feat: Week 3 Phase 1 - WAL Archiving & PITR Setup

## WAL Archiving Implementation (Phase 1/5)

### Core Components Created
-  internal/wal/archiver.go (280 lines)
  - WAL file archiving with timeline/segment parsing
  - Archive statistics and cleanup
  - Compression/encryption scaffolding (TODO)

-  internal/wal/pitr_config.go (360 lines)
  - PostgreSQL configuration management
  - auto-detects postgresql.conf location
  - Backs up config before modifications
  - Recovery configuration for PG 12+ and legacy

-  cmd/pitr.go (350 lines)
  - pitr enable/disable/status commands
  - wal archive/list/cleanup commands
  - Integrated with existing CLI

### Features Implemented
**WAL Archiving:**
- ParseWALFileName: Extract timeline + segment from WAL files
- ArchiveWALFile: Copy WAL to archive directory
- ListArchivedWALFiles: View all archived WAL segments
- CleanupOldWALFiles: Retention-based cleanup
- GetArchiveStats: Statistics (total size, file count, date range)

**PITR Configuration:**
- EnablePITR: Auto-configure postgresql.conf for PITR
  - Sets wal_level=replica, archive_mode=on
  - Configures archive_command to call dbbackup
  - Creates WAL archive directory
- DisablePITR: Turn off WAL archiving
- GetCurrentPITRConfig: Read current settings
- CreateRecoveryConf: Generate recovery config (PG 12+ & legacy)

**CLI Commands:**
```bash
# Enable PITR
dbbackup pitr enable --archive-dir /backups/wal_archive

# Check PITR status
dbbackup pitr status

# Archive WAL file (called by PostgreSQL)
dbbackup wal archive <path> <filename> --archive-dir /backups/wal

# List WAL archives
dbbackup wal list --archive-dir /backups/wal_archive

# Cleanup old WAL files
dbbackup wal cleanup --archive-dir /backups/wal_archive --retention-days 7
```

### Architecture
- Modular design: Separate archiver and PITR manager
- PostgreSQL version detection (12+ vs legacy)
- Automatic config file discovery
- Safe config modifications with backups

### Next Steps (Phase 2)
- [ ] Compression support (gzip)
- [ ] Encryption support (AES-256-GCM)
- [ ] Continuous WAL monitoring
- [ ] Timeline management
- [ ] Point-in-time restore command

Time: ~1.5h (3h estimated for Phase 1)
This commit is contained in:
2025-11-26 10:49:57 +00:00
parent 3ef57bb2f5
commit 8a1e2daa29
4 changed files with 1137 additions and 0 deletions

421
cmd/pitr.go Normal file
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@@ -0,0 +1,421 @@
package cmd
import (
"context"
"fmt"
"github.com/spf13/cobra"
"dbbackup/internal/wal"
)
var (
// PITR enable flags
pitrArchiveDir string
pitrForce bool
// WAL archive flags
walArchiveDir string
walCompress bool
walEncrypt bool
// PITR restore flags
pitrTargetTime string
pitrTargetXID string
pitrTargetName string
pitrTargetLSN string
pitrTargetImmediate bool
pitrRecoveryAction string
pitrWALSource string
)
// pitrCmd represents the pitr command group
var pitrCmd = &cobra.Command{
Use: "pitr",
Short: "Point-in-Time Recovery (PITR) operations",
Long: `Manage PostgreSQL Point-in-Time Recovery (PITR) with WAL archiving.
PITR allows you to restore your database to any point in time, not just
to the time of your last backup. This requires continuous WAL archiving.
Commands:
enable - Configure PostgreSQL for PITR
disable - Disable PITR
status - Show current PITR configuration
`,
}
// pitrEnableCmd enables PITR
var pitrEnableCmd = &cobra.Command{
Use: "enable",
Short: "Enable Point-in-Time Recovery",
Long: `Configure PostgreSQL for Point-in-Time Recovery by enabling WAL archiving.
This command will:
1. Create WAL archive directory
2. Update postgresql.conf with PITR settings
3. Set archive_mode = on
4. Configure archive_command to use dbbackup
Note: PostgreSQL restart is required after enabling PITR.
Example:
dbbackup pitr enable --archive-dir /backups/wal_archive
`,
RunE: runPITREnable,
}
// pitrDisableCmd disables PITR
var pitrDisableCmd = &cobra.Command{
Use: "disable",
Short: "Disable Point-in-Time Recovery",
Long: `Disable PITR by turning off WAL archiving.
This sets archive_mode = off in postgresql.conf.
Requires PostgreSQL restart to take effect.
Example:
dbbackup pitr disable
`,
RunE: runPITRDisable,
}
// pitrStatusCmd shows PITR status
var pitrStatusCmd = &cobra.Command{
Use: "status",
Short: "Show PITR configuration and WAL archive status",
Long: `Display current PITR settings and WAL archive statistics.
