Refs #31949 -- Made @sensitive_variables/sensitive_post_parameters decorators to work with async functions.

Co-authored-by: Mariusz Felisiak <felisiak.mariusz@gmail.com>

django/views/debug.py

@@ -1,4 +1,5 @@
 import functools
+import inspect
 import itertools
 import re
 import sys
@@ -17,6 +18,7 @@ from django.utils.encoding import force_str
 from django.utils.module_loading import import_string
 from django.utils.regex_helper import _lazy_re_compile
 from django.utils.version import PY311, get_docs_version
+from django.views.decorators.debug import coroutine_functions_to_sensitive_variables
 
 # Minimal Django templates engine to render the error templates
 # regardless of the project's TEMPLATES setting. Templates are
@@ -239,21 +241,37 @@ class SafeExceptionReporterFilter:
         Replace the values of variables marked as sensitive with
         stars (*********).
         """
-        # Loop through the frame's callers to see if the sensitive_variables
-        # decorator was used.
-        current_frame = tb_frame.f_back
         sensitive_variables = None
-        while current_frame is not None:
-            if (
-                current_frame.f_code.co_name == "sensitive_variables_wrapper"
-                and "sensitive_variables_wrapper" in current_frame.f_locals
-            ):
-                # The sensitive_variables decorator was used, so we take note
-                # of the sensitive variables' names.
-                wrapper = current_frame.f_locals["sensitive_variables_wrapper"]
-                sensitive_variables = getattr(wrapper, "sensitive_variables", None)
-                break
-            current_frame = current_frame.f_back
+
+        # Coroutines don't have a proper `f_back` so they need to be inspected
+        # separately. Handle this by stashing the registered sensitive
+        # variables in a global dict indexed by `hash(file_path:line_number)`.
+        if (
+            tb_frame.f_code.co_flags & inspect.CO_COROUTINE != 0
+            and tb_frame.f_code.co_name != "sensitive_variables_wrapper"
+        ):
+            key = hash(
+                f"{tb_frame.f_code.co_filename}:{tb_frame.f_code.co_firstlineno}"
+            )
+            sensitive_variables = coroutine_functions_to_sensitive_variables.get(
+                key, None
+            )
+
+        if sensitive_variables is None:
+            # Loop through the frame's callers to see if the
+            # sensitive_variables decorator was used.
+            current_frame = tb_frame
+            while current_frame is not None:
+                if (
+                    current_frame.f_code.co_name == "sensitive_variables_wrapper"
+                    and "sensitive_variables_wrapper" in current_frame.f_locals
+                ):
+                    # The sensitive_variables decorator was used, so take note
+                    # of the sensitive variables' names.
+                    wrapper = current_frame.f_locals["sensitive_variables_wrapper"]
+                    sensitive_variables = getattr(wrapper, "sensitive_variables", None)
+                    break
+                current_frame = current_frame.f_back
 
         cleansed = {}
         if self.is_active(request) and sensitive_variables:

django/views/decorators/debug.py

@@ -1,7 +1,12 @@
+import inspect
 from functools import wraps
 
+from asgiref.sync import iscoroutinefunction
+
 from django.http import HttpRequest
 
+coroutine_functions_to_sensitive_variables = {}
+
 
 def sensitive_variables(*variables):
     """
@@ -33,13 +38,42 @@ def sensitive_variables(*variables):
         )
 
     def decorator(func):
-        @wraps(func)
-        def sensitive_variables_wrapper(*func_args, **func_kwargs):
+        if iscoroutinefunction(func):
+
+            @wraps(func)
+            async def sensitive_variables_wrapper(*func_args, **func_kwargs):
+                return await func(*func_args, **func_kwargs)
+
+            wrapped_func = func
+            while getattr(wrapped_func, "__wrapped__", None) is not None:
+                wrapped_func = wrapped_func.__wrapped__
+
+            try:
+                file_path = inspect.getfile(wrapped_func)
+                _, first_file_line = inspect.getsourcelines(wrapped_func)
+            except TypeError:  # Raises for builtins or native functions.
+                raise ValueError(
+                    f"{func.__name__} cannot safely be wrapped by "
+                    "@sensitive_variables, make it either non-async or defined in a "
+                    "Python file (not a builtin or from a native extension)."
+                )
+            else:
+                key = hash(f"{file_path}:{first_file_line}")
+
             if variables:
-                sensitive_variables_wrapper.sensitive_variables = variables
+                coroutine_functions_to_sensitive_variables[key] = variables
             else:
-                sensitive_variables_wrapper.sensitive_variables = "__ALL__"
-            return func(*func_args, **func_kwargs)
+                coroutine_functions_to_sensitive_variables[key] = "__ALL__"
+
+        else:
+
+            @wraps(func)
+            def sensitive_variables_wrapper(*func_args, **func_kwargs):
+                if variables:
+                    sensitive_variables_wrapper.sensitive_variables = variables
+                else:
+                    sensitive_variables_wrapper.sensitive_variables = "__ALL__"
+                return func(*func_args, **func_kwargs)
 
