django1/django/utils/deprecation.py

139 lines
4.9 KiB
Python

import asyncio
import inspect
import warnings
from asgiref.sync import sync_to_async
class RemovedInNextVersionWarning(DeprecationWarning):
pass
class RemovedInDjango40Warning(PendingDeprecationWarning):
pass
class warn_about_renamed_method:
def __init__(self, class_name, old_method_name, new_method_name, deprecation_warning):
self.class_name = class_name
self.old_method_name = old_method_name
self.new_method_name = new_method_name
self.deprecation_warning = deprecation_warning
def __call__(self, f):
def wrapped(*args, **kwargs):
warnings.warn(
"`%s.%s` is deprecated, use `%s` instead." %
(self.class_name, self.old_method_name, self.new_method_name),
self.deprecation_warning, 2)
return f(*args, **kwargs)
return wrapped
class RenameMethodsBase(type):
"""
Handles the deprecation paths when renaming a method.
It does the following:
1) Define the new method if missing and complain about it.
2) Define the old method if missing.
3) Complain whenever an old method is called.
See #15363 for more details.
"""
renamed_methods = ()
def __new__(cls, name, bases, attrs):
new_class = super().__new__(cls, name, bases, attrs)
for base in inspect.getmro(new_class):
class_name = base.__name__
for renamed_method in cls.renamed_methods:
old_method_name = renamed_method[0]
old_method = base.__dict__.get(old_method_name)
new_method_name = renamed_method[1]
new_method = base.__dict__.get(new_method_name)
deprecation_warning = renamed_method[2]
wrapper = warn_about_renamed_method(class_name, *renamed_method)
# Define the new method if missing and complain about it
if not new_method and old_method:
warnings.warn(
"`%s.%s` method should be renamed `%s`." %
(class_name, old_method_name, new_method_name),
deprecation_warning, 2)
setattr(base, new_method_name, old_method)
setattr(base, old_method_name, wrapper(old_method))
# Define the old method as a wrapped call to the new method.
if not old_method and new_method:
setattr(base, old_method_name, wrapper(new_method))
return new_class
class DeprecationInstanceCheck(type):
def __instancecheck__(self, instance):
warnings.warn(
"`%s` is deprecated, use `%s` instead." % (self.__name__, self.alternative),
self.deprecation_warning, 2
)
return super().__instancecheck__(instance)
class MiddlewareMixin:
sync_capable = True
async_capable = True
# RemovedInDjango40Warning: when the deprecation ends, replace with:
# def __init__(self, get_response):
def __init__(self, get_response=None):
self._get_response_none_deprecation(get_response)
self.get_response = get_response
self._async_check()
super().__init__()
def _async_check(self):
"""
If get_response is a coroutine function, turns us into async mode so
a thread is not consumed during a whole request.
"""
if asyncio.iscoroutinefunction(self.get_response):
# Mark the class as async-capable, but do the actual switch
# inside __call__ to avoid swapping out dunder methods
self._is_coroutine = asyncio.coroutines._is_coroutine
def __call__(self, request):
# Exit out to async mode, if needed
if asyncio.iscoroutinefunction(self.get_response):
return self.__acall__(request)
response = None
if hasattr(self, 'process_request'):
response = self.process_request(request)
response = response or self.get_response(request)
if hasattr(self, 'process_response'):
response = self.process_response(request, response)
return response
async def __acall__(self, request):
"""
Async version of __call__ that is swapped in when an async request
is running.
"""
response = None
if hasattr(self, 'process_request'):
response = await sync_to_async(self.process_request)(request)
response = response or await self.get_response(request)
if hasattr(self, 'process_response'):
response = await sync_to_async(self.process_response)(request, response)
return response
def _get_response_none_deprecation(self, get_response):
if get_response is None:
warnings.warn(
'Passing None for the middleware get_response argument is '
'deprecated.',
RemovedInDjango40Warning, stacklevel=3,
)