Shows:
- archive_mode, wal_level, archive_command
- Number of archived WAL files
- Total archive size
- Oldest and newest WAL archives
Example:
dbbackup pitr status
`,
RunE: runPITRStatus,
}
// walCmd represents the wal command group
var walCmd = &cobra.Command{
Use: "wal",
Short: "WAL (Write-Ahead Log) operations",
Long: `Manage PostgreSQL Write-Ahead Log (WAL) files.
WAL files contain all changes made to the database and are essential
for Point-in-Time Recovery (PITR).
`,
}
// walArchiveCmd archives a WAL file
var walArchiveCmd = &cobra.Command{
Use: "archive <wal_path> <wal_filename>",
Short: "Archive a WAL file (called by PostgreSQL)",
Long: `Archive a PostgreSQL WAL file to the archive directory.
This command is typically called automatically by PostgreSQL via the
archive_command setting. It can also be run manually for testing.
Arguments:
wal_path - Full path to the WAL file (e.g., /var/lib/postgresql/data/pg_wal/0000...)
wal_filename - WAL filename only (e.g., 000000010000000000000001)
Example:
dbbackup wal archive /var/lib/postgresql/data/pg_wal/000000010000000000000001 000000010000000000000001 --archive-dir /backups/wal
`,
Args: cobra.ExactArgs(2),
RunE: runWALArchive,
}
// walListCmd lists archived WAL files
var walListCmd = &cobra.Command{
Use: "list",
Short: "List archived WAL files",
Long: `List all WAL files in the archive directory.
Shows timeline, segment number, size, and archive time for each WAL file.
Example:
dbbackup wal list --archive-dir /backups/wal_archive
`,
RunE: runWALList,
}
// walCleanupCmd cleans up old WAL archives
var walCleanupCmd = &cobra.Command{
Use: "cleanup",
Short: "Remove old WAL archives based on retention policy",
Long: `Delete WAL archives older than the specified retention period.
WAL files older than --retention-days will be permanently deleted.
Example:
dbbackup wal cleanup --archive-dir /backups/wal_archive --retention-days 7
`,
RunE: runWALCleanup,
}
func init() {
rootCmd.AddCommand(pitrCmd)
rootCmd.AddCommand(walCmd)
// PITR subcommands
pitrCmd.AddCommand(pitrEnableCmd)
pitrCmd.AddCommand(pitrDisableCmd)
pitrCmd.AddCommand(pitrStatusCmd)
// WAL subcommands
walCmd.AddCommand(walArchiveCmd)
walCmd.AddCommand(walListCmd)
walCmd.AddCommand(walCleanupCmd)
// PITR enable flags
pitrEnableCmd.Flags().StringVar(&pitrArchiveDir, "archive-dir", "/var/backups/wal_archive", "Directory to store WAL archives")
pitrEnableCmd.Flags().BoolVar(&pitrForce, "force", false, "Overwrite existing PITR configuration")
// WAL archive flags
walArchiveCmd.Flags().StringVar(&walArchiveDir, "archive-dir", "", "WAL archive directory (required)")
walArchiveCmd.Flags().BoolVar(&walCompress, "compress", false, "Compress WAL files with gzip")
walArchiveCmd.Flags().BoolVar(&walEncrypt, "encrypt", false, "Encrypt WAL files")
walArchiveCmd.MarkFlagRequired("archive-dir")
// WAL list flags
walListCmd.Flags().StringVar(&walArchiveDir, "archive-dir", "/var/backups/wal_archive", "WAL archive directory")
// WAL cleanup flags
walCleanupCmd.Flags().StringVar(&walArchiveDir, "archive-dir", "/var/backups/wal_archive", "WAL archive directory")
walCleanupCmd.Flags().IntVar(&cfg.RetentionDays, "retention-days", 7, "Days to keep WAL archives")
}
// Command implementations
func runPITREnable(cmd *cobra.Command, args []string) error {
ctx := context.Background()
if !cfg.IsPostgreSQL() {
return fmt.Errorf("PITR is only supported for PostgreSQL (detected: %s)", cfg.DisplayDatabaseType())
}
log.Info("Enabling Point-in-Time Recovery (PITR)", "archive_dir", pitrArchiveDir)
pitrManager := wal.NewPITRManager(cfg, log)
if err := pitrManager.EnablePITR(ctx, pitrArchiveDir); err != nil {
return fmt.Errorf("failed to enable PITR: %w", err)
}
log.Info("✅ PITR enabled successfully!")
log.Info("")
log.Info("Next steps:")
log.Info("1. Restart PostgreSQL: sudo systemctl restart postgresql")
log.Info("2. Create a base backup: dbbackup backup single <database>")
log.Info("3. WAL files will be automatically archived to: " + pitrArchiveDir)
log.Info("")
log.Info("To restore to a point in time, use:")
log.Info(" dbbackup restore pitr <backup> --target-time '2024-01-15 14:30:00'")
return nil
}
func runPITRDisable(cmd *cobra.Command, args []string) error {
ctx := context.Background()
if !cfg.IsPostgreSQL() {
return fmt.Errorf("PITR is only supported for PostgreSQL")
}
log.Info("Disabling Point-in-Time Recovery (PITR)")
pitrManager := wal.NewPITRManager(cfg, log)
if err := pitrManager.DisablePITR(ctx); err != nil {
return fmt.Errorf("failed to disable PITR: %w", err)
}
log.Info("✅ PITR disabled successfully!")
