lib/snapshot: move Time, Validate and NewName into lib/snapshot/snapshotutil package

This allows removing importing unneeded command-line flags into binaries, which import lib/storage,
which, in turn, was importing lib/snapshot in order to use Time, Validate and NewName functions.

This is a follow-up for 83e55456e2

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5738

app/vmbackup/main.go

@@ -20,6 +20,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/pushmetrics"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/snapshot"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/snapshot/snapshotutil"
 )
 
 var (
@@ -169,7 +170,7 @@ See the docs at https://docs.victoriametrics.com/vmbackup.html .
 }
 
 func newSrcFS() (*fslocal.FS, error) {
-	if err := snapshot.Validate(*snapshotName); err != nil {
+	if err := snapshotutil.Validate(*snapshotName); err != nil {
 		return nil, fmt.Errorf("invalid -snapshotName=%q: %w", *snapshotName, err)
 	}
 	snapshotPath := filepath.Join(*storageDataPath, "snapshots", *snapshotName)

lib/backup/actions/backup.go

@@ -13,7 +13,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/backup/fslocal"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/backup/fsnil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/snapshot"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/snapshot/snapshotutil"
 	"github.com/VictoriaMetrics/metrics"
 )
 
@@ -87,7 +87,7 @@ func (b *Backup) Run() error {
 
 func storeMetadata(src *fslocal.FS, dst common.RemoteFS) error {
 	snapshotName := filepath.Base(src.Dir)
-	snapshotTime, err := snapshot.Time(snapshotName)
+	snapshotTime, err := snapshotutil.Time(snapshotName)
 	if err != nil {
 		return fmt.Errorf("cannot decode snapshot name %q: %w", snapshotName, err)
 	}

lib/snapshot/snapshot.go

@@ -8,17 +8,11 @@ import (
 	"io"
 	"net/http"
 	"net/url"
-	"regexp"
-	"strings"
-	"sync/atomic"
-	"time"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httputils"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 )
 
-var snapshotNameRegexp = regexp.MustCompile(`^[0-9]{14}-[0-9A-Fa-f]+$`)
-
 var (
 	tlsInsecureSkipVerify = flag.Bool("snapshot.tlsInsecureSkipVerify", false, "Whether to skip tls verification when connecting to -snapshotCreateURL")
 	tlsCertFile           = flag.String("snapshot.tlsCertFile", "", "Optional path to client-side TLS certificate file to use when connecting to -snapshotCreateURL")
@@ -119,37 +113,3 @@ func Delete(deleteSnapshotURL string, snapshotName string) error {
 	}
 	return fmt.Errorf("Unkown status: %v", snap.Status)
 }
-
-// Validate validates the snapshotName
-func Validate(snapshotName string) error {
-	_, err := Time(snapshotName)
-	return err
-}
-
-// Time returns snapshot creation time from the given snapshotName
-func Time(snapshotName string) (time.Time, error) {
-	if !snapshotNameRegexp.MatchString(snapshotName) {
-		return time.Time{}, fmt.Errorf("unexpected snapshot name=%q; it must match %q regexp", snapshotName, snapshotNameRegexp.String())
-	}
-	n := strings.IndexByte(snapshotName, '-')
-	if n < 0 {
-		logger.Panicf("BUG: cannot find `-` in snapshotName=%q", snapshotName)
-	}
-	s := snapshotName[:n]
-	t, err := time.Parse("20060102150405", s)
-	if err != nil {
-		return time.Time{}, fmt.Errorf("unexpected timestamp=%q in snapshot name: %w; it must match YYYYMMDDhhmmss pattern", s, err)
-	}
-	return t, nil
-}
-
-// NewName returns new name for new snapshot
-func NewName() string {
-	return fmt.Sprintf("%s-%08X", time.Now().UTC().Format("20060102150405"), nextSnapshotIdx())
-}
-
-func nextSnapshotIdx() uint64 {
-	return atomic.AddUint64(&snapshotIdx, 1)
-}
-
-var snapshotIdx = uint64(time.Now().UnixNano())

lib/snapshot/snapshot_test.go

@@ -104,54 +104,3 @@ func TestDeleteSnapshotFailed(t *testing.T) {
 		t.Fatalf("Snapshot should have failed, got: %v", err)
 	}
 }
-
-func Test_Validate(t *testing.T) {
-	tests := []struct {
-		name         string
-		snapshotName string
-		want         bool
-	}{
-		{
-			name:         "empty snapshot name",
-			snapshotName: "",
-			want:         false,
-		},
-		{
-			name:         "short snapshot name",
-			snapshotName: "",
-			want:         false,
-		},
-		{
-			name:         "short first part of the snapshot name",
-			snapshotName: "2022050312163-16EB56ADB4110CF2",
-			want:         false,
-		},
-		{
-			name:         "short second part of the snapshot name",
-			snapshotName: "20220503121638-16EB56ADB4110CF",
-			want:         true,
-		},
-		{
-			name:         "correct snapshot name",
-			snapshotName: "20220503121638-16EB56ADB4110CF2",
-			want:         true,
-		},
-		{
-			name:         "invalid time part snapshot name",
-			snapshotName: "00000000000000-16EB56ADB4110CF2",
-			want:         false,
-		},
-		{
-			name:         "not enough parts of the snapshot name",
-			snapshotName: "2022050312163816EB56ADB4110CF2",
-			want:         false,
-		},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			if err := Validate(tt.snapshotName); (err == nil) != tt.want {
-				t.Errorf("checkSnapshotName() = %v, want %v", err, tt.want)
-			}
-		})
-	}
-}

