDir
-	serverConfig.ControlConfig.EtcdSnapshotName = cfg.EtcdSnapshotName
-	serverConfig.ControlConfig.EtcdSnapshotDir = cfg.EtcdSnapshotDir
 	serverConfig.ControlConfig.EtcdSnapshotRetention = 0 // disable retention check
-	serverConfig.ControlConfig.EtcdS3 = cfg.EtcdS3
-	serverConfig.ControlConfig.EtcdS3Endpoint = cfg.EtcdS3Endpoint
-	serverConfig.ControlConfig.EtcdS3EndpointCA = cfg.EtcdS3EndpointCA
-	serverConfig.ControlConfig.EtcdS3SkipSSLVerify = cfg.EtcdS3SkipSSLVerify
-	serverConfig.ControlConfig.EtcdS3AccessKey = cfg.EtcdS3AccessKey
-	serverConfig.ControlConfig.EtcdS3SecretKey = cfg.EtcdS3SecretKey
-	serverConfig.ControlConfig.EtcdS3BucketName = cfg.EtcdS3BucketName
-	serverConfig.ControlConfig.EtcdS3Region = cfg.EtcdS3Region
-	serverConfig.ControlConfig.EtcdS3Folder = cfg.EtcdS3Folder
-	serverConfig.ControlConfig.Runtime = &config.ControlRuntime{}
 	serverConfig.ControlConfig.Runtime.ETCDServerCA = filepath.Join(dataDir, "tls", "etcd", "server-ca.crt")
 	serverConfig.ControlConfig.Runtime.ClientETCDCert = filepath.Join(dataDir, "tls", "etcd", "client.crt")
 	serverConfig.ControlConfig.Runtime.ClientETCDKey = filepath.Join(dataDir, "tls", "etcd", "client.key")
@@ -108,7 +114,9 @@ func Delete(app *cli.Context) error {
 }
 
 func delete(app *cli.Context, cfg *cmds.Server) error {
-	dataDir, err := commandSetup(app, cfg)
+	var serverConfig server.Config
+
+	dataDir, err := commandSetup(app, cfg, &serverConfig)
 	if err != nil {
 		return err
 	}
@@ -118,21 +126,7 @@ func delete(app *cli.Context, cfg *cmds.Server) error {
 		return errors.New("no snapshots given for removal")
 	}
 
-	var serverConfig server.Config
-	serverConfig.DisableAgent = true
 	serverConfig.ControlConfig.DataDir = dataDir
-	serverConfig.ControlConfig.EtcdSnapshotName = cfg.EtcdSnapshotName
-	serverConfig.ControlConfig.EtcdSnapshotDir = cfg.EtcdSnapshotDir
-	serverConfig.ControlConfig.EtcdS3 = cfg.EtcdS3
-	serverConfig.ControlConfig.EtcdS3Endpoint = cfg.EtcdS3Endpoint
-	serverConfig.ControlConfig.EtcdS3EndpointCA = cfg.EtcdS3EndpointCA
-	serverConfig.ControlConfig.EtcdS3SkipSSLVerify = cfg.EtcdS3SkipSSLVerify
-	serverConfig.ControlConfig.EtcdS3AccessKey = cfg.EtcdS3AccessKey
-	serverConfig.ControlConfig.EtcdS3SecretKey = cfg.EtcdS3SecretKey
-	serverConfig.ControlConfig.EtcdS3BucketName = cfg.EtcdS3BucketName
-	serverConfig.ControlConfig.EtcdS3Region = cfg.EtcdS3Region
-	serverConfig.ControlConfig.EtcdS3Folder = cfg.EtcdS3Folder
-	serverConfig.ControlConfig.Runtime = &config.ControlRuntime{}
 	serverConfig.ControlConfig.Runtime.KubeConfigAdmin = filepath.Join(dataDir, "cred", "admin.kubeconfig")
 
 	ctx := signals.SetupSignalHandler(context.Background())
@@ -147,3 +141,43 @@ func delete(app *cli.Context, cfg *cmds.Server) error {
 