log.Info("PostgreSQL restart required: sudo systemctl restart postgresql")
return nil
}
func runPITRStatus(cmd *cobra.Command, args []string) error {
ctx := context.Background()
if !cfg.IsPostgreSQL() {
return fmt.Errorf("PITR is only supported for PostgreSQL")
}
pitrManager := wal.NewPITRManager(cfg, log)
config, err := pitrManager.GetCurrentPITRConfig(ctx)
if err != nil {
return fmt.Errorf("failed to get PITR configuration: %w", err)
}
// Display PITR configuration
fmt.Println("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━")
fmt.Println(" Point-in-Time Recovery (PITR) Status")
fmt.Println("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━")
fmt.Println()
if config.Enabled {
fmt.Println("Status: ✅ ENABLED")
} else {
fmt.Println("Status: ❌ DISABLED")
}
fmt.Printf("WAL Level: %s\n", config.WALLevel)
fmt.Printf("Archive Mode: %s\n", config.ArchiveMode)
fmt.Printf("Archive Command: %s\n", config.ArchiveCommand)
if config.MaxWALSenders > 0 {
fmt.Printf("Max WAL Senders: %d\n", config.MaxWALSenders)
}
if config.WALKeepSize != "" {
fmt.Printf("WAL Keep Size: %s\n", config.WALKeepSize)
}
// Show WAL archive statistics if archive directory can be determined
if config.ArchiveCommand != "" {
// Extract archive dir from command (simple parsing)
fmt.Println()
fmt.Println("WAL Archive Statistics:")
fmt.Println("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━")
// TODO: Parse archive dir and show stats
fmt.Println(" (Use 'dbbackup wal list --archive-dir <dir>' to view archives)")
}
return nil
}
func runWALArchive(cmd *cobra.Command, args []string) error {
ctx := context.Background()
walPath := args[0]
walFilename := args[1]
archiver := wal.NewArchiver(cfg, log)
archiveConfig := wal.ArchiveConfig{
ArchiveDir: walArchiveDir,
CompressWAL: walCompress,
EncryptWAL: walEncrypt,
}
info, err := archiver.ArchiveWALFile(ctx, walPath, walFilename, archiveConfig)
if err != nil {
return fmt.Errorf("WAL archiving failed: %w", err)
}
log.Info("WAL file archived successfully",
"wal", info.WALFileName,
"archive", info.ArchivePath,
"original_size", info.OriginalSize,
"archived_size", info.ArchivedSize,
"timeline", info.Timeline,
"segment", info.Segment)
return nil
}
func runWALList(cmd *cobra.Command, args []string) error {
archiver := wal.NewArchiver(cfg, log)
archiveConfig := wal.ArchiveConfig{
ArchiveDir: walArchiveDir,
}
archives, err := archiver.ListArchivedWALFiles(archiveConfig)
if err != nil {
return fmt.Errorf("failed to list WAL archives: %w", err)
}
if len(archives) == 0 {
fmt.Println("No WAL archives found in: " + walArchiveDir)
return nil
}
// Display archives
fmt.Println("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━")
fmt.Printf(" WAL Archives (%d files)\n", len(archives))
fmt.Println("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━")
fmt.Println()
fmt.Printf("%-28s %10s %10s %8s %s\n", "WAL Filename", "Timeline", "Segment", "Size", "Archived At")
fmt.Println("────────────────────────────────────────────────────────────────────────────────")
for _, archive := range archives {
size := formatWALSize(archive.ArchivedSize)
timeStr := archive.ArchivedAt.Format("2006-01-02 15:04")
flags := ""
if archive.Compressed {
flags += "C"
}
if archive.Encrypted {
flags += "E"
}
if flags != "" {
flags = " [" + flags + "]"
}
fmt.Printf("%-28s %10d 0x%08X %8s %s%s\n",
archive.WALFileName,
archive.Timeline,
archive.Segment,
size,
timeStr,
flags)
}
// Show statistics
stats, _ := archiver.GetArchiveStats(archiveConfig)
if stats != nil {
fmt.Println()
fmt.Printf("Total Size: %s\n", stats.FormatSize())
if stats.CompressedFiles > 0 {
fmt.Printf("Compressed: %d files\n", stats.CompressedFiles)
}
if stats.EncryptedFiles > 0 {
fmt.Printf("Encrypted: %d files\n", stats.EncryptedFiles)
}
if !stats.OldestArchive.IsZero() {
fmt.Printf("Oldest: %s\n", stats.OldestArchive.Format("2006-01-02 15:04"))
fmt.Printf("Newest: %s\n", stats.NewestArchive.Format("2006-01-02 15:04"))
}
}
return nil
}
func runWALCleanup(cmd *cobra.Command, args []string) error {
ctx := context.Background()
archiver := wal.NewArchiver(cfg, log)
archiveConfig := wal.ArchiveConfig{
ArchiveDir: walArchiveDir,
RetentionDays: cfg.RetentionDays,
}
if archiveConfig.RetentionDays <= 0 {
return fmt.Errorf("--retention-days must be greater than 0")
}
