refactor: cache index

internal/cache/index.go

@@ -0,0 +1,452 @@
+package cache
+
+import (
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/0xJacky/Nginx-UI/internal/nginx"
+	"github.com/fsnotify/fsnotify"
+	"github.com/uozi-tech/cosy/logger"
+)
+
+// ScanCallback is a function that gets called during config scanning
+// It receives the config file path and contents
+type ScanCallback func(configPath string, content []byte) error
+
+// Scanner is responsible for scanning and watching nginx config files
+type Scanner struct {
+	watcher       *fsnotify.Watcher      // File system watcher
+	scanTicker    *time.Ticker           // Ticker for periodic scanning
+	initialized   bool                   // Whether the scanner has been initialized
+	scanning      bool                   // Whether a scan is currently in progress
+	scanMutex     sync.RWMutex           // Mutex for protecting the scanning state
+	statusChan    chan bool              // Channel to broadcast scanning status changes
+	subscribers   map[chan bool]struct{} // Set of subscribers
+	subscriberMux sync.RWMutex           // Mutex for protecting the subscribers map
+}
+
+// Global variables
+var (
+	// scanner is the singleton instance of Scanner
+	scanner              *Scanner
+	configScannerInitMux sync.Mutex
+
+	// This regex matches: include directives in nginx config files
+	includeRegex = regexp.MustCompile(`include\s+([^;]+);`)
+
+	// Global callbacks that will be executed during config file scanning
+	scanCallbacks      []ScanCallback
+	scanCallbacksMutex sync.RWMutex
+)
+
+func init() {
+	// Initialize the callbacks slice
+	scanCallbacks = make([]ScanCallback, 0)
+}
+
+// InitScanner initializes the config scanner
+func InitScanner() {
+	s := GetScanner()
+	err := s.Initialize()
+	if err != nil {
+		logger.Error("Failed to initialize config scanner:", err)
+	}
+}
+
+// GetScanner returns the singleton instance of Scanner
+func GetScanner() *Scanner {
+	configScannerInitMux.Lock()
+	defer configScannerInitMux.Unlock()
+
+	if scanner == nil {
+		scanner = &Scanner{
+			statusChan:  make(chan bool, 10), // Buffer to prevent blocking
+			subscribers: make(map[chan bool]struct{}),
+		}
+
+		// Start broadcaster goroutine
+		go scanner.broadcastStatus()
+	}
+	return scanner
+}
+
+// RegisterCallback adds a callback function to be executed during scans
+// This function can be called before Scanner is initialized
+func RegisterCallback(callback ScanCallback) {
+	scanCallbacksMutex.Lock()
+	defer scanCallbacksMutex.Unlock()
+	scanCallbacks = append(scanCallbacks, callback)
+}
+
+// broadcastStatus listens for status changes and broadcasts to all subscribers
+func (s *Scanner) broadcastStatus() {
+	for status := range s.statusChan {
+		s.subscriberMux.RLock()
+		for ch := range s.subscribers {
+			// Non-blocking send to prevent slow subscribers from blocking others
+			select {
+			case ch <- status:
+			default:
+				// Skip if channel buffer is full
+			}
+		}
+		s.subscriberMux.RUnlock()
+	}
+}
+
+// SubscribeScanningStatus allows a client to subscribe to scanning status changes
+func SubscribeScanningStatus() chan bool {
+	s := GetScanner()
+	ch := make(chan bool, 5) // Buffer to prevent blocking
+
+	// Add to subscribers
+	s.subscriberMux.Lock()
+	s.subscribers[ch] = struct{}{}
+	s.subscriberMux.Unlock()
+
+	// Send current status immediately
+	s.scanMutex.RLock()
+	currentStatus := s.scanning
+	s.scanMutex.RUnlock()
+
+	// Non-blocking send
+	select {
+	case ch <- currentStatus:
+	default:
+	}
+
+	return ch
+}
+
+// UnsubscribeScanningStatus removes a subscriber from receiving status updates
+func UnsubscribeScanningStatus(ch chan bool) {
+	s := GetScanner()
+
+	s.subscriberMux.Lock()
+	delete(s.subscribers, ch)
+	s.subscriberMux.Unlock()
+
+	// Close the channel so the client knows it's unsubscribed
+	close(ch)
+}
+
+// Initialize sets up the scanner and starts watching for file changes
+func (s *Scanner) Initialize() error {
+	if s.initialized {
+		return nil
+	}
+
+	// Create a new watcher
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		return err
+	}
+	s.watcher = watcher
+
+	// Scan for the first time
