automatic ssl live reload

smtp/fswatcher.go

@@ -0,0 +1,100 @@
+package smtp
+
+import (
+	"math"
+	"path/filepath"
+	"sync"
+	"time"
+
+	"github.com/fsnotify/fsnotify"
+	"gitlab.com/etke.cc/go/logger"
+)
+
+const fsdelay = 100 * time.Millisecond
+
+type FSWatcher struct {
+	watcher *fsnotify.Watcher
+	files   []string
+	log     *logger.Logger
+	mu      sync.Mutex
+	t       map[string]*time.Timer
+}
+
+func NewFSWatcher(files []string, loglevel string) (*FSWatcher, error) {
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		return nil, err
+	}
+
+	for _, file := range files {
+		err = watcher.Add(filepath.Dir(file))
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	fswatcher := &FSWatcher{
+		watcher: watcher,
+		files:   files,
+		log:     logger.New("fs.", loglevel),
+		t:       make(map[string]*time.Timer),
+	}
+
+	return fswatcher, nil
+}
+
+func (w *FSWatcher) watch(handler func(e fsnotify.Event)) {
+	for {
+		select {
+		case err, ok := <-w.watcher.Errors:
+			if !ok {
+				return
+			}
+			w.log.Error("%v", err)
+		case e, ok := <-w.watcher.Events:
+			if !ok {
+				return
+			}
+
+			handler(e)
+		}
+	}
+}
+
+// Start watcher
+func (w *FSWatcher) Start(handler func(e fsnotify.Event)) {
+	w.watch(func(e fsnotify.Event) {
+		var found bool
+		for _, f := range w.files {
+			if f == e.Name {
+				found = true
+			}
+		}
+		if !found {
+			return
+		}
+		w.mu.Lock()
+		t, ok := w.t[e.Name]
+		w.mu.Unlock()
+		if !ok {
+			t = time.AfterFunc(math.MaxInt64, func() {
+				w.log.Info("handling fs event %+v", e)
+				handler(e)
+			})
+			t.Stop()
+
+			w.mu.Lock()
+			w.t[e.Name] = t
+			w.mu.Unlock()
+		}
+		t.Reset(fsdelay)
+	})
+}
+
+// Stop watcher
+func (w *FSWatcher) Stop() {
+	err := w.watcher.Close()
+	if err != nil {
+		w.log.Error("cannot stop fs watcher: %v", err)
+	}
+}