From 68a1e412861c68744e1fbb93f1bd3af964db2dd6 Mon Sep 17 00:00:00 2001
From: Brian Pandola <bpandola@hsdp.io>
Date: Thu, 2 Nov 2017 23:03:54 -0700
Subject: [PATCH] Fix #1318

---
 moto/s3/responses.py     |  2 +-
 tests/test_s3/test_s3.py | 24 ++++++++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/moto/s3/responses.py b/moto/s3/responses.py
index b04cb9496..d5e15aead 100755
--- a/moto/s3/responses.py
+++ b/moto/s3/responses.py
@@ -764,7 +764,7 @@ class ResponseObject(_TemplateEnvironmentMixin):
             return FakeTagging()
 
     def _tagging_from_xml(self, xml):
-        parsed_xml = xmltodict.parse(xml)
+        parsed_xml = xmltodict.parse(xml, force_list={'Tag': True})
 
         tags = []
         for tag in parsed_xml['Tagging']['TagSet']['Tag']:
diff --git a/tests/test_s3/test_s3.py b/tests/test_s3/test_s3.py
index 87668d8b7..32ccd1b9c 100644
--- a/tests/test_s3/test_s3.py
+++ b/tests/test_s3/test_s3.py
@@ -1775,6 +1775,30 @@ def test_boto3_put_object_tagging():
     resp['ResponseMetadata']['HTTPStatusCode'].should.equal(200)
 
 
+@mock_s3
+def test_boto3_put_object_tagging_with_single_tag():
+    s3 = boto3.client('s3', region_name='us-east-1')
+    bucket_name = 'mybucket'
+    key = 'key-with-tags'
+    s3.create_bucket(Bucket=bucket_name)
+
+    s3.put_object(
+        Bucket=bucket_name,
+        Key=key,
+        Body='test'
+    )
+
+    resp = s3.put_object_tagging(
+        Bucket=bucket_name,
+        Key=key,
+        Tagging={'TagSet': [
+            {'Key': 'item1', 'Value': 'foo'}
+        ]}
+    )
+
+    resp['ResponseMetadata']['HTTPStatusCode'].should.equal(200)
+
+
 @mock_s3
 def test_boto3_get_object_tagging():
     s3 = boto3.client('s3', region_name='us-east-1')