lib/snapshot/snapshotutil/snapshotutil.go

@@ -0,0 +1,47 @@
+package snapshotutil
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+	"sync/atomic"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+)
+
+var snapshotNameRegexp = regexp.MustCompile(`^[0-9]{14}-[0-9A-Fa-f]+$`)
+
+// Validate validates the snapshotName
+func Validate(snapshotName string) error {
+	_, err := Time(snapshotName)
+	return err
+}
+
+// Time returns snapshot creation time from the given snapshotName
+func Time(snapshotName string) (time.Time, error) {
+	if !snapshotNameRegexp.MatchString(snapshotName) {
+		return time.Time{}, fmt.Errorf("unexpected snapshot name=%q; it must match %q regexp", snapshotName, snapshotNameRegexp.String())
+	}
+	n := strings.IndexByte(snapshotName, '-')
+	if n < 0 {
+		logger.Panicf("BUG: cannot find `-` in snapshotName=%q", snapshotName)
+	}
+	s := snapshotName[:n]
+	t, err := time.Parse("20060102150405", s)
+	if err != nil {
+		return time.Time{}, fmt.Errorf("unexpected timestamp=%q in snapshot name: %w; it must match YYYYMMDDhhmmss pattern", s, err)
+	}
+	return t, nil
+}
+
+// NewName returns new name for new snapshot
+func NewName() string {
+	return fmt.Sprintf("%s-%08X", time.Now().UTC().Format("20060102150405"), nextSnapshotIdx())
+}
+
+func nextSnapshotIdx() uint64 {
+	return atomic.AddUint64(&snapshotIdx, 1)
+}
+
+var snapshotIdx = uint64(time.Now().UnixNano())

lib/snapshot/snapshotutil/snapshotutil_test.go

@@ -0,0 +1,56 @@
+package snapshotutil
+
+import (
+	"testing"
+)
+
+func Test_Validate(t *testing.T) {
+	tests := []struct {
+		name         string
+		snapshotName string
+		want         bool
+	}{
+		{
+			name:         "empty snapshot name",
+			snapshotName: "",
+			want:         false,
+		},
+		{
+			name:         "short snapshot name",
+			snapshotName: "",
+			want:         false,
+		},
+		{
+			name:         "short first part of the snapshot name",
+			snapshotName: "2022050312163-16EB56ADB4110CF2",
+			want:         false,
+		},
+		{
+			name:         "short second part of the snapshot name",
+			snapshotName: "20220503121638-16EB56ADB4110CF",
+			want:         true,
+		},
+		{
+			name:         "correct snapshot name",
+			snapshotName: "20220503121638-16EB56ADB4110CF2",
+			want:         true,
+		},
+		{
+			name:         "invalid time part snapshot name",
+			snapshotName: "00000000000000-16EB56ADB4110CF2",
+			want:         false,
+		},
+		{
+			name:         "not enough parts of the snapshot name",
+			snapshotName: "2022050312163816EB56ADB4110CF2",
+			want:         false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if err := Validate(tt.snapshotName); (err == nil) != tt.want {
+				t.Errorf("checkSnapshotName() = %v, want %v", err, tt.want)
+			}
+		})
+	}
+}

lib/storage/storage.go

@@ -25,7 +25,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/memory"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/querytracer"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/snapshot"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/snapshot/snapshotutil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/timeutil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/uint64set"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/workingsetcache"
@@ -342,7 +342,7 @@ func (s *Storage) CreateSnapshot(deadline uint64) (string, error) {
 		}
 	}()
 
-	snapshotName := snapshot.NewName()
+	snapshotName := snapshotutil.NewName()
 	srcDir := s.path
 	dstDir := filepath.Join(srcDir, snapshotsDirname, snapshotName)
 	fs.MustMkdirFailIfExist(dstDir)
@@ -409,7 +409,7 @@ func (s *Storage) ListSnapshots() ([]string, error) {
 	}
 	snapshotNames := make([]string, 0, len(fnames))
 	for _, fname := range fnames {
-		if err := snapshot.Validate(fname); err != nil {
+		if err := snapshotutil.Validate(fname); err != nil {
 			continue
 		}
 		snapshotNames = append(snapshotNames, fname)
@@ -420,7 +420,7 @@ func (s *Storage) ListSnapshots() ([]string, error) {
 
 // DeleteSnapshot deletes the given snapshot.
 func (s *Storage) DeleteSnapshot(snapshotName string) error {
-	if err := snapshot.Validate(snapshotName); err != nil {
+	if err := snapshotutil.Validate(snapshotName); err != nil {
 		return fmt.Errorf("invalid snapshotName %q: %w", snapshotName, err)
 	}
 	snapshotPath := filepath.Join(s.path, snapshotsDirname, snapshotName)
@@ -446,7 +446,7 @@ func (s *Storage) DeleteStaleSnapshots(maxAge time.Duration) error {
 	}
 	expireDeadline := time.Now().UTC().Add(-maxAge)
 	for _, snapshotName := range list {
-		t, err := snapshot.Time(snapshotName)
+		t, err := snapshotutil.Time(snapshotName)
 		if err != nil {
 			return fmt.Errorf("cannot parse snapshot date from %q: %w", snapshotName, err)
 		}