s3api: Translate 503 to S3-style 503s

...instead of logging tracebacks about unexpected status codes.

Change-Id: Iadb0a40092b8347eb5c04785cc14d1324cc9396f
(cherry picked from commit 7bb7da6d2d)

swift/common/middleware/s3api/s3request.py

@@ -32,7 +32,8 @@ from swift.common.http import HTTP_OK, HTTP_CREATED, HTTP_ACCEPTED, \
     HTTP_CONFLICT, HTTP_UNPROCESSABLE_ENTITY, HTTP_REQUEST_ENTITY_TOO_LARGE, \
     HTTP_PARTIAL_CONTENT, HTTP_NOT_MODIFIED, HTTP_PRECONDITION_FAILED, \
     HTTP_REQUESTED_RANGE_NOT_SATISFIABLE, HTTP_LENGTH_REQUIRED, \
-    HTTP_BAD_REQUEST, HTTP_REQUEST_TIMEOUT, is_success
+    HTTP_BAD_REQUEST, HTTP_REQUEST_TIMEOUT, HTTP_SERVICE_UNAVAILABLE, \
+    is_success
 
 from swift.common.constraints import check_utf8
 from swift.proxy.controllers.base import get_container_info, \
@@ -51,7 +52,8 @@ from swift.common.middleware.s3api.s3response import AccessDenied, \
     InternalError, NoSuchBucket, NoSuchKey, PreconditionFailed, InvalidRange, \
     MissingContentLength, InvalidStorageClass, S3NotImplemented, InvalidURI, \
     MalformedXML, InvalidRequest, RequestTimeout, InvalidBucketName, \
-    BadDigest, AuthorizationHeaderMalformed, AuthorizationQueryParametersError
+    BadDigest, AuthorizationHeaderMalformed, \
+    AuthorizationQueryParametersError, ServiceUnavailable
 from swift.common.middleware.s3api.exception import NotS3Request, \
     BadSwiftRequest
 from swift.common.middleware.s3api.utils import utf8encode, \
@@ -1358,6 +1360,8 @@ class S3Request(swob.Request):
                 **self.signature_does_not_match_kwargs())
         if status == HTTP_FORBIDDEN:
             raise AccessDenied()
+        if status == HTTP_SERVICE_UNAVAILABLE:
+            raise ServiceUnavailable()
 
         raise InternalError('unexpected status code %d' % status)
 

test/unit/common/middleware/s3api/test_bucket.py

@@ -78,6 +78,9 @@ class TestS3ApiBucket(S3ApiTestCase):
             'HEAD', '/v1/AUTH_test/junk', swob.HTTPNoContent, {}, None)
         self.swift.register(
             'HEAD', '/v1/AUTH_test/nojunk', swob.HTTPNotFound, {}, None)
+        self.swift.register(
+            'HEAD', '/v1/AUTH_test/unavailable', swob.HTTPServiceUnavailable,
+            {}, None)
         self.swift.register(
             'GET', '/v1/AUTH_test/junk', swob.HTTPOk,
             {'Content-Type': 'application/json'}, object_list)
@@ -121,6 +124,15 @@ class TestS3ApiBucket(S3ApiTestCase):
         self.assertEqual(status.split()[0], '404')
         self.assertEqual(body, '')  # sanity
 
+    def test_bucket_HEAD_503(self):
+        req = Request.blank('/unavailable',
+                            environ={'REQUEST_METHOD': 'HEAD'},
+                            headers={'Authorization': 'AWS test:tester:hmac',
+                                     'Date': self.get_date_header()})
+        status, headers, body = self.call_s3api(req)
+        self.assertEqual(status.split()[0], '503')
+        self.assertEqual(body, b'')  # sanity
+
     def test_bucket_HEAD_slash(self):
         req = Request.blank('/junk/',
                             environ={'REQUEST_METHOD': 'HEAD'},
@@ -145,6 +157,9 @@ class TestS3ApiBucket(S3ApiTestCase):
         self.assertEqual(code, 'AccessDenied')
         code = self._test_method_error('GET', '/bucket', swob.HTTPNotFound)
         self.assertEqual(code, 'NoSuchBucket')
+        code = self._test_method_error('GET', '/bucket',
+                                       swob.HTTPServiceUnavailable)
+        self.assertEqual(code, 'ServiceUnavailable')
         code = self._test_method_error('GET', '/bucket', swob.HTTPServerError)
         self.assertEqual(code, 'InternalError')
 
@@ -604,6 +619,9 @@ class TestS3ApiBucket(S3ApiTestCase):
         self.assertEqual(code, 'BucketAlreadyExists')
         code = self._test_method_error('PUT', '/bucket', swob.HTTPServerError)
         self.assertEqual(code, 'InternalError')
+        code = self._test_method_error(
+            'PUT', '/bucket', swob.HTTPServiceUnavailable)
+        self.assertEqual(code, 'ServiceUnavailable')
         code = self._test_method_error(
             'PUT', '/bucket+bucket', swob.HTTPCreated)
         self.assertEqual(code, 'InvalidBucketName')

test/unit/common/middleware/s3api/test_obj.py

@@ -159,7 +159,7 @@ class TestS3ApiObj(S3ApiTestCase):
         self.swift.register('HEAD', '/v1/AUTH_test/bucket/object',
                             swob.HTTPServiceUnavailable, {}, None)
         status, headers, body = self.call_s3api(req)
-        self.assertEqual(status.split()[0], '500')
+        self.assertEqual(status.split()[0], '503')
         self.assertEqual(body, '')  # sanity
 
     def test_object_HEAD(self):
@@ -279,7 +279,7 @@ class TestS3ApiObj(S3ApiTestCase):
         self.assertEqual(code, 'PreconditionFailed')
         code = self._test_method_error('GET', '/bucket/object',
                                        swob.HTTPServiceUnavailable)
-        self.assertEqual(code, 'InternalError')
+        self.assertEqual(code, 'ServiceUnavailable')
 
     @s3acl
     def test_object_GET(self):
@@ -396,7 +396,7 @@ class TestS3ApiObj(S3ApiTestCase):
         self.assertEqual(code, 'InternalError')
         code = self._test_method_error('PUT', '/bucket/object',
                                        swob.HTTPServiceUnavailable)
-        self.assertEqual(code, 'InternalError')
+        self.assertEqual(code, 'ServiceUnavailable')
         code = self._test_method_error('PUT', '/bucket/object',
                                        swob.HTTPCreated,
                                        {'X-Amz-Copy-Source': ''})
@@ -956,7 +956,7 @@ class TestS3ApiObj(S3ApiTestCase):
         self.assertEqual(code, 'InternalError')
         code = self._test_method_error('DELETE', '/bucket/object',
                                        swob.HTTPServiceUnavailable)
-        self.assertEqual(code, 'InternalError')
+        self.assertEqual(code, 'ServiceUnavailable')
 
         with patch(
                 'swift.common.middleware.s3api.s3request.get_container_info',