Add retry_after only to exceptions supporting it

Having retry_after in HTTP response header for 403 status code caused
client to fail with TypeError exception about unexpected keyword
argument. This is related to bug in nova-api. To prevent this kind of
client problems in the future patch adds check to from_response
function to pass retry-after header only to classes that inherit
from RetryAfterException and regression unit tests.

Change-Id: I6bfc8b33eb591d30b3c647397b11100094718e13
Closes-Bug: 1365251
This commit is contained in:
Michal Dulko 2014-09-18 13:07:17 +02:00
parent 4dbf1323cc
commit 310b87ecbb
2 changed files with 75 additions and 12 deletions

View File

@ -105,6 +105,19 @@ class ClientException(Exception):
return formatted_string
class RetryAfterException(ClientException):
"""
The base exception class for ClientExceptions that use Retry-After header.
"""
def __init__(self, *args, **kwargs):
try:
self.retry_after = int(kwargs.pop('retry_after'))
except (KeyError, ValueError):
self.retry_after = 0
super(RetryAfterException, self).__init__(*args, **kwargs)
class BadRequest(ClientException):
"""
HTTP 400 - Bad request: you sent some malformed data.
@ -154,23 +167,15 @@ class Conflict(ClientException):
message = "Conflict"
class OverLimit(ClientException):
class OverLimit(RetryAfterException):
"""
HTTP 413 - Over limit: you're over the API limits for this time period.
"""
http_status = 413
message = "Over limit"
def __init__(self, *args, **kwargs):
try:
self.retry_after = int(kwargs.pop('retry_after'))
except (KeyError, ValueError):
self.retry_after = 0
super(OverLimit, self).__init__(*args, **kwargs)
class RateLimit(OverLimit):
class RateLimit(RetryAfterException):
"""
HTTP 429 - Rate limit: you've sent too many requests for this time period.
"""
@ -220,6 +225,8 @@ def from_response(response, body, url, method=None):
if resp.status_code != 200:
raise exception_from_response(resp, rest.text)
"""
cls = _code_map.get(response.status_code, ClientException)
kwargs = {
'code': response.status_code,
'method': method,
@ -230,7 +237,8 @@ def from_response(response, body, url, method=None):
if response.headers:
kwargs['request_id'] = response.headers.get('x-compute-request-id')
if 'retry-after' in response.headers:
if (issubclass(cls, RetryAfterException) and
'retry-after' in response.headers):
kwargs['retry_after'] = response.headers.get('retry-after')
if body:
@ -245,7 +253,6 @@ def from_response(response, body, url, method=None):
kwargs['message'] = message
kwargs['details'] = details
cls = _code_map.get(response.status_code, ClientException)
return cls(**kwargs)

View File

@ -44,6 +44,32 @@ unknown_error_response = utils.TestResponse({
})
unknown_error_mock_request = mock.Mock(return_value=unknown_error_response)
retry_after_response = utils.TestResponse({
"status_code": 413,
"text": '',
"headers": {
"retry-after": "5"
},
})
retry_after_mock_request = mock.Mock(return_value=retry_after_response)
retry_after_no_headers_response = utils.TestResponse({
"status_code": 413,
"text": '',
})
retry_after_no_headers_mock_request = mock.Mock(
return_value=retry_after_no_headers_response)
retry_after_non_supporting_response = utils.TestResponse({
"status_code": 403,
"text": '',
"headers": {
"retry-after": "5"
},
})
retry_after_non_supporting_mock_request = mock.Mock(
return_value=retry_after_non_supporting_response)
def get_client():
cl = client.HTTPClient("username", "password",
@ -154,3 +180,33 @@ class ClientTest(utils.TestCase):
self.assertIn('Unknown Error', six.text_type(exc))
else:
self.fail('Expected exceptions.ClientException')
@mock.patch.object(requests, "request", retry_after_mock_request)
def test_retry_after_request(self):
cl = get_client()
try:
cl.get("/hi")
except exceptions.OverLimit as exc:
self.assertEqual(5, exc.retry_after)
else:
self.fail('Expected exceptions.OverLimit')
@mock.patch.object(requests, "request",
retry_after_no_headers_mock_request)
def test_retry_after_request_no_headers(self):
cl = get_client()
try:
cl.get("/hi")
except exceptions.OverLimit as exc:
self.assertEqual(0, exc.retry_after)
else:
self.fail('Expected exceptions.OverLimit')
@mock.patch.object(requests, "request",
retry_after_non_supporting_mock_request)
def test_retry_after_request_non_supporting_exc(self):
cl = get_client()
self.assertRaises(exceptions.Forbidden, cl.get, "/hi")