Always do a range read for ListWindowsDesktops

Author: zmb3

lib/services/local/desktops.go

@@ -237,39 +237,24 @@ func (s *WindowsDesktopService) ListWindowsDesktops(ctx context.Context, req typ
 		filter.PredicateExpression = expression
 	}
 
-	// do a point-read instead of a range-read if a filter is provided
-	if req.HostID != "" && req.Name != "" {
-		desktop, err := s.getWindowsDesktop(ctx, req.Name, req.HostID)
-		if trace.IsNotFound(err) {
-			return &types.ListWindowsDesktopsResponse{}, nil
-		} else if err != nil {
-			return nil, trace.Wrap(err)
-		}
-
-		match, err := services.MatchResourceByFilters(desktop, filter, nil /* ignore dup matches */)
-		if err != nil {
-			return nil, trace.Wrap(err)
-		}
-
-		if !match {
-			return &types.ListWindowsDesktopsResponse{}, nil
-		}
-
-		return &types.ListWindowsDesktopsResponse{
-			Desktops: []types.WindowsDesktop{desktop},
-		}, nil
+	var rangeStart, rangeEnd backend.Key
+	switch {
+	case req.Name != "" && req.HostID != "":
+		rangeStart = backend.NewKey(windowsDesktopsPrefix, req.HostID, req.Name)
+		rangeEnd = rangeStart
+	case req.HostID != "":
+		rangeStart = backend.ExactKey(windowsDesktopsPrefix, req.HostID)
+		rangeEnd = backend.RangeEnd(rangeStart)
+	default:
+		rangeStart = backend.ExactKey(windowsDesktopsPrefix)
+		rangeEnd = backend.RangeEnd(rangeStart)
 	}
 
-	var rangeStart, rangeEnd backend.Key
-	if req.HostID != "" && req.Name == "" {
-		rangeStart = backend.NewKey(windowsDesktopsPrefix, req.HostID)
-		if req.StartKey != "" {
-			rangeStart = backend.NewKey(windowsDesktopsPrefix, req.StartKey)
+	if req.StartKey != "" {
+		k := backend.NewKey(windowsDesktopsPrefix, req.StartKey)
+		if k.Compare(rangeStart) > 0 {
+			rangeStart = k
 		}
-		rangeEnd = backend.RangeEnd(rangeStart)
-	} else {
-		rangeStart = backend.NewKey(windowsDesktopsPrefix, req.StartKey)
-		rangeEnd = backend.RangeEnd(backend.ExactKey(windowsDesktopsPrefix))
 	}
 
 	// Get most limit+1 results to determine if there will be a next key.