         return sensitive_variables_wrapper
 
@@ -77,19 +111,37 @@ def sensitive_post_parameters(*parameters):
         )
 
     def decorator(view):
-        @wraps(view)
-        def sensitive_post_parameters_wrapper(request, *args, **kwargs):
-            if not isinstance(request, HttpRequest):
-                raise TypeError(
-                    "sensitive_post_parameters didn't receive an HttpRequest "
-                    "object. If you are decorating a classmethod, make sure "
-                    "to use @method_decorator."
-                )
-            if parameters:
-                request.sensitive_post_parameters = parameters
-            else:
-                request.sensitive_post_parameters = "__ALL__"
-            return view(request, *args, **kwargs)
+        if iscoroutinefunction(view):
+
+            @wraps(view)
+            async def sensitive_post_parameters_wrapper(request, *args, **kwargs):
+                if not isinstance(request, HttpRequest):
+                    raise TypeError(
+                        "sensitive_post_parameters didn't receive an HttpRequest "
+                        "object. If you are decorating a classmethod, make sure to use "
+                        "@method_decorator."
+                    )
+                if parameters:
+                    request.sensitive_post_parameters = parameters
+                else:
+                    request.sensitive_post_parameters = "__ALL__"
+                return await view(request, *args, **kwargs)
+
+        else:
+
+            @wraps(view)
+            def sensitive_post_parameters_wrapper(request, *args, **kwargs):
+                if not isinstance(request, HttpRequest):
+                    raise TypeError(
+                        "sensitive_post_parameters didn't receive an HttpRequest "
+                        "object. If you are decorating a classmethod, make sure to use "
+                        "@method_decorator."
+                    )
+                if parameters:
+                    request.sensitive_post_parameters = parameters
+                else:
+                    request.sensitive_post_parameters = "__ALL__"
+                return view(request, *args, **kwargs)
 
         return sensitive_post_parameters_wrapper
 

docs/howto/error-reporting.txt

@@ -205,6 +205,10 @@ filtered out of error reports in a production environment (that is, where
         exception reporting, and consider implementing a :ref:`custom filter
         <custom-error-reports>` if necessary.
 
+    .. versionchanged:: 5.0
+
+        Support for wrapping ``async`` functions was added.
+
 .. function:: sensitive_post_parameters(*parameters)
 
     If one of your views receives an :class:`~django.http.HttpRequest` object
@@ -245,6 +249,10 @@ filtered out of error reports in a production environment (that is, where
     ``user_change_password`` in the ``auth`` admin) to prevent the leaking of
     sensitive information such as user passwords.
 
+    .. versionchanged:: 5.0
+
+        Support for wrapping ``async`` functions was added.
+
 .. _custom-error-reports:
 
 Custom error reports

docs/releases/5.0.txt

@@ -241,6 +241,8 @@ Decorators
   * :func:`~django.views.decorators.cache.cache_control`
   * :func:`~django.views.decorators.cache.never_cache`
   * :func:`~django.views.decorators.common.no_append_slash`
+  * :func:`~django.views.decorators.debug.sensitive_variables`
+  * :func:`~django.views.decorators.debug.sensitive_post_parameters`
   * ``xframe_options_deny()``
   * ``xframe_options_sameorigin()``
   * ``xframe_options_exempt()``
@@ -253,7 +255,9 @@ Email
 Error Reporting
 ~~~~~~~~~~~~~~~
 
-* ...
+* :func:`~django.views.decorators.debug.sensitive_variables` and
+  :func:`~django.views.decorators.debug.sensitive_post_parameters` can now be
+  used with asynchronous functions.
 
 File Storage
 ~~~~~~~~~~~~

tests/view_tests/tests/test_debug.py

@@ -9,6 +9,8 @@ from io import StringIO
 from pathlib import Path
 from unittest import mock, skipIf, skipUnless
 
