jenkins-cron/v3.1/clean.go
2025-05-27 11:48:18 +08:00

276 lines
7.6 KiB
Go

package main
import (
"context"
"fmt"
"log"
"os"
"path/filepath"
"runtime"
"sync"
"sync/atomic"
"time"
)
// RemoveStats tracks statistics about the file removal process
type RemoveStats struct {
Total int64 // Total number of files/directories processed
Success int64 // Number of successfully removed files/directories
Failed int64 // Number of files/directories that failed to be removed
Errors []error // Collection of errors encountered during removal
mu sync.Mutex // Mutex to protect concurrent access to Errors slice
}
// RemoveOptions configures the file removal process
type RemoveOptions struct {
Workers int // Number of concurrent workers (defaults to CPU count)
Logger func(format string, args ...any) // Logger function
Retries int // Number of retries for failed removals
Stats *RemoveStats // Statistics collector (optional)
Progress func(current int64) // Progress callback function (optional)
}
// removeResult represents the result of a single file/directory removal operation
type removeResult struct {
Path string // Path that was processed
Err error // Error if removal failed, nil if successful
}
// Remove recursively removes a directory and all its contents with concurrency support
func Remove(ctx context.Context, path string, opts RemoveOptions) error {
// Apply default options if not specified
if opts.Workers <= 0 {
opts.Workers = runtime.NumCPU()
}
if opts.Logger == nil {
opts.Logger = log.Printf
}
if opts.Retries < 0 {
opts.Retries = 0
}
if opts.Stats == nil {
opts.Stats = &RemoveStats{}
}
// Validate path
if path == "" {
return fmt.Errorf("empty path provided")
}
// Safety check: prevent removal of critical directories
absPath, err := filepath.Abs(path)
if err == nil {
// List of critical paths that should never be removed
criticalPaths := []string{
"/", "/bin", "/boot", "/dev", "/etc", "/home", "/lib", "/lib64",
"/media", "/mnt", "/opt", "/proc", "/root", "/run", "/sbin",
"/srv", "/sys", "/tmp", "/usr", "/var",
"C:\\", "C:\\Windows", "C:\\Program Files", "C:\\Program Files (x86)",
"C:\\Users",
}
for _, critical := range criticalPaths {
if absPath == critical {
return fmt.Errorf("refusing to remove critical system directory: %s", absPath)
}
}
}
// Check if path exists
info, err := os.Stat(path)
if os.IsNotExist(err) {
opts.Logger("[CLEAN] Path does not exist, skipping: %s", path)
return nil
}
if err != nil {
return fmt.Errorf("failed to access path %s: %w", path, err)
}
// Check if it's a directory
if !info.IsDir() {
opts.Logger("[CLEAN] Path is not a directory, removing file: %s", path)
if err := os.Remove(path); err != nil {
return fmt.Errorf("failed to remove file %s: %w", path, err)
}
if opts.Stats != nil {
atomic.AddInt64(&opts.Stats.Total, 1)
atomic.AddInt64(&opts.Stats.Success, 1)
}
return nil
}
opts.Logger("[CLEAN] Starting removal of directory: %s with %d workers", path, opts.Workers)
// Create channels for work distribution and result collection
workChan := make(chan string, opts.Workers*2)
resultChan := make(chan removeResult, opts.Workers*2)
// Start worker goroutines
var wg sync.WaitGroup
for i := 0; i < opts.Workers; i++ {
wg.Add(1)
go removeWorker(ctx, &wg, workChan, resultChan, opts)
}
// Start directory traversal
go func() {
defer close(workChan)
if err := walkDir(ctx, path, workChan, opts); err != nil {
opts.Logger("[CLEAN] Error walking directory %s: %v", path, err)
}
}()
// Wait for workers to finish and close result channel
go func() {
wg.Wait()
close(resultChan)
}()
// Process results
var firstErr error
for res := range resultChan {
