reuse filewatcher

internal/filewatcher/filewatcher.go

@@ -8,6 +8,7 @@ package filewatcher
 import (
 	"errors"
 	"fmt"
+	"os"
 	"path/filepath"
 	"sync"
 
@@ -90,7 +91,6 @@ func (fw *fileWatcher) Add(path string) error {
 	return err
 }
 
-// Stop watching a path
 func (fw *fileWatcher) Remove(path string) error {
 	fw.mu.Lock()
 	defer fw.mu.Unlock()
@@ -142,9 +142,7 @@ func (fw *fileWatcher) getWorker(path string) (*workerState, string, string, err
 		return nil, "", "", errors.New("using a closed watcher")
 	}
 
-	cleanedPath := filepath.Clean(path)
-	parentPath, _ := filepath.Split(cleanedPath)
-
+	cleanedPath, parentPath := getPath(path)
 	ws, workerExists := fw.workers[parentPath]
 	if !workerExists {
 		wk, err := newWorker(parentPath, fw.funcs)
@@ -167,8 +165,7 @@ func (fw *fileWatcher) findWorker(path string) (*workerState, string, error) {
 		return nil, "", errors.New("using a closed watcher")
 	}
 
-	cleanedPath := filepath.Clean(path)
-	parentPath, _ := filepath.Split(cleanedPath)
+	cleanedPath, parentPath := getPath(path)
 
 	ws, workerExists := fw.workers[parentPath]
 	if !workerExists {
@@ -177,3 +174,13 @@ func (fw *fileWatcher) findWorker(path string) (*workerState, string, error) {
 
 	return ws, cleanedPath, nil
 }
+
+func getPath(path string) (cleanedPath, parentPath string) {
+	cleanedPath = filepath.Clean(path)
+	parentPath, _ = filepath.Split(cleanedPath)
+	if f, err := os.Lstat(cleanedPath); err == nil && f.IsDir() {
+		parentPath = cleanedPath
+	}
+
+	return
+}

internal/filewatcher/filewatcher_test.go

@@ -14,6 +14,7 @@ import (
 	"runtime"
 	"sync"
 	"testing"
+	"time"
 
 	"github.com/fsnotify/fsnotify"
 	"github.com/stretchr/testify/require"
@@ -173,6 +174,44 @@ func TestWatchFile(t *testing.T) {
 	})
 }
 
+func TestWatchDir(t *testing.T) {
+	// Given a file being watched
+	watchFile := newWatchFile(t)
+	_, err := os.Stat(watchFile)
+	require.NoError(t, err)
+
+	w := NewWatcher()
+	defer func() {
+		_ = w.Close()
+	}()
+	d := path.Dir(watchFile)
+	require.NoError(t, w.Add(d))
+
+	timeout := time.After(5 * time.Second)
+
+	wg := sync.WaitGroup{}
+	var timeoutErr error
+	wg.Add(1)
+	go func() {
+		select {
+		case <-w.Events(d):
+
+		case <-w.Events(watchFile):
+
+		case <-timeout:
+			timeoutErr = errors.New("timeout")
+		}
+		wg.Done()
+	}()
+
+	// Overwriting the file and waiting its event to be received.
+	err = os.WriteFile(watchFile, []byte("foo: baz\n"), 0o600)
+	require.NoError(t, err)
+	wg.Wait()
+
+	require.NoErrorf(t, timeoutErr, "timeout waiting for event")
+}
+
 func TestWatcherLifecycle(t *testing.T) {
 	watchFile1, watchFile2 := newTwoWatchFile(t)
 
@@ -295,27 +334,23 @@ func TestBadAddWatcher(t *testing.T) {
 
 func TestDuplicateAdd(t *testing.T) {
 	w := NewWatcher()
-
 	name := newWatchFile(t)
+	defer func() {
+		_ = w.Close()
+		_ = os.Remove(name)
+	}()
 