+from asgiref.sync import async_to_sync, iscoroutinefunction
+
 from django.core import mail
 from django.core.files.uploadedfile import SimpleUploadedFile
 from django.db import DatabaseError, connection
@@ -39,6 +41,10 @@ from django.views.debug import (
 from django.views.decorators.debug import sensitive_post_parameters, sensitive_variables
 
 from ..views import (
+    async_sensitive_method_view,
+    async_sensitive_method_view_nested,
+    async_sensitive_view,
+    async_sensitive_view_nested,
     custom_exception_reporter_filter_view,
     index_page,
     multivalue_dict_key_error,
@@ -1351,7 +1357,10 @@ class ExceptionReportTestMixin:
         Asserts that potentially sensitive info are displayed in the response.
         """
         request = self.rf.post("/some_url/", self.breakfast_data)
-        response = view(request)
+        if iscoroutinefunction(view):
+            response = async_to_sync(view)(request)
+        else:
+            response = view(request)
         if check_for_vars:
             # All variables are shown.
             self.assertContains(response, "cooked_eggs", status_code=500)
@@ -1371,7 +1380,10 @@ class ExceptionReportTestMixin:
         Asserts that certain sensitive info are not displayed in the response.
         """
         request = self.rf.post("/some_url/", self.breakfast_data)
-        response = view(request)
+        if iscoroutinefunction(view):
+            response = async_to_sync(view)(request)
+        else:
+            response = view(request)
         if check_for_vars:
             # Non-sensitive variable's name and value are shown.
             self.assertContains(response, "cooked_eggs", status_code=500)
@@ -1418,7 +1430,10 @@ class ExceptionReportTestMixin:
         with self.settings(ADMINS=[("Admin", "admin@fattie-breakie.com")]):
             mail.outbox = []  # Empty outbox
             request = self.rf.post("/some_url/", self.breakfast_data)
-            view(request)
+            if iscoroutinefunction(view):
+                async_to_sync(view)(request)
+            else:
+                view(request)
             self.assertEqual(len(mail.outbox), 1)
             email = mail.outbox[0]
 
@@ -1451,7 +1466,10 @@ class ExceptionReportTestMixin:
         with self.settings(ADMINS=[("Admin", "admin@fattie-breakie.com")]):
             mail.outbox = []  # Empty outbox
             request = self.rf.post("/some_url/", self.breakfast_data)
-            view(request)
+            if iscoroutinefunction(view):
+                async_to_sync(view)(request)
+            else:
+                view(request)
             self.assertEqual(len(mail.outbox), 1)
             email = mail.outbox[0]
 
@@ -1543,6 +1561,24 @@ class ExceptionReporterFilterTests(
             self.verify_safe_response(sensitive_view)
             self.verify_safe_email(sensitive_view)
 
+    def test_async_sensitive_request(self):
+        with self.settings(DEBUG=True):
+            self.verify_unsafe_response(async_sensitive_view)
+            self.verify_unsafe_email(async_sensitive_view)
+
+        with self.settings(DEBUG=False):
+            self.verify_safe_response(async_sensitive_view)
+            self.verify_safe_email(async_sensitive_view)
+
+    def test_async_sensitive_nested_request(self):
+        with self.settings(DEBUG=True):
+            self.verify_unsafe_response(async_sensitive_view_nested)
+            self.verify_unsafe_email(async_sensitive_view_nested)
+
+        with self.settings(DEBUG=False):
+            self.verify_safe_response(async_sensitive_view_nested)
+            self.verify_safe_email(async_sensitive_view_nested)
+
     def test_paranoid_request(self):
         """
         No POST parameters and frame variables can be seen in the
@@ -1598,6 +1634,46 @@ class ExceptionReporterFilterTests(
             )
             self.verify_safe_email(sensitive_method_view, check_for_POST_params=False)
 
