Add sns.untag_resource

IMPLEMENTATION_COVERAGE.md

@@ -5866,7 +5866,7 @@
 - [ ] update_job
 
 ## sns
-55% implemented
+58% implemented
 - [ ] add_permission
 - [ ] check_if_phone_number_is_opted_out
 - [ ] confirm_subscription
@@ -5899,7 +5899,7 @@
 - [X] subscribe
 - [x] tag_resource
 - [X] unsubscribe
-- [ ] untag_resource
+- [x] untag_resource
 
 ## sqs
 65% implemented

moto/sns/models.py

@@ -521,6 +521,13 @@ class SNSBackend(BaseBackend):
 
         self.topics[resource_arn]._tags = updated_tags
 
+    def untag_resource(self, resource_arn, tag_keys):
+        if resource_arn not in self.topics:
+            raise ResourceNotFoundError
+
+        for key in tag_keys:
+            self.topics[resource_arn]._tags.pop(key, None)
+
 
 sns_backends = {}
 for region in Session().get_available_regions('sns'):

moto/sns/responses.py

@@ -712,6 +712,14 @@ class SNSResponse(BaseResponse):
 
         return self.response_template(TAG_RESOURCE_TEMPLATE).render()
 
+    def untag_resource(self):
+        arn = self._get_param('ResourceArn')
+        tag_keys = self._get_multi_param('TagKeys.member')
+
+        self.backend.untag_resource(arn, tag_keys)
+
+        return self.response_template(UNTAG_RESOURCE_TEMPLATE).render()
+
 
 CREATE_TOPIC_TEMPLATE = """<CreateTopicResponse xmlns="http://sns.amazonaws.com/doc/2010-03-31/">
      <CreateTopicResult>
@@ -1116,3 +1124,10 @@ TAG_RESOURCE_TEMPLATE = """<TagResourceResponse xmlns="http://sns.amazonaws.com/
         <RequestId>fd4ab1da-692f-50a7-95ad-e7c665877d98</RequestId>
     </ResponseMetadata>
 </TagResourceResponse>"""
+
+UNTAG_RESOURCE_TEMPLATE = """<UntagResourceResponse xmlns="http://sns.amazonaws.com/doc/2010-03-31/">
+    <UntagResourceResult/>
+    <ResponseMetadata>
+        <RequestId>14eb7b1a-4cbd-5a56-80db-2d06412df769</RequestId>
+    </ResponseMetadata>
+</UntagResourceResponse>"""

tests/test_sns/test_topics_boto3.py

@@ -297,6 +297,52 @@ def test_tag_topic():
     ])
 
 
+@mock_sns
+def test_untag_topic():
+    conn = boto3.client('sns', region_name = 'us-east-1')
+    response = conn.create_topic(
+        Name = 'some-topic-with-tags',
+        Tags = [
+            {
+                'Key': 'tag_key_1',
+                'Value': 'tag_value_1'
+            },
+            {
+                'Key': 'tag_key_2',
+                'Value': 'tag_value_2'
+            }
+        ]
+    )
+    topic_arn = response['TopicArn']
+
+    conn.untag_resource(
+        ResourceArn = topic_arn,
+        TagKeys = [
+            'tag_key_1'
+        ]
+    )
+    conn.list_tags_for_resource(ResourceArn = topic_arn)['Tags'].should.equal([
+        {
+            'Key': 'tag_key_2',
+            'Value': 'tag_value_2'
+        }
+    ])
+
+    # removing a non existing tag should not raise any error
+    conn.untag_resource(
+        ResourceArn = topic_arn,
+        TagKeys = [
+            'not-existing-tag'
+        ]
+    )
+    conn.list_tags_for_resource(ResourceArn = topic_arn)['Tags'].should.equal([
+        {
+            'Key': 'tag_key_2',
+            'Value': 'tag_value_2'
+        }
+    ])
+
+
 @mock_sns
 def test_list_tags_for_resource_error():
     conn = boto3.client('sns', region_name = 'us-east-1')
@@ -361,3 +407,27 @@ def test_tag_resource_errors():
             'Value': 'tag_value_X'
         }
     ])
+
+
+@mock_sns
+def test_untag_resource_error():
+    conn = boto3.client('sns', region_name = 'us-east-1')
+    conn.create_topic(
+        Name = 'some-topic-with-tags',
+        Tags = [
+            {
+                'Key': 'tag_key_1',
+                'Value': 'tag_value_X'
+            }
+        ]
+    )
+
+    conn.untag_resource.when.called_with(
+        ResourceArn = 'not-existing-topic',
+        TagKeys = [
+            'tag_key_1'
+        ]
+    ).should.throw(
+        ClientError,
+        'Resource does not exist'
+    )