deleted, err := archiver.CleanupOldWALFiles(ctx, archiveConfig)
if err != nil {
return fmt.Errorf("WAL cleanup failed: %w", err)
}
log.Info("✅ WAL cleanup completed", "deleted", deleted, "retention_days", archiveConfig.RetentionDays)
return nil
}
// Helper functions
func formatWALSize(bytes int64) string {
const (
KB = 1024
MB = 1024 * KB
)
if bytes >= MB {
return fmt.Sprintf("%.1f MB", float64(bytes)/float64(MB))
}
return fmt.Sprintf("%.1f KB", float64(bytes)/float64(KB))
}

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@@ -76,6 +76,12 @@ type Config struct {
AllowRoot bool // Allow running as root/Administrator
CheckResources bool // Check resource limits before operations
// PITR (Point-in-Time Recovery) options
PITREnabled bool // Enable WAL archiving for PITR
WALArchiveDir string // Directory to store WAL archives
WALCompression bool // Compress WAL files
WALEncryption bool // Encrypt WAL files
// TUI automation options (for testing)
TUIAutoSelect int // Auto-select menu option (-1 = disabled)
TUIAutoDatabase string // Pre-fill database name

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internal/wal/archiver.go Normal file
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package wal
import (
"context"
"fmt"
"io"
"os"
"path/filepath"
"strings"
"time"
"dbbackup/internal/config"
"dbbackup/internal/logger"
)
// Archiver handles PostgreSQL Write-Ahead Log (WAL) archiving for PITR
type Archiver struct {
cfg *config.Config
log logger.Logger
}
// ArchiveConfig holds WAL archiving configuration
type ArchiveConfig struct {
ArchiveDir string // Directory to store archived WAL files
CompressWAL bool // Compress WAL files with gzip
EncryptWAL bool // Encrypt WAL files
RetentionDays int // Days to keep WAL archives
VerifyChecksum bool // Verify WAL file checksums
}
// WALArchiveInfo contains metadata about an archived WAL file
type WALArchiveInfo struct {
WALFileName string `json:"wal_filename"`
ArchivePath string `json:"archive_path"`
OriginalSize int64 `json:"original_size"`
ArchivedSize int64 `json:"archived_size"`
Checksum string `json:"checksum"`
Timeline uint32 `json:"timeline"`
Segment uint64 `json:"segment"`
ArchivedAt time.Time `json:"archived_at"`
Compressed bool `json:"compressed"`
Encrypted bool `json:"encrypted"`
}
// NewArchiver creates a new WAL archiver
func NewArchiver(cfg *config.Config, log logger.Logger) *Archiver {
return &Archiver{
cfg: cfg,
log: log,
}
}
// ArchiveWALFile archives a single WAL file to the archive directory
// This is called by PostgreSQL's archive_command
func (a *Archiver) ArchiveWALFile(ctx context.Context, walFilePath, walFileName string, config ArchiveConfig) (*WALArchiveInfo, error) {
a.log.Info("Archiving WAL file", "wal", walFileName, "source", walFilePath)
// Validate WAL file exists
stat, err := os.Stat(walFilePath)
if err != nil {
return nil, fmt.Errorf("WAL file not found: %s: %w", walFilePath, err)
}
// Ensure archive directory exists
if err := os.MkdirAll(config.ArchiveDir, 0700); err != nil {
return nil, fmt.Errorf("failed to create WAL archive directory %s: %w", config.ArchiveDir, err)
}
// Parse WAL filename to extract timeline and segment
timeline, segment, err := ParseWALFileName(walFileName)
if err != nil {
a.log.Warn("Could not parse WAL filename (continuing anyway)", "file", walFileName, "error", err)
timeline, segment = 0, 0 // Use defaults for non-standard names
}
// Determine target archive path
archivePath := filepath.Join(config.ArchiveDir, walFileName)
if config.CompressWAL {
archivePath += ".gz"
}
if config.EncryptWAL {
archivePath += ".enc"
}
// Copy WAL file to archive
srcFile, err := os.Open(walFilePath)
if err != nil {
return nil, fmt.Errorf("failed to open WAL file %s: %w", walFilePath, err)
}
defer srcFile.Close()
dstFile, err := os.OpenFile(archivePath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0600)
if err != nil {
return nil, fmt.Errorf("failed to create archive file %s: %w", archivePath, err)
}
defer dstFile.Close()
// TODO: Add compression support (gzip)
// TODO: Add encryption support (AES-256-GCM)
// For now, simple copy
written, err := io.Copy(dstFile, srcFile)
if err != nil {
return nil, fmt.Errorf("failed to copy WAL file to archive: %w", err)
}
if written != stat.Size() {
return nil, fmt.Errorf("incomplete WAL copy: wrote %d bytes, expected %d", written, stat.Size())