+	err = s.ScanAllConfigs()
+	if err != nil {
+		return err
+	}
+
+	// Setup watcher for config directory
+	configDir := filepath.Dir(nginx.GetConfPath("", ""))
+	availableDir := nginx.GetConfPath("sites-available", "")
+	enabledDir := nginx.GetConfPath("sites-enabled", "")
+	streamAvailableDir := nginx.GetConfPath("stream-available", "")
+	streamEnabledDir := nginx.GetConfPath("stream-enabled", "")
+
+	// Watch the main directories
+	err = s.watcher.Add(configDir)
+	if err != nil {
+		logger.Error("Failed to watch config directory:", err)
+	}
+
+	// Watch sites-available and sites-enabled if they exist
+	if _, err := os.Stat(availableDir); err == nil {
+		err = s.watcher.Add(availableDir)
+		if err != nil {
+			logger.Error("Failed to watch sites-available directory:", err)
+		}
+	}
+
+	if _, err := os.Stat(enabledDir); err == nil {
+		err = s.watcher.Add(enabledDir)
+		if err != nil {
+			logger.Error("Failed to watch sites-enabled directory:", err)
+		}
+	}
+
+	// Watch stream-available and stream-enabled if they exist
+	if _, err := os.Stat(streamAvailableDir); err == nil {
+		err = s.watcher.Add(streamAvailableDir)
+		if err != nil {
+			logger.Error("Failed to watch stream-available directory:", err)
+		}
+	}
+
+	if _, err := os.Stat(streamEnabledDir); err == nil {
+		err = s.watcher.Add(streamEnabledDir)
+		if err != nil {
+			logger.Error("Failed to watch stream-enabled directory:", err)
+		}
+	}
+
+	// Start the watcher goroutine
+	go s.watchForChanges()
+
+	// Setup a ticker for periodic scanning (every 5 minutes)
+	s.scanTicker = time.NewTicker(5 * time.Minute)
+	go func() {
+		for range s.scanTicker.C {
+			err := s.ScanAllConfigs()
+			if err != nil {
+				logger.Error("Periodic config scan failed:", err)
+			}
+		}
+	}()
+
+	s.initialized = true
+	return nil
+}
+
+// watchForChanges handles the fsnotify events and triggers rescans when necessary
+func (s *Scanner) watchForChanges() {
+	for {
+		select {
+		case event, ok := <-s.watcher.Events:
+			if !ok {
+				return
+			}
+
+			// Check if this is a relevant event (create, write, rename, remove)
+			if event.Has(fsnotify.Create) || event.Has(fsnotify.Write) ||
+				event.Has(fsnotify.Rename) || event.Has(fsnotify.Remove) {
+				// If it's a directory, add it to the watch list
+				if event.Has(fsnotify.Create) {
+					fi, err := os.Stat(event.Name)
+					if err == nil && fi.IsDir() {
+						_ = s.watcher.Add(event.Name)
+					}
+				}
+
+				// Process file changes
+				if !event.Has(fsnotify.Remove) {
+					logger.Debug("Config file changed:", event.Name)
+					// Give the system a moment to finish writing the file
+					time.Sleep(100 * time.Millisecond)
+					// Only scan the changed file instead of all configs
+					err := s.scanSingleFile(event.Name)
+					if err != nil {
+						logger.Error("Failed to scan changed file:", err)
+					}
+				} else {
+					// For removed files, we need a full rescan
+					err := s.ScanAllConfigs()
+					if err != nil {
+						logger.Error("Failed to rescan configs after file removal:", err)
+					}
+				}
+			}
+		case err, ok := <-s.watcher.Errors:
+			if !ok {
+				return
+			}
+			logger.Error("Watcher error:", err)
+		}
+	}
+}
+
+// scanSingleFile scans a single file and executes all registered callbacks
+func (s *Scanner) scanSingleFile(filePath string) error {
+	// Set scanning state to true
+	s.scanMutex.Lock()
+	wasScanning := s.scanning
+	s.scanning = true
+	if !wasScanning {
+		// Only broadcast if status changed from not scanning to scanning
+		s.statusChan <- true
+	}
+	s.scanMutex.Unlock()
+
+	// Ensure we reset scanning state when done
+	defer func() {
+		s.scanMutex.Lock()
+		s.scanning = false
+		// Broadcast the completion
+		s.statusChan <- false
+		s.scanMutex.Unlock()
+	}()
+
+	// Open the file
+	file, err := os.Open(filePath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	// Read the entire file content
+	content, err := os.ReadFile(filePath)
+	if err != nil {
+		return err
+	}
+
+	// Execute all registered callbacks
+	scanCallbacksMutex.RLock()
+	for _, callback := range scanCallbacks {
+		err := callback(filePath, content)
+		if err != nil {
+			logger.Error("Callback error for file", filePath, ":", err)
