1
0
mirror of https://github.com/django/django.git synced 2025-11-07 07:15:35 +00:00
Files
django/django/utils/deprecation.py
2025-09-17 15:17:05 -03:00

331 lines
12 KiB
Python

import functools
import inspect
import os
import warnings
from collections import Counter
from asgiref.sync import iscoroutinefunction, markcoroutinefunction, sync_to_async
import django
@functools.cache
def django_file_prefixes():
try:
file = django.__file__
except AttributeError:
return ()
return (os.path.dirname(file),)
class RemovedInNextVersionWarning(DeprecationWarning):
pass
class RemovedInDjango70Warning(PendingDeprecationWarning):
pass
RemovedAfterNextVersionWarning = RemovedInDjango70Warning
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 wrapper(*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 wrapper
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
def deprecate_posargs(deprecation_warning, remappable_names, /):
"""
Function/method decorator to deprecate some or all positional arguments.
The decorated function will map any positional arguments after the ``*`` to
the corresponding keyword arguments and issue a deprecation warning.
The decorator takes two arguments: a RemovedInDjangoXXWarning warning
category and a list of parameter names that have been changed from
positional-or-keyword to keyword-only, in their original positional order.
Works on both functions and methods. To apply to a class constructor,
decorate its __init__() method. To apply to a staticmethod or classmethod,
use @deprecate_posargs after @staticmethod or @classmethod.
Example: to deprecate passing option1 or option2 as posargs, change::
def some_func(request, option1, option2=True):
...
to::
@deprecate_posargs(RemovedInDjangoXXWarning, ["option1", "option2"])
def some_func(request, *, option1, option2=True):
...
After the deprecation period, remove the decorator (but keep the ``*``)::
def some_func(request, *, option1, option2=True):
...
Caution: during the deprecation period, do not add any new *positional*
parameters or change the remaining ones. For example, this attempt to add a
new param would break code using the deprecated posargs::
@deprecate_posargs(RemovedInDjangoXXWarning, ["option1", "option2"])
def some_func(request, wrong_new_param=None, *, option1, option2=True):
# Broken: existing code may pass a value intended as option1 in the
# wrong_new_param position.
...
However, it's acceptable to add new *keyword-only* parameters and to
re-order the existing ones, so long as the list passed to
@deprecate_posargs is kept in the original posargs order. This change will
work without breaking existing code::
@deprecate_posargs(RemovedInDjangoXXWarning, ["option1", "option2"])
def some_func(request, *, new_param=None, option2=True, option1):
...
The @deprecate_posargs decorator adds a small amount of overhead. In most
cases it won't be significant, but use with care in performance-critical
code paths.
"""
def decorator(func):
if isinstance(func, type):
raise TypeError(
"@deprecate_posargs cannot be applied to a class. (Apply it "
"to the __init__ method.)"
)
if isinstance(func, classmethod):
raise TypeError("Apply @classmethod before @deprecate_posargs.")
if isinstance(func, staticmethod):
raise TypeError("Apply @staticmethod before @deprecate_posargs.")
params = inspect.signature(func).parameters
num_by_kind = Counter(param.kind for param in params.values())
if num_by_kind[inspect.Parameter.VAR_POSITIONAL] > 0:
raise TypeError(
"@deprecate_posargs() cannot be used with variable positional `*args`."
)
num_positional_params = (
num_by_kind[inspect.Parameter.POSITIONAL_ONLY]
+ num_by_kind[inspect.Parameter.POSITIONAL_OR_KEYWORD]
)
num_keyword_only_params = num_by_kind[inspect.Parameter.KEYWORD_ONLY]
if num_keyword_only_params < 1:
raise TypeError(
"@deprecate_posargs() requires at least one keyword-only parameter "
"(after a `*` entry in the parameters list)."
)
if any(
name not in params or params[name].kind != inspect.Parameter.KEYWORD_ONLY
for name in remappable_names
):
raise TypeError(
"@deprecate_posargs() requires all remappable_names to be "
"keyword-only parameters."
)
num_remappable_args = len(remappable_names)
max_positional_args = num_positional_params + num_remappable_args
func_name = func.__name__
if func_name == "__init__":
# In the warning, show "ClassName()" instead of "__init__()".
# The class isn't defined yet, but its name is in __qualname__.
# Some examples of __qualname__:
# - ClassName.__init__
# - Nested.ClassName.__init__
# - MyTests.test_case.<locals>.ClassName.__init__
local_name = func.__qualname__.rsplit("<locals>.", 1)[-1]
class_name = local_name.replace(".__init__", "")
func_name = class_name
def remap_deprecated_args(args, kwargs):
"""
Move deprecated positional args to kwargs and issue a warning.
Return updated (args, kwargs).
"""
if (num_positional_args := len(args)) > max_positional_args:
raise TypeError(
f"{func_name}() takes at most {max_positional_args} positional "
f"argument(s) (including {num_remappable_args} deprecated) but "
f"{num_positional_args} were given."
)
# Identify which of the _potentially remappable_ params are
# actually _being remapped_ in this particular call.
remapped_names = remappable_names[
: num_positional_args - num_positional_params
]
conflicts = set(remapped_names) & set(kwargs)
if conflicts:
# Report duplicate names in the original parameter order.
conflicts_str = ", ".join(
f"'{name}'" for name in remapped_names if name in conflicts
)
raise TypeError(
f"{func_name}() got both deprecated positional and keyword "
f"argument values for {conflicts_str}."
)
# Do the remapping.
remapped_kwargs = dict(
zip(remapped_names, args[num_positional_params:], strict=True)
)
remaining_args = args[:num_positional_params]
updated_kwargs = kwargs | remapped_kwargs
# Issue the deprecation warning.
remapped_names_str = ", ".join(f"'{name}'" for name in remapped_names)
warnings.warn(
f"Passing positional argument(s) {remapped_names_str} to {func_name}() "
"is deprecated. Use keyword arguments instead.",
deprecation_warning,
skip_file_prefixes=django_file_prefixes(),
)
return remaining_args, updated_kwargs
if iscoroutinefunction(func):
@functools.wraps(func)
async def wrapper(*args, **kwargs):
if len(args) > num_positional_params:
args, kwargs = remap_deprecated_args(args, kwargs)
return await func(*args, **kwargs)
else:
@functools.wraps(func)
def wrapper(*args, **kwargs):
if len(args) > num_positional_params:
args, kwargs = remap_deprecated_args(args, kwargs)
return func(*args, **kwargs)
return wrapper
return decorator
class MiddlewareMixin:
sync_capable = True
async_capable = True
def __init__(self, get_response):
if get_response is None:
raise ValueError("get_response must be provided.")
self.get_response = get_response
# If get_response is a coroutine function, turns us into async mode so
# a thread is not consumed during a whole request.
self.async_mode = iscoroutinefunction(self.get_response)
if self.async_mode:
# Mark the class as async-capable, but do the actual switch inside
# __call__ to avoid swapping out dunder methods.
markcoroutinefunction(self)
super().__init__()
def __repr__(self):
return "<%s get_response=%s>" % (
self.__class__.__qualname__,
getattr(
self.get_response,
"__qualname__",
self.get_response.__class__.__name__,
),
)
def __call__(self, request):
# Exit out to async mode, if needed
if self.async_mode:
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,
thread_sensitive=True,
)(request)
response = response or await self.get_response(request)
if hasattr(self, "process_response"):
response = await sync_to_async(
self.process_response,
thread_sensitive=True,
)(request, response)
return response