Bump version to 4.2.8

- Comprehensive WAL archive stats in 'pitr status' command
- Shows: file count, size, compression rate, oldest/newest, time span
- Auto-detects archive dir from PostgreSQL archive_command
- Supports compressed/encrypted WAL files
- Memory: ~90% reduction in TUI operations (from v4.2.7)

CHANGELOG.md

@@ -5,6 +5,41 @@ All notable changes to dbbackup will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [4.2.8] - 2026-01-30
+
+### Added - MEDIUM Priority Features
+
+- **#10: WAL Archive Statistics (MEDIUM priority)**
+  - `dbbackup pitr status` now shows comprehensive WAL archive statistics
+  - Displays: total files, total size, compression rate, oldest/newest WAL, time span
+  - Auto-detects archive directory from PostgreSQL `archive_command`
+  - Supports compressed (.gz, .zst, .lz4) and encrypted (.enc) WAL files
+  - **Problem**: No visibility into WAL archive health and growth
+  - **Solution**: Real-time stats in PITR status command, helps identify retention issues
+
+**Example Output:**
+```
+WAL Archive Statistics:
+======================================================
+  Total Files:      1,234
+  Total Size:       19.8 GB
+  Average Size:     16.4 MB
+  Compressed:       1,234 files (68.5% saved)
+  Encrypted:        1,234 files
+
+  Oldest WAL:       000000010000000000000042
+    Created:        2026-01-15 08:30:00
+  Newest WAL:       000000010000000000004D2F
+    Created:        2026-01-30 17:45:30
+  Time Span:        15.4 days
+```
+
+**Files Modified:**
+- `internal/wal/archiver.go`: Extended `ArchiveStats` struct with detailed fields
+- `internal/wal/archiver.go`: Added `GetArchiveStats()`, `FormatArchiveStats()` functions
+- `cmd/pitr.go`: Integrated stats into `pitr status` command
+- `cmd/pitr.go`: Added `extractArchiveDirFromCommand()` helper
+
 ## [4.2.7] - 2026-01-30
 
 ### Added - HIGH Priority Features

cmd/pitr.go

@@ -5,6 +5,7 @@ import (
 	"database/sql"
 	"fmt"
 	"os"
+	"strings"
 	"time"
 
 	"github.com/spf13/cobra"
@@ -505,12 +506,24 @@ func runPITRStatus(cmd *cobra.Command, args []string) error {
 
 	// 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)")
+		archiveDir := extractArchiveDirFromCommand(config.ArchiveCommand)
+		if archiveDir != "" {
+			fmt.Println()
+			fmt.Println("WAL Archive Statistics:")
+			fmt.Println("======================================================")
+			stats, err := wal.GetArchiveStats(archiveDir)
+			if err != nil {
+				fmt.Printf("  ⚠ Could not read archive: %v\n", err)
+				fmt.Printf("  (Archive directory: %s)\n", archiveDir)
+			} else {
+				fmt.Print(wal.FormatArchiveStats(stats))
+			}
+		} else {
+			fmt.Println()
+			fmt.Println("WAL Archive Statistics:")
+			fmt.Println("======================================================")
+			fmt.Println("  (Use 'dbbackup wal list --archive-dir <dir>' to view archives)")
+		}
 	}
 
 	return nil
@@ -1309,3 +1322,36 @@ func runMySQLPITREnable(cmd *cobra.Command, args []string) error {
 
 	return nil
 }
+
+// extractArchiveDirFromCommand attempts to extract the archive directory
+// from a PostgreSQL archive_command string
+// Example: "dbbackup wal archive %p %f --archive-dir=/mnt/wal" → "/mnt/wal"
+func extractArchiveDirFromCommand(command string) string {
+	// Look for common patterns:
+	// 1. --archive-dir=/path
+	// 2. --archive-dir /path
+	// 3. Plain path argument
+
+	parts := strings.Fields(command)
+	for i, part := range parts {
+		// Pattern: --archive-dir=/path
+		if strings.HasPrefix(part, "--archive-dir=") {
+			return strings.TrimPrefix(part, "--archive-dir=")
+		}
+		// Pattern: --archive-dir /path
+		if part == "--archive-dir" && i+1 < len(parts) {
+			return parts[i+1]
+		}
+	}
+
+	// If command contains dbbackup, the last argument might be the archive dir
+	if strings.Contains(command, "dbbackup") && len(parts) > 2 {
+		lastArg := parts[len(parts)-1]
+		// Check if it looks like a path
+		if strings.HasPrefix(lastArg, "/") || strings.HasPrefix(lastArg, "./") {
+			return lastArg
+		}
+	}
+
+	return ""
+}