atomic.AddInt64(&opts.Stats.Total, 1)
if res.Err != nil {
atomic.AddInt64(&opts.Stats.Failed, 1)
opts.Stats.mu.Lock()
opts.Stats.Errors = append(opts.Stats.Errors, res.Err)
opts.Stats.mu.Unlock()
if firstErr == nil {
firstErr = res.Err
}
} else {
atomic.AddInt64(&opts.Stats.Success, 1)
}
if opts.Progress != nil {
opts.Progress(atomic.LoadInt64(&opts.Stats.Total))
}
}
// Try to remove the root directory itself
if err := tryRemoveRoot(ctx, path, opts); err != nil && firstErr == nil {
firstErr = err
atomic.AddInt64(&opts.Stats.Failed, 1)
opts.Stats.mu.Lock()
opts.Stats.Errors = append(opts.Stats.Errors, err)
opts.Stats.mu.Unlock()
}
opts.Logger("[CLEAN] Completed removal of %s: Total=%d Success=%d Failed=%d",
path, opts.Stats.Total, opts.Stats.Success, opts.Stats.Failed)
return firstErr
}
// walkDir traverses the directory tree and sends paths to the work channel
// Uses depth-first, reverse order to ensure children are processed before parents
func walkDir(ctx context.Context, root string, workChan chan<- string, opts RemoveOptions) error {
var paths []string
// Walk the directory tree and collect all paths
err := filepath.WalkDir(root, func(subPath string, d os.DirEntry, err error) error {
// Check for context cancellation
if ctx.Err() != nil {
return ctx.Err()
}
// Handle walk errors
if err != nil {
opts.Logger("[CLEAN] Walk error on %s: %v", subPath, err)
return nil // Skip errors and continue
}
// Skip the root directory itself
if subPath != root {
paths = append(paths, subPath)
}
return nil
})
// Process paths in reverse order (depth-first)
for i := len(paths) - 1; i >= 0; i-- {
select {
case <-ctx.Done():
return ctx.Err()
case workChan <- paths[i]:
// Path sent to worker
}
}
return err
}
// removeWorker processes paths from the work channel and removes them
func removeWorker(ctx context.Context, wg *sync.WaitGroup, workChan <-chan string, resultChan chan<- removeResult, opts RemoveOptions) {
defer wg.Done()
for {
select {
case <-ctx.Done():
return
case subPath, ok := <-workChan:
if !ok {
return // Channel closed, exit worker
}
// Try to remove with retries
var err error
for i := 0; i <= opts.Retries; i++ {
// Check if context is cancelled before each attempt
if ctx.Err() != nil {
resultChan <- removeResult{Path: subPath, Err: ctx.Err()}
return
}
err = os.RemoveAll(subPath)
if err == nil {
break // Successful removal
}
// If not the last retry, wait before trying again
if i < opts.Retries {
// Exponential backoff: 100ms, 200ms, 400ms, ...
backoff := time.Duration(100*(1<<i)) * time.Millisecond
select {
case <-ctx.Done():
resultChan <- removeResult{Path: subPath, Err: ctx.Err()}
return
case <-time.After(backoff):
// Continue with retry
}
}
}
// Send result
if err != nil {
opts.Logger("[CLEAN] Failed to remove %s: %v", subPath, err)
resultChan <- removeResult{Path: subPath, Err: fmt.Errorf("remove %q: %w", subPath, err)}
} else {
if opts.Logger != nil {
opts.Logger("[CLEAN] Removed: %s", subPath)
}
resultChan <- removeResult{Path: subPath, Err: nil}
}
}
}
}
// tryRemoveRoot attempts to remove the root directory itself
func tryRemoveRoot(ctx context.Context, path string, opts RemoveOptions) error {
// Check for context cancellation
select {
case <-ctx.Done():
return ctx.Err()
default:
// Continue
}
// Try to remove the directory
if err := os.Remove(path); err != nil {
// It's common for this to fail if the directory wasn't empty
opts.Logger("[CLEAN] Note: Could not remove root directory %s: %v", path, err)
return fmt.Errorf("remove root directory %q: %w", path, err)
}
opts.Logger("[CLEAN] Successfully removed root directory: %s", path)
return nil
}