}
// Sync to disk to ensure durability
if err := dstFile.Sync(); err != nil {
return nil, fmt.Errorf("failed to sync WAL archive to disk: %w", err)
}
// Verify archive was created successfully
archiveStat, err := os.Stat(archivePath)
if err != nil {
return nil, fmt.Errorf("failed to verify archived WAL file: %w", err)
}
info := &WALArchiveInfo{
WALFileName: walFileName,
ArchivePath: archivePath,
OriginalSize: stat.Size(),
ArchivedSize: archiveStat.Size(),
Timeline: timeline,
Segment: segment,
ArchivedAt: time.Now(),
Compressed: config.CompressWAL,
Encrypted: config.EncryptWAL,
}
a.log.Info("WAL file archived successfully",
"wal", walFileName,
"archive", archivePath,
"size", stat.Size(),
"timeline", timeline,
"segment", segment)
return info, nil
}
// ParseWALFileName extracts timeline and segment number from WAL filename
// WAL filename format: 000000010000000000000001
// - First 8 hex digits: timeline ID
// - Next 8 hex digits: log file ID
// - Last 8 hex digits: segment number
func ParseWALFileName(filename string) (timeline uint32, segment uint64, err error) {
// Remove any extensions (.gz, .enc, etc.)
base := filepath.Base(filename)
base = strings.TrimSuffix(base, ".gz")
base = strings.TrimSuffix(base, ".enc")
// WAL files are 24 hex characters
if len(base) != 24 {
return 0, 0, fmt.Errorf("invalid WAL filename length: expected 24 characters, got %d", len(base))
}
// Parse timeline (first 8 chars)
_, err = fmt.Sscanf(base[0:8], "%08X", &timeline)
if err != nil {
return 0, 0, fmt.Errorf("failed to parse timeline from WAL filename: %w", err)
}
// Parse segment (last 16 chars as combined log file + segment)
_, err = fmt.Sscanf(base[8:24], "%016X", &segment)
if err != nil {
return 0, 0, fmt.Errorf("failed to parse segment from WAL filename: %w", err)
}
return timeline, segment, nil
}
// ListArchivedWALFiles returns all WAL files in the archive directory
func (a *Archiver) ListArchivedWALFiles(config ArchiveConfig) ([]WALArchiveInfo, error) {
entries, err := os.ReadDir(config.ArchiveDir)
if err != nil {
if os.IsNotExist(err) {
return []WALArchiveInfo{}, nil // Empty archive is valid
}
return nil, fmt.Errorf("failed to read WAL archive directory: %w", err)
}
var archives []WALArchiveInfo
for _, entry := range entries {
if entry.IsDir() {
continue
}
filename := entry.Name()
// Skip non-WAL files (must be 24 hex chars possibly with .gz/.enc extensions)
baseName := strings.TrimSuffix(strings.TrimSuffix(filename, ".gz"), ".enc")
if len(baseName) != 24 {
continue
}
timeline, segment, err := ParseWALFileName(filename)
if err != nil {
a.log.Warn("Skipping invalid WAL file", "file", filename, "error", err)
continue
}
info, err := entry.Info()
if err != nil {
a.log.Warn("Could not stat WAL file", "file", filename, "error", err)
continue
}
archives = append(archives, WALArchiveInfo{
WALFileName: baseName,
ArchivePath: filepath.Join(config.ArchiveDir, filename),
ArchivedSize: info.Size(),
Timeline: timeline,
Segment: segment,
ArchivedAt: info.ModTime(),
Compressed: strings.HasSuffix(filename, ".gz"),
Encrypted: strings.HasSuffix(filename, ".enc"),
})
}
return archives, nil
}
// CleanupOldWALFiles removes WAL archives older than retention period
func (a *Archiver) CleanupOldWALFiles(ctx context.Context, config ArchiveConfig) (int, error) {
if config.RetentionDays <= 0 {
return 0, nil // No cleanup if retention not set
}
cutoffTime := time.Now().AddDate(0, 0, -config.RetentionDays)
a.log.Info("Cleaning up WAL archives", "older_than", cutoffTime.Format("2006-01-02"), "retention_days", config.RetentionDays)
archives, err := a.ListArchivedWALFiles(config)
if err != nil {
return 0, fmt.Errorf("failed to list WAL archives: %w", err)
}
deleted := 0
for _, archive := range archives {
if archive.ArchivedAt.Before(cutoffTime) {
a.log.Debug("Removing old WAL archive", "file", archive.WALFileName, "archived_at", archive.ArchivedAt)
if err := os.Remove(archive.ArchivePath); err != nil {
a.log.Warn("Failed to remove old WAL archive", "file", archive.ArchivePath, "error", err)
continue
}
deleted++
}
}
a.log.Info("WAL cleanup completed", "deleted", deleted, "total_archives", len(archives))
return deleted, nil
}
// GetArchiveStats returns statistics about WAL archives
func (a *Archiver) GetArchiveStats(config ArchiveConfig) (*ArchiveStats, error) {
