1
0
mirror of https://github.com/django/django.git synced 2024-12-23 01:25:58 +00:00

Fixed #6371 - several decorators don't work with bound methods.

This involved changing the way the internal function
decorator_from_middleware works slightly, breaking some code that relied on
the old behaviour.  As a result, it is much simpler, but cache_page has been
made slightly more complex to cope with the change.



git-svn-id: http://code.djangoproject.com/svn/django/trunk@11586 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Luke Plant 2009-09-21 22:31:51 +00:00
parent d56c1ab7f0
commit afeafcd492
3 changed files with 155 additions and 53 deletions

View File

@ -2,60 +2,88 @@
import types
try:
from functools import wraps
from functools import wraps, update_wrapper
except ImportError:
from django.utils.functional import wraps # Python 2.3, 2.4 fallback.
from django.utils.functional import wraps, update_wrapper # Python 2.3, 2.4 fallback.
class MethodDecoratorAdaptor(object):
"""
Generic way of creating decorators that adapt to being
used on methods
"""
def __init__(self, decorator, func):
update_wrapper(self, func)
# NB: update the __dict__ first, *then* set
# our own .func and .decorator, in case 'func' is actually
# another MethodDecoratorAdaptor object, which has its
# 'func' and 'decorator' attributes in its own __dict__
self.decorator = decorator
self.func = func
def __call__(self, *args, **kwargs):
return self.decorator(self.func)(*args, **kwargs)
def __get__(self, instance, owner):
return self.decorator(self.func.__get__(instance, owner))
def _get_name(self):
return self.func.__name__
def _get_doc(self):
return self.func.__doc__
def auto_adapt_to_methods(decorator):
"""Allows you to use the same decorator on methods and functions,
hiding the self argument from the decorator."""
def adapt(func):
return MethodDecoratorAdaptor(decorator, func)
return wraps(decorator)(adapt)
def decorator_from_middleware_with_args(middleware_class):
"""
Like decorator_from_middleware, but returns a function
that accepts the arguments to be passed to the middleware_class.
Use like::
cache_page = decorator_from_middleware(CacheMiddleware)
# ...
@cache_page(3600)
def my_view(request):
# ...
"""
return make_middleware_decorator(middleware_class)
def decorator_from_middleware(middleware_class):
"""
Given a middleware class (not an instance), returns a view decorator. This
lets you use middleware functionality on a per-view basis.
lets you use middleware functionality on a per-view basis. The middleware
is created with no params passed.
"""
def _decorator_from_middleware(*args, **kwargs):
# For historical reasons, these "decorators" are also called as
# dec(func, *args) instead of dec(*args)(func). We handle both forms
# for backwards compatibility.
has_func = True
try:
view_func = kwargs.pop('view_func')
except KeyError:
if len(args):
view_func, args = args[0], args[1:]
else:
has_func = False
if not (has_func and isinstance(view_func, types.FunctionType)):
# We are being called as a decorator.
if has_func:
args = (view_func,) + args
middleware = middleware_class(*args, **kwargs)
return make_middleware_decorator(middleware_class)()
def decorator_func(fn):
return _decorator_from_middleware(fn, *args, **kwargs)
return decorator_func
middleware = middleware_class(*args, **kwargs)
def _wrapped_view(request, *args, **kwargs):
if hasattr(middleware, 'process_request'):
result = middleware.process_request(request)
if result is not None:
return result
if hasattr(middleware, 'process_view'):
result = middleware.process_view(request, view_func, args, kwargs)
if result is not None:
return result
try:
response = view_func(request, *args, **kwargs)
except Exception, e:
if hasattr(middleware, 'process_exception'):
result = middleware.process_exception(request, e)
def make_middleware_decorator(middleware_class):
def _make_decorator(*m_args, **m_kwargs):
middleware = middleware_class(*m_args, **m_kwargs)
def _decorator(view_func):
def _wrapped_view(request, *args, **kwargs):
if hasattr(middleware, 'process_request'):
result = middleware.process_request(request)
if result is not None:
return result
raise
if hasattr(middleware, 'process_response'):
result = middleware.process_response(request, response)
if result is not None:
return result
return response
return wraps(view_func)(_wrapped_view)
return _decorator_from_middleware
if hasattr(middleware, 'process_view'):
result = middleware.process_view(request, view_func, args, kwargs)
if result is not None:
return result
try:
response = view_func(request, *args, **kwargs)
except Exception, e:
if hasattr(middleware, 'process_exception'):
result = middleware.process_exception(request, e)
if result is not None:
return result
raise
if hasattr(middleware, 'process_response'):
result = middleware.process_response(request, response)
if result is not None:
return result
return response
return wraps(view_func)(_wrapped_view)
return auto_adapt_to_methods(_decorator)
return _make_decorator