-	if err := w.Add(name); err != nil {
-		t.Errorf("Expecting nil, got %v", err)
-	}
-
-	if err := w.Add(name); err == nil {
-		t.Errorf("Expecting error, got nil")
-	}
-
-	_ = w.Close()
+	require.NoError(t, w.Add(name))
+	require.Error(t, w.Add(name))
 }
 
 func TestBogusRemove(t *testing.T) {
 	w := NewWatcher()
-
 	name := newWatchFile(t)
-	if err := w.Remove(name); err == nil {
-		t.Errorf("Expecting error, got nil")
-	}
+	defer func() {
+		_ = w.Close()
+		_ = os.Remove(name)
+	}()
 
-	_ = w.Close()
+	require.Error(t, w.Remove(name))
 }

internal/filewatcher/worker.go

@@ -20,7 +20,7 @@
 type worker struct {
 	mu sync.RWMutex
 
-	// watcher is an fsnotify watcher that watches the parent
+	// watcher is a fsnotify watcher that watches the parent
 	// dir of watchedFiles.
 	dirWatcher *fsnotify.Watcher
 
@@ -96,10 +96,10 @@
 					continue
 				}
 
-				sum := getHashSum(path)
-				if !bytes.Equal(sum, ft.hash) {
+				sum, isDir := getHashSum(path)
+				fmt.Printf("isDir: %v sum: %v, ft.hash: %v\n", isDir, sum, ft.hash)
+				if isDir || !bytes.Equal(sum, ft.hash) {
 					ft.hash = sum
-
 					select {
 					case ft.events <- event:
 						// nothing to do
@@ -141,7 +141,7 @@
 	}
 }
 
-// used only by the worker goroutine
+// drainRetiringTrackers used only by the worker goroutine
 func (wk *worker) drainRetiringTrackers() {
 	// cleanup any trackers that were in the process
 	// of being retired, but didn't get processed due
@@ -156,7 +156,7 @@
 	}
 }
 
-// make a local copy of the set of trackers to avoid contention with callers
+// getTrackers make a local copy of the set of trackers to avoid contention with callers
 // used only by the worker goroutine
 func (wk *worker) getTrackers() map[string]*fileTracker {
 	wk.mu.RLock()
@@ -184,36 +184,34 @@
 
 func (wk *worker) addPath(path string) error {
 	wk.mu.Lock()
+	defer wk.mu.Unlock()
 
 	ft := wk.watchedFiles[path]
 	if ft != nil {
-		wk.mu.Unlock()
 		return fmt.Errorf("path %s is already being watched", path)
 	}
 
+	h, _ := getHashSum(path)
 	ft = &fileTracker{
 		events: make(chan fsnotify.Event),
 		errors: make(chan error),
-		hash:   getHashSum(path),
+		hash:   h,
 	}
-
 	wk.watchedFiles[path] = ft
-	wk.mu.Unlock()
 
 	return nil
 }
 
 func (wk *worker) removePath(path string) error {
 	wk.mu.Lock()
+	defer wk.mu.Unlock()
 
 	ft := wk.watchedFiles[path]
 	if ft == nil {
-		wk.mu.Unlock()
 		return fmt.Errorf("path %s not found", path)
 	}
 
 	delete(wk.watchedFiles, path)
-	wk.mu.Unlock()
 
 	wk.retireTrackerCh <- ft
 	return nil
@@ -241,16 +239,26 @@
 	return nil
 }
 
-// gets the hash of the given file, or nil if there's a problem
-func getHashSum(file string) []byte {
+// getHashSum return the hash of the given file, or nil if there's a problem, or it's a directory.
+func getHashSum(file string) ([]byte, bool) {
 	f, err := os.Open(file)
 	if err != nil {
-		return nil
+		return nil, false
 	}
-	defer f.Close()
-	r := bufio.NewReader(f)
+	defer func() {
+		_ = f.Close()
+	}()
 
