Django 的 urls 文件解释两次
Django's urls file interpretes twice
我在我的 Django 项目中发现了一个非常奇怪的行为。我的 urls.py 由于某种原因被解释了两次，不幸的是这造成了很多麻烦。为了调试，我把这两行
import traceback
tracebak.print_stack()
进入我的 urls.py 文件。这是我执行 ./manage.py runserver:
时得到的输出
File "/usr/lib/python3.7/threading.py", line 890, in _bootstrap
self._bootstrap_inner()
File "/usr/lib/python3.7/threading.py", line 926, in _bootstrap_inner
self.run()
File "/usr/lib/python3.7/threading.py", line 870, in run
self._target(*self._args, **self._kwargs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/autoreload.py", line 54, in wrapper
fn(*args, **kwargs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py", line 117, in inner_run
self.check(display_num_errors=True)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/base.py", line 390, in check
include_deployment_checks=include_deployment_checks,
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/base.py", line 377, in _run_checks
return checks.run_checks(**kwargs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/checks/registry.py", line 72, in run_checks
new_errors = check(app_configs=app_configs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/checks/urls.py", line 13, in check_url_config
return check_resolver(resolver)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/checks/urls.py", line 23, in check_resolver
return check_method()
File "/home/user/project/venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 398, in check
for pattern in self.url_patterns:
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/functional.py", line 80, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/home/user/project/venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 579, in url_patterns
patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/functional.py", line 80, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/home/user/project/venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 572, in urlconf_module
return import_module(self.urlconf_name)
File "/usr/lib/python3.7/importlib/__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
File "<frozen importlib._bootstrap>", line 983, in _find_and_load
File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 728, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "/home/user/project/urls.py", line 23, in <module>
traceback.print_stack()
和另一个堆栈：
File "/home/user/project/manage.py", line 21, in <module>
main()
File "/home/user/project/manage.py", line 17, in main
execute_from_command_line(sys.argv)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
utility.execute()
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/__init__.py", line 375, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/base.py", line 323, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py", line 60, in execute
super().execute(*args, **options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/base.py", line 364, in execute
output = self.handle(*args, **options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py", line 95, in handle
self.run(**options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py", line 102, in run
autoreload.run_with_reloader(self.inner_run, **options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/autoreload.py", line 598, in run_with_reloader
start_django(reloader, main_func, *args, **kwargs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/autoreload.py", line 583, in start_django
reloader.run(django_main_thread)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/autoreload.py", line 294, in run
get_resolver().urlconf_module
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/functional.py", line 80, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/home/user/project/venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 572, in urlconf_module
return import_module(self.urlconf_name)
File "/usr/lib/python3.7/importlib/__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
File "<frozen importlib._bootstrap>", line 983, in _find_and_load
File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 728, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "/home/user/project/urls.py", line 23, in <module>
traceback.print_stack()
有什么可能导致此行为的想法吗？例如，它可能是我项目中某处的一些导入吗？我完全不知道我应该包括哪些代码，所以如果你有想法，请告诉我，我会添加它们。
当您 运行 您的 Django 应用程序使用开发服务器时，会生成一个自动重新加载程序进程来检测代码中的更改。此进程的初始化方式与您的主服务器进程相同，这可能是您的 urls.py 文件被执行两次的原因。
要验证这是否是您的问题的原因，您可以尝试 运行 没有自动重新加载选项的开发服务器：
python manage.py runserver --noreload
我在我的 Django 项目中发现了一个非常奇怪的行为。我的 urls.py 由于某种原因被解释了两次，不幸的是这造成了很多麻烦。为了调试，我把这两行
import traceback
tracebak.print_stack()
进入我的 urls.py 文件。这是我执行 ./manage.py runserver:
File "/usr/lib/python3.7/threading.py", line 890, in _bootstrap
self._bootstrap_inner()
File "/usr/lib/python3.7/threading.py", line 926, in _bootstrap_inner
self.run()
File "/usr/lib/python3.7/threading.py", line 870, in run
self._target(*self._args, **self._kwargs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/autoreload.py", line 54, in wrapper
fn(*args, **kwargs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py", line 117, in inner_run
self.check(display_num_errors=True)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/base.py", line 390, in check
include_deployment_checks=include_deployment_checks,
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/base.py", line 377, in _run_checks
return checks.run_checks(**kwargs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/checks/registry.py", line 72, in run_checks
new_errors = check(app_configs=app_configs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/checks/urls.py", line 13, in check_url_config
return check_resolver(resolver)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/checks/urls.py", line 23, in check_resolver
return check_method()
File "/home/user/project/venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 398, in check
for pattern in self.url_patterns:
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/functional.py", line 80, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/home/user/project/venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 579, in url_patterns
patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/functional.py", line 80, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/home/user/project/venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 572, in urlconf_module
return import_module(self.urlconf_name)
File "/usr/lib/python3.7/importlib/__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
File "<frozen importlib._bootstrap>", line 983, in _find_and_load
File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 728, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "/home/user/project/urls.py", line 23, in <module>
traceback.print_stack()
和另一个堆栈：
File "/home/user/project/manage.py", line 21, in <module>
main()
File "/home/user/project/manage.py", line 17, in main
execute_from_command_line(sys.argv)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
utility.execute()
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/__init__.py", line 375, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/base.py", line 323, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py", line 60, in execute
super().execute(*args, **options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/base.py", line 364, in execute
output = self.handle(*args, **options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py", line 95, in handle
self.run(**options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py", line 102, in run
autoreload.run_with_reloader(self.inner_run, **options)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/autoreload.py", line 598, in run_with_reloader
start_django(reloader, main_func, *args, **kwargs)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/autoreload.py", line 583, in start_django
reloader.run(django_main_thread)
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/autoreload.py", line 294, in run
get_resolver().urlconf_module
File "/home/user/project/venv/lib/python3.7/site-packages/django/utils/functional.py", line 80, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/home/user/project/venv/lib/python3.7/site-packages/django/urls/resolvers.py", line 572, in urlconf_module
return import_module(self.urlconf_name)
File "/usr/lib/python3.7/importlib/__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
File "<frozen importlib._bootstrap>", line 983, in _find_and_load
File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 728, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "/home/user/project/urls.py", line 23, in <module>
traceback.print_stack()
有什么可能导致此行为的想法吗？例如，它可能是我项目中某处的一些导入吗？我完全不知道我应该包括哪些代码，所以如果你有想法，请告诉我，我会添加它们。
当您 运行 您的 Django 应用程序使用开发服务器时，会生成一个自动重新加载程序进程来检测代码中的更改。此进程的初始化方式与您的主服务器进程相同，这可能是您的 urls.py 文件被执行两次的原因。
要验证这是否是您的问题的原因，您可以尝试 运行 没有自动重新加载选项的开发服务器：
python manage.py runserver --noreload