archives, err := a.ListArchivedWALFiles(config)
if err != nil {
return nil, err
}
stats := &ArchiveStats{
TotalFiles: len(archives),
CompressedFiles: 0,
EncryptedFiles: 0,
TotalSize: 0,
}
if len(archives) > 0 {
stats.OldestArchive = archives[0].ArchivedAt
stats.NewestArchive = archives[0].ArchivedAt
}
for _, archive := range archives {
stats.TotalSize += archive.ArchivedSize
if archive.Compressed {
stats.CompressedFiles++
}
if archive.Encrypted {
stats.EncryptedFiles++
}
if archive.ArchivedAt.Before(stats.OldestArchive) {
stats.OldestArchive = archive.ArchivedAt
}
if archive.ArchivedAt.After(stats.NewestArchive) {
stats.NewestArchive = archive.ArchivedAt
}
}
return stats, nil
}
// ArchiveStats contains statistics about WAL archives
type ArchiveStats struct {
TotalFiles int `json:"total_files"`
CompressedFiles int `json:"compressed_files"`
EncryptedFiles int `json:"encrypted_files"`
TotalSize int64 `json:"total_size"`
OldestArchive time.Time `json:"oldest_archive"`
NewestArchive time.Time `json:"newest_archive"`
}
// FormatSize returns human-readable size
func (s *ArchiveStats) FormatSize() string {
const (
KB = 1024
MB = 1024 * KB
GB = 1024 * MB
)
size := float64(s.TotalSize)
switch {
case size >= GB:
return fmt.Sprintf("%.2f GB", size/GB)
case size >= MB:
return fmt.Sprintf("%.2f MB", size/MB)
case size >= KB:
return fmt.Sprintf("%.2f KB", size/KB)
default:
return fmt.Sprintf("%d B", s.TotalSize)
}
}

386
internal/wal/pitr_config.go Normal file
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@@ -0,0 +1,386 @@
package wal
import (
"bufio"
"context"
"fmt"
"os"
"os/exec"
"path/filepath"
"regexp"
"strings"
"time"
"dbbackup/internal/config"
"dbbackup/internal/logger"
)
// PITRManager manages Point-in-Time Recovery configuration
type PITRManager struct {
cfg *config.Config
log logger.Logger
}
// PITRConfig holds PITR settings
type PITRConfig struct {
Enabled bool
ArchiveMode string // "on", "off", "always"
ArchiveCommand string
ArchiveDir string
WALLevel string // "minimal", "replica", "logical"
MaxWALSenders int
WALKeepSize string // e.g., "1GB"
RestoreCommand string
}
// RecoveryTarget specifies the point-in-time to recover to
type RecoveryTarget struct {
TargetTime *time.Time // Recover to specific timestamp
TargetXID string // Recover to transaction ID
TargetName string // Recover to named restore point
TargetLSN string // Recover to Log Sequence Number
TargetImmediate bool // Recover as soon as consistent state is reached
TargetInclusive bool // Include target transaction
RecoveryEndAction string // "pause", "promote", "shutdown"
}
// NewPITRManager creates a new PITR manager
func NewPITRManager(cfg *config.Config, log logger.Logger) *PITRManager {
return &PITRManager{
cfg: cfg,
log: log,
}
}
// EnablePITR configures PostgreSQL for PITR by modifying postgresql.conf
func (pm *PITRManager) EnablePITR(ctx context.Context, archiveDir string) error {
pm.log.Info("Enabling PITR (Point-in-Time Recovery)", "archive_dir", archiveDir)
// Ensure archive directory exists
if err := os.MkdirAll(archiveDir, 0700); err != nil {
return fmt.Errorf("failed to create WAL archive directory: %w", err)
}
// Find postgresql.conf location
confPath, err := pm.findPostgreSQLConf(ctx)
if err != nil {
return fmt.Errorf("failed to locate postgresql.conf: %w", err)
}
pm.log.Info("Found PostgreSQL configuration", "path", confPath)
// Backup original configuration
backupPath := confPath + ".backup." + time.Now().Format("20060102_150405")
if err := pm.backupFile(confPath, backupPath); err != nil {
return fmt.Errorf("failed to backup postgresql.conf: %w", err)
}
pm.log.Info("Created configuration backup", "backup", backupPath)
// Get absolute path to dbbackup binary
dbbackupPath, err := os.Executable()
if err != nil {
return fmt.Errorf("failed to get dbbackup executable path: %w", err)
}
// Build archive command that calls dbbackup
archiveCommand := fmt.Sprintf("%s wal archive %%p %%f --archive-dir %s", dbbackupPath, archiveDir)
// Settings to enable PITR
settings := map[string]string{
"wal_level": "replica", // Required for PITR
"archive_mode": "on",
"archive_command": archiveCommand,
"max_wal_senders": "3",
"wal_keep_size": "1GB", // Keep at least 1GB of WAL
}
// Update postgresql.conf
if err := pm.updatePostgreSQLConf(confPath, settings); err != nil {