 	return e.DeleteSnapshots(ctx, app.Args())
 }
+
+func List(app *cli.Context) error {
+	if err := cmds.InitLogging(); err != nil {
+		return err
+	}
+	return list(app, &cmds.ServerConfig)
+}
+
+func list(app *cli.Context, cfg *cmds.Server) error {
+	var serverConfig server.Config
+
+	dataDir, err := commandSetup(app, cfg, &serverConfig)
+	if err != nil {
+		return err
+	}
+
+	serverConfig.ControlConfig.DataDir = dataDir
+
+	ctx := signals.SetupSignalHandler(context.Background())
+	e := etcd.NewETCD()
+	e.SetControlConfig(&serverConfig.ControlConfig)
+
+	sf, err := e.ListSnapshots(ctx)
+	if err != nil {
+		return err
+	}
+
+	w := tabwriter.NewWriter(os.Stdout, 0, 0, 1, ' ', 0)
+	defer w.Flush()
+
+	for _, s := range sf {
+		if cfg.EtcdS3 {
+			fmt.Fprintf(w, "%s\t%d\t%s\n", s.Name, s.Size, s.CreatedAt.Format(time.RFC3339))
+		} else {
+			fmt.Fprintf(w, "%s\t%s\t%d\t%s\n", s.Name, s.Location, s.Size, s.CreatedAt.Format(time.RFC3339))
+		}
+	}
+
+	return nil
+}

pkg/etcd/etcd.go

@@ -871,9 +871,9 @@ type s3Config struct {
 	Folder        string `json:"folder,omitempty"`
 }
 
-// snapshotFile represents a single snapshot and it's
+// SnapshotFile represents a single snapshot and it's
 // metadata.
-type snapshotFile struct {
+type SnapshotFile struct {
 	Name string `json:"name"`
 	// Location contains the full path of the snapshot. For
 	// local paths, the location will be prefixed with "file://".
@@ -887,8 +887,8 @@ type snapshotFile struct {
 // listSnapshots provides a list of the currently stored
 // snapshots on disk or in S3 along with their relevant
 // metadata.
-func (e *ETCD) listSnapshots(ctx context.Context, snapshotDir string) ([]snapshotFile, error) {
-	var snapshots []snapshotFile
+func (e *ETCD) listSnapshots(ctx context.Context, snapshotDir string) ([]SnapshotFile, error) {
+	var snapshots []SnapshotFile
 
 	if e.config.EtcdS3 {
 		ctx, cancel := context.WithCancel(ctx)
@@ -913,7 +913,7 @@ func (e *ETCD) listSnapshots(ctx context.Context, snapshotDir string) ([]snapsho
 				return nil, err
 			}
 
-			snapshots = append(snapshots, snapshotFile{
+			snapshots = append(snapshots, SnapshotFile{
 				Name:     filepath.Base(obj.Key),
 				NodeName: "s3",
 				CreatedAt: &metav1.Time{
@@ -942,7 +942,7 @@ func (e *ETCD) listSnapshots(ctx context.Context, snapshotDir string) ([]snapsho
 	nodeName := os.Getenv("NODE_NAME")
 
 	for _, f := range files {
-		snapshots = append(snapshots, snapshotFile{
+		snapshots = append(snapshots, SnapshotFile{
 			Name:     f.Name(),
 			Location: "file://" + filepath.Join(snapshotDir, f.Name()),
 			NodeName: nodeName,
@@ -970,6 +970,17 @@ func (e *ETCD) initS3IfNil(ctx context.Context) error {
 	return nil
 }
 
+// ListSnapshots is an exported wrapper method that wraps an
+// unexported method of the same name.
+func (e *ETCD) ListSnapshots(ctx context.Context) ([]SnapshotFile, error) {
+	snapshotDir, err := snapshotDir(e.config)
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to get the snapshot dir")
+	}
+
+	return e.listSnapshots(ctx, snapshotDir)
+}
+
 // deleteSnapshots removes the given snapshots from
 // either local storage or S3.
 func (e *ETCD) DeleteSnapshots(ctx context.Context, snapshots []string) error {
@@ -1051,7 +1062,7 @@ func (e *ETCD) DeleteSnapshots(ctx context.Context, snapshots []string) error {
 }
 
 // updateSnapshotData populates the given map with the contents of the given slice.
-func updateSnapshotData(data map[string]string, snapshotFiles []snapshotFile) error {
+func updateSnapshotData(data map[string]string, snapshotFiles []SnapshotFile) error {
 	for _, v := range snapshotFiles {
 		b, err := json.Marshal(v)
 		if err != nil {
@@ -1106,14 +1117,14 @@ func (e *ETCD) StoreSnapshotData(ctx context.Context) error {
 		}
 
 		if snapshotConfigMap.Data == nil {
-			snapshotConfigMap.Data = make(map[string]string, 0)
+			snapshotConfigMap.Data = make(map[string]string)
 		}
 
 		nodeName := os.Getenv("NODE_NAME")
 
 		// remove entries for this node only
 		for k, v := range snapshotConfigMap.Data {
-			var sf snapshotFile
+			var sf SnapshotFile
 			if err := json.Unmarshal([]byte(v), &sf); err != nil {
 				return err
 			}