View File

@ -16,11 +16,22 @@ try:
except ImportError:
from django.utils.functional import wraps # Python 2.3, 2.4 fallback.
from django.utils.decorators import decorator_from_middleware
from django.utils.decorators import decorator_from_middleware_with_args, auto_adapt_to_methods
from django.utils.cache import patch_cache_control, add_never_cache_headers
from django.middleware.cache import CacheMiddleware
cache_page = decorator_from_middleware(CacheMiddleware)
def cache_page(*args, **kwargs):
# We need backwards compatibility with code which spells it this way:
# def my_view(): pass
# my_view = cache_page(123, my_view)
# and this way:
# my_view = cache_page(123)(my_view)
timeout = args[0]
if len(args) > 1:
fn = args[1]
return decorator_from_middleware_with_args(CacheMiddleware)(timeout)(fn)
else:
return decorator_from_middleware_with_args(CacheMiddleware)(timeout)
def cache_control(**kwargs):
@ -33,7 +44,7 @@ def cache_control(**kwargs):
return wraps(viewfunc)(_cache_controlled)
return _cache_controller
return auto_adapt_to_methods(_cache_controller)
def never_cache(view_func):
"""
@ -45,3 +56,4 @@ def never_cache(view_func):
add_never_cache_headers(response)
return response
return wraps(view_func)(_wrapped_view_func)
never_cache = auto_adapt_to_methods(never_cache)

View File

@ -1,11 +1,16 @@
from unittest import TestCase
from sys import version_info
try:
from functools import wraps
except ImportError:
from django.utils.functional import wraps # Python 2.3, 2.4 fallback.
from django.http import HttpResponse
from django.http import HttpResponse, HttpRequest
from django.utils.functional import allow_lazy, lazy, memoize
from django.views.decorators.http import require_http_methods, require_GET, require_POST
from django.views.decorators.vary import vary_on_headers, vary_on_cookie
from django.views.decorators.cache import cache_page, never_cache, cache_control
from django.utils.decorators import auto_adapt_to_methods
from django.contrib.auth.decorators import login_required, permission_required, user_passes_test
from django.contrib.admin.views.decorators import staff_member_required
@ -84,4 +89,61 @@ class DecoratorsTest(TestCase):
response = callback(request)
self.assertEqual(response, ['test2', 'test1'])
def test_cache_page_new_style(self):
"""
Test that we can call cache_page the new way
"""
def my_view(request):
return "response"
my_view_cached = cache_page(123)(my_view)
self.assertEqual(my_view_cached(HttpRequest()), "response")
def test_cache_page_old_style(self):
"""
Test that we can call cache_page the old way
"""
def my_view(request):
return "response"
my_view_cached = cache_page(123, my_view)
self.assertEqual(my_view_cached(HttpRequest()), "response")
class MethodDecoratorAdapterTests(TestCase):
def test_auto_adapt_to_methods(self):
"""
Test that auto_adapt_to_methods actually works.
"""
# Need 2 decorators with auto_adapt_to_methods,
# to check it plays nicely with composing itself.
def my_decorator(func):
def wrapped(*args, **kwargs):
# need to ensure that the first arg isn't 'self'
self.assertEqual(args[0], "test")
return "my_decorator:" + func(*args, **kwargs)
wrapped.my_decorator_custom_attribute = True
return wraps(func)(wrapped)
my_decorator = auto_adapt_to_methods(my_decorator)
def my_decorator2(func):
def wrapped(*args, **kwargs):
# need to ensure that the first arg isn't 'self'
self.assertEqual(args[0], "test")
return "my_decorator2:" + func(*args, **kwargs)
wrapped.my_decorator2_custom_attribute = True
return wraps(func)(wrapped)
my_decorator2 = auto_adapt_to_methods(my_decorator2)
class MyClass(object):
def my_method(self, *args, **kwargs):
return "my_method:%r %r" % (args, kwargs)
my_method = my_decorator2(my_decorator(my_method))
obj = MyClass()
self.assertEqual(obj.my_method("test", 123, name='foo'),
"my_decorator2:my_decorator:my_method:('test', 123) {'name': 'foo'}")
self.assertEqual(obj.my_method.__name__, 'my_method')
self.assertEqual(getattr(obj.my_method, 'my_decorator_custom_attribute', False),
True)
self.assertEqual(getattr(obj.my_method, 'my_decorator2_custom_attribute', False),
True)