return fmt.Errorf("failed to update postgresql.conf: %w", err)
}
pm.log.Info("✅ PITR configuration updated successfully")
pm.log.Warn("⚠️ PostgreSQL restart required for changes to take effect")
pm.log.Info("To restart PostgreSQL:")
pm.log.Info(" sudo systemctl restart postgresql")
pm.log.Info(" OR: sudo pg_ctlcluster <version> <cluster> restart")
return nil
}
// DisablePITR disables PITR by setting archive_mode = off
func (pm *PITRManager) DisablePITR(ctx context.Context) error {
pm.log.Info("Disabling PITR")
confPath, err := pm.findPostgreSQLConf(ctx)
if err != nil {
return fmt.Errorf("failed to locate postgresql.conf: %w", err)
}
// Backup configuration
backupPath := confPath + ".backup." + time.Now().Format("20060102_150405")
if err := pm.backupFile(confPath, backupPath); err != nil {
return fmt.Errorf("failed to backup postgresql.conf: %w", err)
}
settings := map[string]string{
"archive_mode": "off",
"archive_command": "", // Clear command
}
if err := pm.updatePostgreSQLConf(confPath, settings); err != nil {
return fmt.Errorf("failed to update postgresql.conf: %w", err)
}
pm.log.Info("✅ PITR disabled successfully")
pm.log.Warn("⚠️ PostgreSQL restart required")
return nil
}
// GetCurrentPITRConfig reads current PITR settings from PostgreSQL
func (pm *PITRManager) GetCurrentPITRConfig(ctx context.Context) (*PITRConfig, error) {
confPath, err := pm.findPostgreSQLConf(ctx)
if err != nil {
return nil, err
}
file, err := os.Open(confPath)
if err != nil {
return nil, fmt.Errorf("failed to open postgresql.conf: %w", err)
}
defer file.Close()
config := &PITRConfig{}
scanner := bufio.NewScanner(file)
for scanner.Scan() {
line := strings.TrimSpace(scanner.Text())
// Skip comments and empty lines
if line == "" || strings.HasPrefix(line, "#") {
continue
}
// Parse key = value
parts := strings.SplitN(line, "=", 2)
if len(parts) != 2 {
continue
}
key := strings.TrimSpace(parts[0])
value := strings.Trim(strings.TrimSpace(parts[1]), "'\"")
switch key {
case "wal_level":
config.WALLevel = value
case "archive_mode":
config.ArchiveMode = value
config.Enabled = (value == "on" || value == "always")
case "archive_command":
config.ArchiveCommand = value
case "max_wal_senders":
fmt.Sscanf(value, "%d", &config.MaxWALSenders)
case "wal_keep_size":
config.WALKeepSize = value
case "restore_command":
config.RestoreCommand = value
}
}
if err := scanner.Err(); err != nil {
return nil, fmt.Errorf("error reading postgresql.conf: %w", err)
}
return config, nil
}
// CreateRecoveryConf creates recovery configuration for PITR restore
// PostgreSQL 12+: Creates recovery.signal and modifies postgresql.conf
// PostgreSQL <12: Creates recovery.conf
func (pm *PITRManager) CreateRecoveryConf(ctx context.Context, dataDir string, target RecoveryTarget, walArchiveDir string) error {
pm.log.Info("Creating recovery configuration", "data_dir", dataDir)
// Detect PostgreSQL version to determine recovery file format
version, err := pm.getPostgreSQLVersion(ctx)
if err != nil {
pm.log.Warn("Could not detect PostgreSQL version, assuming >= 12", "error", err)
version = 12 // Default to newer format
}
if version >= 12 {
return pm.createRecoverySignal(ctx, dataDir, target, walArchiveDir)
} else {
return pm.createLegacyRecoveryConf(dataDir, target, walArchiveDir)
}
}
// createRecoverySignal creates recovery.signal for PostgreSQL 12+
func (pm *PITRManager) createRecoverySignal(ctx context.Context, dataDir string, target RecoveryTarget, walArchiveDir string) error {
// Create recovery.signal file (empty file that triggers recovery mode)
signalPath := filepath.Join(dataDir, "recovery.signal")
if err := os.WriteFile(signalPath, []byte{}, 0600); err != nil {
return fmt.Errorf("failed to create recovery.signal: %w", err)
}
pm.log.Info("Created recovery.signal", "path", signalPath)
// Recovery settings go in postgresql.auto.conf (PostgreSQL 12+)
autoConfPath := filepath.Join(dataDir, "postgresql.auto.conf")
// Build recovery settings
var settings []string
settings = append(settings, fmt.Sprintf("restore_command = 'cp %s/%%f %%p'", walArchiveDir))
if target.TargetTime != nil {
settings = append(settings, fmt.Sprintf("recovery_target_time = '%s'", target.TargetTime.Format("2006-01-02 15:04:05")))
} else if target.TargetXID != "" {
