1 files changed, 4 insertions, 5 deletions
diff --git a/go/topology/topology_map.go b/go/topology/topology_map.go
index d6400c988..6a1423ca8 100644
--- a/go/topology/topology_map.go
+++ b/go/topology/topology_map.go
@@ -1,7 +1,5 @@
 package topology
 
-import ()
-
 func (t *Topology) ToMap() interface{} {
 	m := make(map[string]interface{})
 	m["Max"] = t.GetMaxVolumeCount()
@@ -13,10 +11,11 @@ func (t *Topology) ToMap() interface{} {
 	}
 	m["DataCenters"] = dcs
 	var layouts []interface{}
-	for _, c := range t.collectionMap {
-		for _, layout := range c.storageType2VolumeLayout {
+	for _, col := range t.collectionMap.Items {
+		c := col.(*Collection)
+		for _, layout := range c.storageType2VolumeLayout.Items {
 			if layout != nil {
-				tmp := layout.ToMap()
+				tmp := layout.(*VolumeLayout).ToMap()
 				tmp["collection"] = c.Name
 				layouts = append(layouts, tmp)
 			}