103 lines
3.3 KiB
Python
103 lines
3.3 KiB
Python
# Licensed to the Apache Software Foundation (ASF) under one or more
|
|
# contributor license agreements. See the NOTICE file distributed with
|
|
# this work for additional information regarding copyright ownership.
|
|
# The ASF licenses this file to You under the Apache License, Version 2.0
|
|
# (the "License"); you may not use this file except in compliance with
|
|
# the License. You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
|
|
import time
|
|
|
|
from email.utils import parsedate_tz, mktime_tz
|
|
|
|
__all__ = [
|
|
'BaseHTTPError',
|
|
'RateLimitReachedError',
|
|
|
|
'exception_from_message'
|
|
]
|
|
|
|
|
|
class BaseHTTPError(Exception):
|
|
|
|
"""
|
|
The base exception class for all HTTP related exceptions.
|
|
"""
|
|
|
|
def __init__(self, code, message, headers=None):
|
|
self.code = code
|
|
self.message = message
|
|
self.headers = headers
|
|
# preserve old exception behavior for tests that
|
|
# look for e.args[0]
|
|
super(BaseHTTPError, self).__init__(message)
|
|
|
|
def __str__(self):
|
|
return self.message
|
|
|
|
|
|
class RateLimitReachedError(BaseHTTPError):
|
|
"""
|
|
HTTP 429 - Rate limit: you've sent too many requests for this time period.
|
|
"""
|
|
code = 429
|
|
message = '%s Rate limit exceeded' % (code)
|
|
|
|
def __init__(self, *args, **kwargs):
|
|
headers = kwargs.pop('headers', None)
|
|
super(RateLimitReachedError, self).__init__(self.code,
|
|
self.message,
|
|
headers)
|
|
if self.headers is not None:
|
|
self.retry_after = float(self.headers.get('retry-after', 0))
|
|
else:
|
|
self.retry_after = 0
|
|
|
|
|
|
_error_classes = [RateLimitReachedError]
|
|
_code_map = dict((c.code, c) for c in _error_classes)
|
|
|
|
|
|
def exception_from_message(code, message, headers=None):
|
|
"""
|
|
Return an instance of BaseHTTPException or subclass based on response code.
|
|
|
|
If headers include Retry-After, RFC 2616 says that its value may be one of
|
|
two formats: HTTP-date or delta-seconds, for example:
|
|
|
|
Retry-After: Fri, 31 Dec 1999 23:59:59 GMT
|
|
Retry-After: 120
|
|
|
|
If Retry-After comes in HTTP-date, it'll be translated to a positive
|
|
delta-seconds value when passing it to the exception constructor.
|
|
|
|
Also, RFC 2616 says that Retry-After isn't just only applicable to 429
|
|
HTTP status, but also to other responses, like 503 and 3xx.
|
|
|
|
Usage::
|
|
raise exception_from_message(code=self.status,
|
|
message=self.parse_error(),
|
|
headers=self.headers)
|
|
"""
|
|
kwargs = {
|
|
'code': code,
|
|
'message': message,
|
|
'headers': headers
|
|
}
|
|
|
|
if headers and 'retry-after' in headers:
|
|
http_date = parsedate_tz(headers['retry-after'])
|
|
if http_date is not None:
|
|
# Convert HTTP-date to delay-seconds
|
|
delay = max(0, int(mktime_tz(http_date) - time.time()))
|
|
headers['retry-after'] = str(delay)
|
|
cls = _code_map.get(code, BaseHTTPError)
|
|
return cls(**kwargs)
|