From 8d2ceea5f1a9b5dd63d9f94d3bd3c891d2295510 Mon Sep 17 00:00:00 2001
From: Rickard von Essen <rickard.von.essen@gmail.com>
Date: Thu, 1 Dec 2016 20:43:15 +0100
Subject: [PATCH] builder/amazon: crash on tagging snapshot when snapshot_tags
 is unset

Closes #4238
---
 builder/amazon/common/step_create_tags.go | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/builder/amazon/common/step_create_tags.go b/builder/amazon/common/step_create_tags.go
index a8234b5d3..87ce08840 100644
--- a/builder/amazon/common/step_create_tags.go
+++ b/builder/amazon/common/step_create_tags.go
@@ -96,10 +96,12 @@ func (s *StepCreateTags) Run(state multistep.StateBag) multistep.StepAction {
 			}
 
 			// Override tags on snapshots
-			_, err = regionconn.CreateTags(&ec2.CreateTagsInput{
-				Resources: snapshotIds,
-				Tags:      snapshotTags,
-			})
+			if len(snapshotTags) > 0 {
+				_, err = regionconn.CreateTags(&ec2.CreateTagsInput{
+					Resources: snapshotIds,
+					Tags:      snapshotTags,
+				})
+			}
 			if err == nil {
 				return true, nil
 			}