Merge pull request #473 from ahrtr/revert_meta_20230426

Migrate `surgery revert-meta-page` to cobra style command

cmd/bbolt/command_surgery_cobra.go

@@ -30,12 +30,54 @@ func newSurgeryCobraCommand() *cobra.Command {
 		Short: "surgery related commands",
 	}
 
+	surgeryCmd.AddCommand(newSurgeryRevertMetaPageCommand())
 	surgeryCmd.AddCommand(newSurgeryClearPageElementsCommand())
 	surgeryCmd.AddCommand(newSurgeryFreelistCommand())
 
 	return surgeryCmd
 }
 
+func newSurgeryRevertMetaPageCommand() *cobra.Command {
+	revertMetaPageCmd := &cobra.Command{
+		Use:   "revert-meta-page <bbolt-file> [options]",
+		Short: "Revert the meta page to revert the changes performed by the latest transaction",
+		Args: func(cmd *cobra.Command, args []string) error {
+			if len(args) == 0 {
+				return errors.New("db file path not provided")
+			}
+			if len(args) > 1 {
+				return errors.New("too many arguments")
+			}
+			return nil
+		},
+		RunE: surgeryRevertMetaPageFunc,
+	}
+
+	revertMetaPageCmd.Flags().StringVar(&surgeryTargetDBFilePath, "output", "", "path to the target db file")
+
+	return revertMetaPageCmd
+}
+
+func surgeryRevertMetaPageFunc(cmd *cobra.Command, args []string) error {
+	srcDBPath := args[0]
+
+	if err := checkDBPaths(srcDBPath, surgeryTargetDBFilePath); err != nil {
+		return err
+	}
+
+	if err := common.CopyFile(srcDBPath, surgeryTargetDBFilePath); err != nil {
+		return fmt.Errorf("[revert-meta-page] copy file failed: %w", err)
+	}
+
+	if err := surgeon.RevertMetaPage(surgeryTargetDBFilePath); err != nil {
+		return fmt.Errorf("revert-meta-page command failed: %w", err)
+	}
+
+	fmt.Fprintln(os.Stdout, "The meta page is reverted.")
+
+	return nil
+}
+
 func newSurgeryClearPageElementsCommand() *cobra.Command {
 	clearElementCmd := &cobra.Command{
 		Use:   "clear-page-elements <bbolt-file> [options]",
@@ -210,3 +252,18 @@ func readMetaPage(path string) (*common.Meta, error) {
 	}
 	return common.LoadPageMeta(buf), nil
 }
+
+func checkDBPaths(srcPath, dstPath string) error {
+	_, err := os.Stat(srcPath)
+	if os.IsNotExist(err) {
+		return fmt.Errorf("source database file %q doesn't exist", srcPath)
+	} else if err != nil {
+		return fmt.Errorf("failed to open source database file %q: %v", srcPath, err)
+	}
+
+	if dstPath == "" {
+		return fmt.Errorf("output database path wasn't given, specify output database file path with --output option")
+	}
+
+	return nil
+}

cmd/bbolt/command_surgery_cobra_test.go

@@ -2,6 +2,7 @@ package main_test
 
 import (
 	"fmt"
+	"os"
 	"path/filepath"
 	"testing"
 
@@ -15,6 +16,51 @@ import (
 	"go.etcd.io/bbolt/internal/guts_cli"
 )
 
+func TestSurgery_RevertMetaPage(t *testing.T) {
+	pageSize := 4096
+	db := btesting.MustCreateDBWithOption(t, &bolt.Options{PageSize: pageSize})
+	srcPath := db.Path()
+
+	defer requireDBNoChange(t, dbData(t, db.Path()), db.Path())
+
+	srcFile, err := os.Open(srcPath)
+	require.NoError(t, err)
+	defer srcFile.Close()
+
+	// Read both meta0 and meta1 from srcFile
+	srcBuf0 := readPage(t, srcPath, 0, pageSize)
+	srcBuf1 := readPage(t, srcPath, 1, pageSize)
+	meta0Page := common.LoadPageMeta(srcBuf0)
+	meta1Page := common.LoadPageMeta(srcBuf1)
+
+	// Get the non-active meta page
+	nonActiveSrcBuf := srcBuf0
+	nonActiveMetaPageId := 0
+	if meta0Page.Txid() > meta1Page.Txid() {
+		nonActiveSrcBuf = srcBuf1
+		nonActiveMetaPageId = 1
+	}
+	t.Logf("non active meta page id: %d", nonActiveMetaPageId)
+
+	// revert the meta page
+	rootCmd := main.NewRootCommand()
+	output := filepath.Join(t.TempDir(), "db")
+	rootCmd.SetArgs([]string{
+		"surgery", "revert-meta-page", srcPath,
+		"--output", output,
+	})
+	err = rootCmd.Execute()
+	require.NoError(t, err)
+
+	// read both meta0 and meta1 from dst file
+	dstBuf0 := readPage(t, output, 0, pageSize)
+	dstBuf1 := readPage(t, output, 1, pageSize)
+
+	// check result. Note we should skip the page ID
+	assert.Equal(t, pageDataWithoutPageId(nonActiveSrcBuf), pageDataWithoutPageId(dstBuf0))
+	assert.Equal(t, pageDataWithoutPageId(nonActiveSrcBuf), pageDataWithoutPageId(dstBuf1))
+}
+
 func TestSurgery_ClearPageElements_Without_Overflow(t *testing.T) {
 	testCases := []struct {
 		name                 string