+		}
+	}
+	scanCallbacksMutex.RUnlock()
+
+	// Look for include directives to process included files
+	includeMatches := includeRegex.FindAllSubmatch(content, -1)
+
+	for _, match := range includeMatches {
+		if len(match) >= 2 {
+			includePath := string(match[1])
+			// Handle glob patterns in include directives
+			if strings.Contains(includePath, "*") {
+				// If it's a relative path, make it absolute based on nginx config dir
+				if !filepath.IsAbs(includePath) {
+					configDir := filepath.Dir(nginx.GetConfPath("", ""))
+					includePath = filepath.Join(configDir, includePath)
+				}
+
+				// Expand the glob pattern
+				matchedFiles, err := filepath.Glob(includePath)
+				if err != nil {
+					logger.Error("Error expanding glob pattern:", includePath, err)
+					continue
+				}
+
+				// Process each matched file
+				for _, matchedFile := range matchedFiles {
+					fileInfo, err := os.Stat(matchedFile)
+					if err == nil && !fileInfo.IsDir() {
+						err = s.scanSingleFile(matchedFile)
+						if err != nil {
+							logger.Error("Failed to scan included file:", matchedFile, err)
+						}
+					}
+				}
+			} else {
+				// Handle single file include
+				// If it's a relative path, make it absolute based on nginx config dir
+				if !filepath.IsAbs(includePath) {
+					configDir := filepath.Dir(nginx.GetConfPath("", ""))
+					includePath = filepath.Join(configDir, includePath)
+				}
+
+				fileInfo, err := os.Stat(includePath)
+				if err == nil && !fileInfo.IsDir() {
+					err = s.scanSingleFile(includePath)
+					if err != nil {
+						logger.Error("Failed to scan included file:", includePath, err)
+					}
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+// ScanAllConfigs scans all nginx config files and executes all registered callbacks
+func (s *Scanner) ScanAllConfigs() error {
+	// Set scanning state to true
+	s.scanMutex.Lock()
+	wasScanning := s.scanning
+	s.scanning = true
+	if !wasScanning {
+		// Only broadcast if status changed from not scanning to scanning
+		s.statusChan <- true
+	}
+	s.scanMutex.Unlock()
+
+	// Ensure we reset scanning state when done
+	defer func() {
+		s.scanMutex.Lock()
+		s.scanning = false
+		// Broadcast the completion
+		s.statusChan <- false
+		s.scanMutex.Unlock()
+	}()
+
+	// Get the main config file
+	mainConfigPath := nginx.GetConfPath("", "nginx.conf")
+	err := s.scanSingleFile(mainConfigPath)
+	if err != nil {
+		logger.Error("Failed to scan main config:", err)
+	}
+
+	// Scan sites-available directory
+	sitesAvailablePath := nginx.GetConfPath("sites-available", "")
+	sitesAvailableFiles, err := os.ReadDir(sitesAvailablePath)
+	if err == nil {
+		for _, file := range sitesAvailableFiles {
+			if !file.IsDir() {
+				configPath := filepath.Join(sitesAvailablePath, file.Name())
+				err := s.scanSingleFile(configPath)
+				if err != nil {
+					logger.Error("Failed to scan config:", configPath, err)
+				}
+			}
+		}
+	}
+
+	// Scan stream-available directory if it exists
+	streamAvailablePath := nginx.GetConfPath("stream-available", "")
+	streamAvailableFiles, err := os.ReadDir(streamAvailablePath)
+	if err == nil {
+		for _, file := range streamAvailableFiles {
+			if !file.IsDir() {
+				configPath := filepath.Join(streamAvailablePath, file.Name())
+				err := s.scanSingleFile(configPath)
+				if err != nil {
+					logger.Error("Failed to scan stream config:", configPath, err)
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+// Shutdown cleans up resources used by the scanner
+func (s *Scanner) Shutdown() {
+	if s.watcher != nil {
+		s.watcher.Close()
+	}
+
+	if s.scanTicker != nil {
+		s.scanTicker.Stop()
+	}
+
+	// Clean up subscriber resources
+	s.subscriberMux.Lock()
+	// Close all subscriber channels
+	for ch := range s.subscribers {
+		close(ch)
+	}
+	// Clear the map
+	s.subscribers = make(map[chan bool]struct{})
+	s.subscriberMux.Unlock()
+
+	// Close the status channel
+	close(s.statusChan)
+}
+
+// IsScanningInProgress returns whether a scan is currently in progress
+func IsScanningInProgress() bool {
+	s := GetScanner()
+	s.scanMutex.RLock()
+	defer s.scanMutex.RUnlock()
+	return s.scanning
+}