Update SNS get_endpoint_attributes response for Not Found endpoints (#3637)

The response returned for sns.get_endpoint_attributes was not in
sync with the actual response from boto.

Co-authored-by: Antillon, Alejandro <alejandro.antillon@f-secure.com>

moto/sns/exceptions.py

@@ -1,12 +1,24 @@
 from __future__ import unicode_literals
 from moto.core.exceptions import RESTError
 
+NOT_FOUND_ENDPOINT_ERROR = """<ErrorResponse xmlns="http://sns.amazonaws.com/doc/2010-03-31/">
+  <Error>
+    <Type>{{ sender }}</Type>
+    <Code>{{ error_type }}</Code>
+    <Message>{{ message }}</Message>
+  </Error>
+  <RequestId>9dd01905-5012-5f99-8663-4b3ecd0dfaef</RequestId>
+</ErrorResponse>"""
+
 
 class SNSNotFoundError(RESTError):
     code = 404
 
-    def __init__(self, message):
+    def __init__(self, message, **kwargs):
-        super(SNSNotFoundError, self).__init__("NotFound", message)
+        kwargs.setdefault("template", "endpoint_error")
+        kwargs.setdefault("sender", "Sender")
+        self.templates["endpoint_error"] = NOT_FOUND_ENDPOINT_ERROR
+        super(SNSNotFoundError, self).__init__("NotFound", message, **kwargs)
 
 
 class ResourceNotFoundError(RESTError):

moto/sns/models.py

@@ -605,7 +605,7 @@ class SNSBackend(BaseBackend):
         try:
             return self.platform_endpoints[arn]
         except KeyError:
-            raise SNSNotFoundError("Endpoint with arn {0} not found".format(arn))
+            raise SNSNotFoundError("Endpoint does not exist")
 
     def set_endpoint_attributes(self, arn, attributes):
         endpoint = self.get_endpoint(arn)

tests/test_sns/test_application_boto3.py

@@ -5,6 +5,7 @@ from botocore.exceptions import ClientError
 from moto import mock_sns
 import sure  # noqa
 from moto.core import ACCOUNT_ID
+import pytest
 
 
 @mock_sns
@@ -206,6 +207,18 @@ def test_get_endpoint_attributes():
     )
 
 
+@mock_sns
+def test_get_non_existent_endpoint_attributes():
+    conn = boto3.client("sns", region_name="us-east-1")
+    endpoint_arn = "arn:aws:sns:us-east-1:123456789012:endpoint/APNS/my-application/c1f76c42-192a-4e75-b04f-a9268ce2abf3"
+    with pytest.raises(conn.exceptions.NotFoundException) as excinfo:
+        conn.get_endpoint_attributes(EndpointArn=endpoint_arn)
+    error = excinfo.value.response["Error"]
+    error["Type"].should.equal("Sender")
+    error["Code"].should.equal("NotFound")
+    error["Message"].should.equal("Endpoint does not exist")
+
+
 @mock_sns
 def test_get_missing_endpoint_attributes():
     conn = boto3.client("sns", region_name="us-east-1")