internal/wal/archiver.go

@@ -367,6 +367,11 @@ type ArchiveStats struct {
 	TotalSize       int64     `json:"total_size"`
 	OldestArchive   time.Time `json:"oldest_archive"`
 	NewestArchive   time.Time `json:"newest_archive"`
+	OldestWAL       string    `json:"oldest_wal,omitempty"`
+	NewestWAL       string    `json:"newest_wal,omitempty"`
+	TimeSpan        string    `json:"time_span,omitempty"`
+	AvgFileSize     int64     `json:"avg_file_size,omitempty"`
+	CompressionRate float64   `json:"compression_rate,omitempty"`
 }
 
 // FormatSize returns human-readable size
@@ -389,3 +394,199 @@ func (s *ArchiveStats) FormatSize() string {
 		return fmt.Sprintf("%d B", s.TotalSize)
 	}
 }
+
+// GetArchiveStats scans a WAL archive directory and returns comprehensive statistics
+func GetArchiveStats(archiveDir string) (*ArchiveStats, error) {
+	stats := &ArchiveStats{
+		OldestArchive: time.Now(),
+		NewestArchive: time.Time{},
+	}
+
+	// Check if directory exists
+	if _, err := os.Stat(archiveDir); os.IsNotExist(err) {
+		return nil, fmt.Errorf("archive directory does not exist: %s", archiveDir)
+	}
+
+	type walFileInfo struct {
+		name    string
+		size    int64
+		modTime time.Time
+	}
+
+	var walFiles []walFileInfo
+	var compressedSize int64
+	var originalSize int64
+
+	// Walk the archive directory
+	err := filepath.Walk(archiveDir, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return nil // Skip files we can't read
+		}
+
+		// Skip directories
+		if info.IsDir() {
+			return nil
+		}
+
+		// Check if this is a WAL file (including compressed/encrypted variants)
+		name := info.Name()
+		if !isWALFileName(name) {
+			return nil
+		}
+
+		stats.TotalFiles++
+		stats.TotalSize += info.Size()
+
+		// Track compressed/encrypted files
+		if strings.HasSuffix(name, ".gz") || strings.HasSuffix(name, ".zst") || strings.HasSuffix(name, ".lz4") {
+			stats.CompressedFiles++
+			compressedSize += info.Size()
+			// Estimate original size (WAL files are typically 16MB)
+			originalSize += 16 * 1024 * 1024
+		}
+		if strings.HasSuffix(name, ".enc") || strings.Contains(name, ".encrypted") {
+			stats.EncryptedFiles++
+		}
+
+		// Track oldest/newest
+		if info.ModTime().Before(stats.OldestArchive) {
+			stats.OldestArchive = info.ModTime()
+			stats.OldestWAL = name
+		}
+		if info.ModTime().After(stats.NewestArchive) {
+			stats.NewestArchive = info.ModTime()
+			stats.NewestWAL = name
+		}
+
+		// Store file info for additional calculations
+		walFiles = append(walFiles, walFileInfo{
+			name:    name,
+			size:    info.Size(),
+			modTime: info.ModTime(),
+		})
+
+		return nil
+	})
+
+	if err != nil {
+		return nil, fmt.Errorf("failed to scan archive directory: %w", err)
+	}
+
+	// Return early if no WAL files found
+	if stats.TotalFiles == 0 {
+		return stats, nil
+	}
+
+	// Calculate average file size
+	stats.AvgFileSize = stats.TotalSize / int64(stats.TotalFiles)
+
+	// Calculate compression rate if we have compressed files
+	if stats.CompressedFiles > 0 && originalSize > 0 {
+		stats.CompressionRate = (1.0 - float64(compressedSize)/float64(originalSize)) * 100.0
+	}
+
+	// Calculate time span
+	duration := stats.NewestArchive.Sub(stats.OldestArchive)
+	stats.TimeSpan = formatDuration(duration)
+
+	return stats, nil
