notmuch: add internal event loop

worker/notmuch/eventhandlers.go

@@ -0,0 +1,9 @@
+package notmuch
+
+func (w *worker) handleNotmuchEvent(et eventType) error {
+	switch ev := et.(type) {
+	default:
+		_ = ev
+		return errUnsupported
+	}
+}

worker/notmuch/events.go

@@ -0,0 +1,5 @@
+package notmuch
+
+type eventType interface{}
+
+type event struct{}

worker/notmuch/worker.go

@@ -28,6 +28,7 @@ var errUnsupported = fmt.Errorf("unsupported command")
 
 type worker struct {
 	w                   *types.Worker
+	nmEvents            chan eventType
 	query               string
 	uidStore            *uidstore.Store
 	nameQueryMap        map[string]string
@@ -38,23 +39,34 @@ type worker struct {
 
 // NewWorker creates a new maildir worker with the provided worker.
 func NewWorker(w *types.Worker) (types.Backend, error) {
-	return &worker{w: w}, nil
+	events := make(chan eventType, 20)
+	return &worker{w: w,
+		nmEvents: events}, nil
 }
 
 // Run starts the worker's message handling loop.
 func (w *worker) Run() {
 	for {
-		action := <-w.w.Actions
+		select {
+		case action := <-w.w.Actions:
 			msg := w.w.ProcessAction(action)
 			if err := w.handleMessage(msg); err == errUnsupported {
 				w.w.PostMessage(&types.Unsupported{
 					Message: types.RespondTo(msg),
 				}, nil)
+				w.w.Logger.Printf("ProcessAction(%T) unsupported: %v", msg, err)
 			} else if err != nil {
 				w.w.PostMessage(&types.Error{
 					Message: types.RespondTo(msg),
 					Error:   err,
 				}, nil)
+				w.w.Logger.Printf("ProcessAction(%T) failure: %v", msg, err)
+			}
+		case nmEvent := <-w.nmEvents:
+			err := w.handleNotmuchEvent(nmEvent)
+			if err != nil {
+				w.w.Logger.Printf("notmuch event failure: %v", err)
+			}
 		}
 	}
 }