From a21413f4eaec49b216c890619d306d9468401740 Mon Sep 17 00:00:00 2001
From: Kate Heddleston <kate@opsolutely.com>
Date: Wed, 17 May 2017 13:03:33 -0700
Subject: [PATCH] NoSuchKey error in S3 is actually '404'

Fixes #571 and #953
---
 moto/s3/models.py        | 4 ++--
 moto/s3/responses.py     | 4 +++-
 tests/test_s3/test_s3.py | 5 +++--
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/moto/s3/models.py b/moto/s3/models.py
index 3cd50050d..b824c4dbf 100644
--- a/moto/s3/models.py
+++ b/moto/s3/models.py
@@ -11,7 +11,7 @@ import six
 from bisect import insort
 from moto.core import BaseBackend, BaseModel
 from moto.core.utils import iso_8601_datetime_with_milliseconds, rfc_1123_datetime
-from .exceptions import BucketAlreadyExists, MissingBucket, MissingKey, InvalidPart, EntityTooSmall
+from .exceptions import BucketAlreadyExists, MissingBucket, InvalidPart, EntityTooSmall
 from .utils import clean_key_name, _VersionedKeyStore
 
 UPLOAD_ID_BYTES = 43
@@ -473,7 +473,7 @@ class S3Backend(BaseBackend):
         if isinstance(key, FakeKey):
             return key
         else:
-            raise MissingKey(key_name=key_name)
+            return None
 
     def initiate_multipart(self, bucket_name, key_name, metadata):
         bucket = self.get_bucket(bucket_name)
diff --git a/moto/s3/responses.py b/moto/s3/responses.py
index fd33c5ead..9a3c00e19 100644
--- a/moto/s3/responses.py
+++ b/moto/s3/responses.py
@@ -12,7 +12,7 @@ from moto.core.responses import _TemplateEnvironmentMixin
 from moto.s3bucket_path.utils import bucket_name_from_url as bucketpath_bucket_name_from_url, parse_key_name as bucketpath_parse_key_name, is_delete_keys as bucketpath_is_delete_keys
 
 
-from .exceptions import BucketAlreadyExists, S3ClientError, InvalidPartOrder
+from .exceptions import BucketAlreadyExists, S3ClientError, MissingKey, InvalidPartOrder
 from .models import s3_backend, get_canned_acl, FakeGrantee, FakeGrant, FakeAcl, FakeKey
 from .utils import bucket_name_from_url, metadata_from_headers
 from xml.dom import minidom
@@ -508,6 +508,8 @@ class ResponseObject(_TemplateEnvironmentMixin):
         version_id = query.get('versionId', [None])[0]
         key = self.backend.get_key(
             bucket_name, key_name, version_id=version_id)
+        if key is None:
+            raise MissingKey(key_name)
         if 'acl' in query:
             template = self.response_template(S3_OBJECT_ACL_RESPONSE)
             return 200, response_headers, template.render(obj=key)
diff --git a/tests/test_s3/test_s3.py b/tests/test_s3/test_s3.py
index de9c6a7de..3907cec6e 100644
--- a/tests/test_s3/test_s3.py
+++ b/tests/test_s3/test_s3.py
@@ -1223,9 +1223,10 @@ def test_boto3_head_object():
     s3.Object('blah', 'hello.txt').meta.client.head_object(
         Bucket='blah', Key='hello.txt')
 
-    with assert_raises(ClientError):
+    with assert_raises(ClientError) as e:
         s3.Object('blah', 'hello2.txt').meta.client.head_object(
             Bucket='blah', Key='hello_bad.txt')
+    e.exception.response['Error']['Code'].should.equal('404')
 
 
 @mock_s3
@@ -1353,7 +1354,7 @@ def test_boto3_delete_markers():
             Bucket=bucket_name,
             Key=key
         )
-        e.response['Error']['Code'].should.equal('NoSuchKey')
+        e.response['Error']['Code'].should.equal('404')
 
     s3.delete_object(
         Bucket=bucket_name,