+}
+
+// isWALFileName checks if a filename looks like a PostgreSQL WAL file
+func isWALFileName(name string) bool {
+	// Strip compression/encryption extensions
+	baseName := name
+	baseName = strings.TrimSuffix(baseName, ".gz")
+	baseName = strings.TrimSuffix(baseName, ".zst")
+	baseName = strings.TrimSuffix(baseName, ".lz4")
+	baseName = strings.TrimSuffix(baseName, ".enc")
+	baseName = strings.TrimSuffix(baseName, ".encrypted")
+
+	// PostgreSQL WAL files are 24 hex characters (e.g., 000000010000000000000001)
+	// Also accept .backup and .history files
+	if len(baseName) == 24 {
+		// Check if all hex
+		for _, c := range baseName {
+			if !((c >= '0' && c <= '9') || (c >= 'A' && c <= 'F') || (c >= 'a' && c <= 'f')) {
+				return false
+			}
+		}
+		return true
+	}
+
+	// Accept .backup and .history files
+	if strings.HasSuffix(baseName, ".backup") || strings.HasSuffix(baseName, ".history") {
+		return true
+	}
+
+	return false
+}
+
+// formatDuration formats a duration into a human-readable string
+func formatDuration(d time.Duration) string {
+	if d < time.Hour {
+		return fmt.Sprintf("%.0f minutes", d.Minutes())
+	}
+	if d < 24*time.Hour {
+		return fmt.Sprintf("%.1f hours", d.Hours())
+	}
+	days := d.Hours() / 24
+	if days < 30 {
+		return fmt.Sprintf("%.1f days", days)
+	}
+	if days < 365 {
+		return fmt.Sprintf("%.1f months", days/30)
+	}
+	return fmt.Sprintf("%.1f years", days/365)
+}
+
+// FormatArchiveStats formats archive statistics for display
+func FormatArchiveStats(stats *ArchiveStats) string {
+	if stats.TotalFiles == 0 {
+		return "  No WAL files found in archive"
+	}
+
+	var sb strings.Builder
+
+	sb.WriteString(fmt.Sprintf("  Total Files:      %d\n", stats.TotalFiles))
+	sb.WriteString(fmt.Sprintf("  Total Size:       %s\n", stats.FormatSize()))
+
+	if stats.AvgFileSize > 0 {
+		const (
+			KB = 1024
+			MB = 1024 * KB
+		)
+		avgSize := float64(stats.AvgFileSize)
+		if avgSize >= MB {
+			sb.WriteString(fmt.Sprintf("  Average Size:     %.2f MB\n", avgSize/MB))
+		} else {
+			sb.WriteString(fmt.Sprintf("  Average Size:     %.2f KB\n", avgSize/KB))
+		}
+	}
+
+	if stats.CompressedFiles > 0 {
+		sb.WriteString(fmt.Sprintf("  Compressed:       %d files", stats.CompressedFiles))
+		if stats.CompressionRate > 0 {
+			sb.WriteString(fmt.Sprintf(" (%.1f%% saved)", stats.CompressionRate))
+		}
+		sb.WriteString("\n")
+	}
+
+	if stats.EncryptedFiles > 0 {
+		sb.WriteString(fmt.Sprintf("  Encrypted:        %d files\n", stats.EncryptedFiles))
+	}
+
+	if stats.OldestWAL != "" {
+		sb.WriteString(fmt.Sprintf("\n  Oldest WAL:       %s\n", stats.OldestWAL))
+		sb.WriteString(fmt.Sprintf("    Created:        %s\n", stats.OldestArchive.Format("2006-01-02 15:04:05")))
+	}
+	if stats.NewestWAL != "" {
+		sb.WriteString(fmt.Sprintf("  Newest WAL:       %s\n", stats.NewestWAL))
+		sb.WriteString(fmt.Sprintf("    Created:        %s\n", stats.NewestArchive.Format("2006-01-02 15:04:05")))
+	}
+	if stats.TimeSpan != "" {
+		sb.WriteString(fmt.Sprintf("  Time Span:        %s\n", stats.TimeSpan))
+	}
+
+	return sb.String()
+}

main.go

@@ -16,7 +16,7 @@ import (
 
 // Build information (set by ldflags)
 var (
-	version   = "4.2.7"
+	version   = "4.2.8"
 	buildTime = "unknown"
 	gitCommit = "unknown"
 )