+	fi, err := f.Stat()
+	if err != nil {
+		return nil, false
+	}
+	if fi.IsDir() {
+		return nil, true
+	}
+
+	r := bufio.NewReader(f)
 	h := sha256.New()
 	_, _ = io.Copy(h, r)
-	return h.Sum(nil)
+	return h.Sum(nil), false
 }

internal/provider/file/file.go

@@ -13,32 +13,34 @@
 
 	"github.com/fsnotify/fsnotify"
 	"github.com/go-logr/logr"
+	"k8s.io/apimachinery/pkg/util/sets"
 	"sigs.k8s.io/controller-runtime/pkg/healthz"
 
 	egv1a1 "github.com/envoyproxy/gateway/api/v1alpha1"
 	"github.com/envoyproxy/gateway/internal/envoygateway/config"
+	"github.com/envoyproxy/gateway/internal/filewatcher"
 	"github.com/envoyproxy/gateway/internal/message"
+	"github.com/envoyproxy/gateway/internal/utils/path"
 )
 
 type Provider struct {
 	paths          []string
 	logger         logr.Logger
-	notifier       *Notifier
+	watcher        filewatcher.FileWatcher
 	resourcesStore *resourcesStore
 }
 
 func New(svr *config.Server, resources *message.ProviderResources) (*Provider, error) {
 	logger := svr.Logger.Logger
-
-	notifier, err := NewNotifier(logger)
-	if err != nil {
-		return nil, err
+	paths := sets.New[string]()
+	if svr.EnvoyGateway.Provider.Custom.Resource.File != nil {
+		paths.Insert(svr.EnvoyGateway.Provider.Custom.Resource.File.Paths...)
 	}
 
 	return &Provider{
-		paths:          svr.EnvoyGateway.Provider.Custom.Resource.File.Paths,
+		paths:          paths.UnsortedList(),
 		logger:         logger,
-		notifier:       notifier,
+		watcher:        filewatcher.NewWatcher(),
 		resourcesStore: newResourcesStore(svr.EnvoyGateway.Gateway.ControllerName, resources, logger),
 	}, nil
 }
@@ -48,35 +50,50 @@
 }
 
 func (p *Provider) Start(ctx context.Context) error {
-	dirs, files, err := getDirsAndFilesForWatcher(p.paths)
-	if err != nil {
-		return fmt.Errorf("failed to get directories and files for the watcher: %w", err)
-	}
+	defer func() {
+		_ = p.watcher.Close()
+	}()
 
 	// Start runnable servers.
 	go p.startHealthProbeServer(ctx)
 
+	dirs, files := path.ListDirsAndFiles(p.paths)
 	// Initially load resources from paths on host.
-	if err = p.resourcesStore.LoadAndStore(files.UnsortedList(), dirs.UnsortedList()); err != nil {
+	if err := p.resourcesStore.LoadAndStore(files.UnsortedList(), dirs.UnsortedList()); err != nil {
 		return fmt.Errorf("failed to load resources into store: %w", err)
 	}
 
-	// Start watchers in notifier.
-	p.notifier.Watch(ctx, dirs, files)
-	defer p.notifier.Close()
+	// aggregate all path channel into one
+	aggCh := make(chan fsnotify.Event)
+	for _, path := range p.paths {
+		if err := p.watcher.Add(path); err != nil {
+			p.logger.Error(err, "failed to add watch", "path", path)
+		}
+		p.logger.Info("Watching file changed", "path", path)
+		ch := p.watcher.Events(path)
+		go func(c chan fsnotify.Event) {
+			for msg := range c {
+				aggCh <- msg
+			}
+		}(ch)
+	}
 
 	for {
 		select {
 		case <-ctx.Done():
 			return nil
-		case event := <-p.notifier.Events:
+		case event := <-aggCh:
+			p.logger.Info("file changed", "op", event.Op, "name", event.Name)
 			switch event.Op {
 			case fsnotify.Create:
 				dirs.Insert(event.Name)
 				files.Insert(event.Name)
 			case fsnotify.Remove:
 				dirs.Delete(event.Name)
 				files.Delete(event.Name)
+			default:
+				// do nothing
+				continue
 			}
 
 			p.resourcesStore.HandleEvent(event, files.UnsortedList(), dirs.UnsortedList())