cmd/bbolt/surgery_commands.go

@@ -40,8 +40,6 @@ func (cmd *surgeryCommand) Run(args ...string) error {
 	case "help":
 		fmt.Fprintln(cmd.Stderr, cmd.Usage())
 		return ErrUsage
-	case "revert-meta-page":
-		return newRevertMetaPageCommand(cmd).Run(args[1:]...)
 	case "copy-page":
 		return newCopyPageCommand(cmd).Run(args[1:]...)
 	case "clear-page":
@@ -90,56 +88,6 @@ Use "bbolt surgery [command] -h" for more information about a command.
 `, "\n")
 }
 
-// revertMetaPageCommand represents the "surgery revert-meta-page" command execution.
-type revertMetaPageCommand struct {
-	*surgeryCommand
-}
-
-// newRevertMetaPageCommand returns a revertMetaPageCommand.
-func newRevertMetaPageCommand(m *surgeryCommand) *revertMetaPageCommand {
-	c := &revertMetaPageCommand{}
-	c.surgeryCommand = m
-	return c
-}
-
-// Run executes the command.
-func (cmd *revertMetaPageCommand) Run(args ...string) error {
-	// Parse flags.
-	fs := flag.NewFlagSet("", flag.ContinueOnError)
-	help := fs.Bool("h", false, "")
-	if err := fs.Parse(args); err != nil {
-		return err
-	} else if *help {
-		fmt.Fprintln(cmd.Stderr, cmd.Usage())
-		return ErrUsage
-	}
-
-	if err := cmd.parsePathsAndCopyFile(fs); err != nil {
-		return fmt.Errorf("revertMetaPageCommand failed to parse paths and copy file: %w", err)
-	}
-
-	// revert the meta page
-	if err := surgeon.RevertMetaPage(cmd.dstPath); err != nil {
-		return fmt.Errorf("revertMetaPageCommand failed: %w", err)
-	}
-
-	fmt.Fprintln(cmd.Stdout, "The meta page is reverted.")
-	return nil
-}
-
-// Usage returns the help message.
-func (cmd *revertMetaPageCommand) Usage() string {
-	return strings.TrimLeft(`
-usage: bolt surgery revert-meta-page SRC DST
-
-RevertMetaPage copies the database file at SRC to a newly created database
-file at DST. Afterwards, it reverts the meta page on the newly created
-database at DST.
-
-The original database is left untouched.
-`, "\n")
-}
-
 // copyPageCommand represents the "surgery copy-page" command execution.
 type copyPageCommand struct {
 	*surgeryCommand

cmd/bbolt/surgery_commands_test.go

@@ -14,47 +14,6 @@ import (
 	"go.etcd.io/bbolt/internal/common"
 )
 
-func TestSurgery_RevertMetaPage(t *testing.T) {
-	pageSize := 4096
-	db := btesting.MustCreateDBWithOption(t, &bolt.Options{PageSize: pageSize})
-	srcPath := db.Path()
-
-	defer requireDBNoChange(t, dbData(t, db.Path()), db.Path())
-
-	srcFile, err := os.Open(srcPath)
-	require.NoError(t, err)
-	defer srcFile.Close()
-
-	// Read both meta0 and meta1 from srcFile
-	srcBuf0 := readPage(t, srcPath, 0, pageSize)
-	srcBuf1 := readPage(t, srcPath, 1, pageSize)
-	meta0Page := common.LoadPageMeta(srcBuf0)
-	meta1Page := common.LoadPageMeta(srcBuf1)
-
-	// Get the non-active meta page
-	nonActiveSrcBuf := srcBuf0
-	nonActiveMetaPageId := 0
-	if meta0Page.Txid() > meta1Page.Txid() {
-		nonActiveSrcBuf = srcBuf1
-		nonActiveMetaPageId = 1
-	}
-	t.Logf("non active meta page id: %d", nonActiveMetaPageId)
-
-	// revert the meta page
-	dstPath := filepath.Join(t.TempDir(), "dstdb")
-	m := NewMain()
-	err = m.Run("surgery", "revert-meta-page", srcPath, dstPath)
-	require.NoError(t, err)
-
-	// read both meta0 and meta1 from dst file
-	dstBuf0 := readPage(t, dstPath, 0, pageSize)
-	dstBuf1 := readPage(t, dstPath, 1, pageSize)
-
-	// check result. Note we should skip the page ID
-	assert.Equal(t, pageDataWithoutPageId(nonActiveSrcBuf), pageDataWithoutPageId(dstBuf0))
-	assert.Equal(t, pageDataWithoutPageId(nonActiveSrcBuf), pageDataWithoutPageId(dstBuf1))
-}
-
 func TestSurgery_CopyPage(t *testing.T) {
 	pageSize := 4096
 	db := btesting.MustCreateDBWithOption(t, &bolt.Options{PageSize: pageSize})