settings = append(settings, fmt.Sprintf("recovery_target_xid = '%s'", target.TargetXID))
} else if target.TargetName != "" {
settings = append(settings, fmt.Sprintf("recovery_target_name = '%s'", target.TargetName))
} else if target.TargetLSN != "" {
settings = append(settings, fmt.Sprintf("recovery_target_lsn = '%s'", target.TargetLSN))
} else if target.TargetImmediate {
settings = append(settings, "recovery_target = 'immediate'")
}
if target.RecoveryEndAction != "" {
settings = append(settings, fmt.Sprintf("recovery_target_action = '%s'", target.RecoveryEndAction))
}
// Append to postgresql.auto.conf
f, err := os.OpenFile(autoConfPath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0600)
if err != nil {
return fmt.Errorf("failed to open postgresql.auto.conf: %w", err)
}
defer f.Close()
if _, err := f.WriteString("\n# PITR Recovery Configuration (added by dbbackup)\n"); err != nil {
return err
}
for _, setting := range settings {
if _, err := f.WriteString(setting + "\n"); err != nil {
return err
}
}
pm.log.Info("Recovery configuration added to postgresql.auto.conf", "path", autoConfPath)
return nil
}
// createLegacyRecoveryConf creates recovery.conf for PostgreSQL < 12
func (pm *PITRManager) createLegacyRecoveryConf(dataDir string, target RecoveryTarget, walArchiveDir string) error {
recoveryConfPath := filepath.Join(dataDir, "recovery.conf")
var content strings.Builder
content.WriteString("# Recovery Configuration (created by dbbackup)\n")
content.WriteString(fmt.Sprintf("restore_command = 'cp %s/%%f %%p'\n", walArchiveDir))
if target.TargetTime != nil {
content.WriteString(fmt.Sprintf("recovery_target_time = '%s'\n", target.TargetTime.Format("2006-01-02 15:04:05")))
}
// Add other target types...
if err := os.WriteFile(recoveryConfPath, []byte(content.String()), 0600); err != nil {
return fmt.Errorf("failed to create recovery.conf: %w", err)
}
pm.log.Info("Created recovery.conf", "path", recoveryConfPath)
return nil
}
// Helper functions
func (pm *PITRManager) findPostgreSQLConf(ctx context.Context) (string, error) {
// Try common locations
commonPaths := []string{
"/var/lib/postgresql/data/postgresql.conf",
"/etc/postgresql/*/main/postgresql.conf",
"/usr/local/pgsql/data/postgresql.conf",
}
for _, pattern := range commonPaths {
matches, _ := filepath.Glob(pattern)
for _, path := range matches {
if _, err := os.Stat(path); err == nil {
return path, nil
}
}
}
// Try to get from PostgreSQL directly
cmd := exec.CommandContext(ctx, "psql", "-U", pm.cfg.User, "-t", "-c", "SHOW config_file")
output, err := cmd.Output()
if err == nil {
path := strings.TrimSpace(string(output))
if _, err := os.Stat(path); err == nil {
return path, nil
}
}
return "", fmt.Errorf("could not locate postgresql.conf. Please specify --pg-conf-path")
}
func (pm *PITRManager) backupFile(src, dst string) error {
input, err := os.ReadFile(src)
if err != nil {
return err
}
return os.WriteFile(dst, input, 0644)
}
func (pm *PITRManager) updatePostgreSQLConf(confPath string, settings map[string]string) error {
file, err := os.Open(confPath)
if err != nil {
return err
}
defer file.Close()
var lines []string
existingKeys := make(map[string]bool)
scanner := bufio.NewScanner(file)
// Read existing configuration and track which keys are already present
for scanner.Scan() {
line := scanner.Text()
lines = append(lines, line)
// Check if this line sets one of our keys
for key := range settings {
if matched, _ := regexp.MatchString(fmt.Sprintf(`^\s*%s\s*=`, key), line); matched {
existingKeys[key] = true
}
}
}
if err := scanner.Err(); err != nil {
return err
}
// Append missing settings
for key, value := range settings {
if !existingKeys[key] {
if value == "" {
lines = append(lines, fmt.Sprintf("# %s = '' # Disabled by dbbackup", key))
} else {
lines = append(lines, fmt.Sprintf("%s = '%s' # Added by dbbackup", key, value))
}
}
}
// Write updated configuration
output := strings.Join(lines, "\n") + "\n"
return os.WriteFile(confPath, []byte(output), 0644)
}
func (pm *PITRManager) getPostgreSQLVersion(ctx context.Context) (int, error) {
cmd := exec.CommandContext(ctx, "psql", "-U", pm.cfg.User, "-t", "-c", "SHOW server_version")
output, err := cmd.Output()
if err != nil {
return 0, err
}
versionStr := strings.TrimSpace(string(output))
var major int
fmt.Sscanf(versionStr, "%d", &major)
return major, nil
}