+    def test_async_sensitive_method(self):
+        """
+        The sensitive_variables decorator works with async object methods.
+        """
+        with self.settings(DEBUG=True):
+            self.verify_unsafe_response(
+                async_sensitive_method_view, check_for_POST_params=False
+            )
+            self.verify_unsafe_email(
+                async_sensitive_method_view, check_for_POST_params=False
+            )
+
+        with self.settings(DEBUG=False):
+            self.verify_safe_response(
+                async_sensitive_method_view, check_for_POST_params=False
+            )
+            self.verify_safe_email(
+                async_sensitive_method_view, check_for_POST_params=False
+            )
+
+    def test_async_sensitive_method_nested(self):
+        """
+        The sensitive_variables decorator works with async object methods.
+        """
+        with self.settings(DEBUG=True):
+            self.verify_unsafe_response(
+                async_sensitive_method_view_nested, check_for_POST_params=False
+            )
+            self.verify_unsafe_email(
+                async_sensitive_method_view_nested, check_for_POST_params=False
+            )
+
+        with self.settings(DEBUG=False):
+            self.verify_safe_response(
+                async_sensitive_method_view_nested, check_for_POST_params=False
+            )
+            self.verify_safe_email(
+                async_sensitive_method_view_nested, check_for_POST_params=False
+            )
+
     def test_sensitive_function_arguments(self):
         """
         Sensitive variables don't leak in the sensitive_variables decorator's
@@ -1890,6 +1966,30 @@ class NonHTMLResponseExceptionReporterFilter(
         with self.settings(DEBUG=False):
             self.verify_safe_response(sensitive_view, check_for_vars=False)
 
+    def test_async_sensitive_request(self):
+        """
+        Sensitive POST parameters cannot be seen in the default
+        error reports for sensitive requests.
+        """
+        with self.settings(DEBUG=True):
+            self.verify_unsafe_response(async_sensitive_view, check_for_vars=False)
+
+        with self.settings(DEBUG=False):
+            self.verify_safe_response(async_sensitive_view, check_for_vars=False)
+
+    def test_async_sensitive_request_nested(self):
+        """
+        Sensitive POST parameters cannot be seen in the default
+        error reports for sensitive requests.
+        """
+        with self.settings(DEBUG=True):
+            self.verify_unsafe_response(
+                async_sensitive_view_nested, check_for_vars=False
+            )
+
+        with self.settings(DEBUG=False):
+            self.verify_safe_response(async_sensitive_view_nested, check_for_vars=False)
+
     def test_paranoid_request(self):
         """
         No POST parameters can be seen in the default error reports

tests/view_tests/views.py

@@ -178,6 +178,46 @@ def sensitive_view(request):
         return technical_500_response(request, *exc_info)
 
 
+@sensitive_variables("sauce")
+@sensitive_post_parameters("bacon-key", "sausage-key")
+async def async_sensitive_view(request):
+    # Do not just use plain strings for the variables' values in the code so
+    # that the tests don't return false positives when the function's source is
+    # displayed in the exception report.
+    cooked_eggs = "".join(["s", "c", "r", "a", "m", "b", "l", "e", "d"])  # NOQA
+    sauce = "".join(  # NOQA
+        ["w", "o", "r", "c", "e", "s", "t", "e", "r", "s", "h", "i", "r", "e"]
+    )
+    try:
+        raise Exception
+    except Exception:
+        exc_info = sys.exc_info()
+        send_log(request, exc_info)
+        return technical_500_response(request, *exc_info)
+
+
+@sensitive_variables("sauce")
+@sensitive_post_parameters("bacon-key", "sausage-key")
+async def async_sensitive_function(request):
+    # Do not just use plain strings for the variables' values in the code so
+    # that the tests don't return false positives when the function's source is
+    # displayed in the exception report.
+    cooked_eggs = "".join(["s", "c", "r", "a", "m", "b", "l", "e", "d"])  # NOQA
+    sauce = "".join(  # NOQA
+        ["w", "o", "r", "c", "e", "s", "t", "e", "r", "s", "h", "i", "r", "e"]
+    )
+    raise Exception
+
+
+async def async_sensitive_view_nested(request):
+    try:
+        await async_sensitive_function(request)
+    except Exception:
+        exc_info = sys.exc_info()
+        send_log(request, exc_info)
+        return technical_500_response(request, *exc_info)
+
+
 @sensitive_variables()
 @sensitive_post_parameters()
 def paranoid_view(request):
@@ -309,11 +349,54 @@ class Klass:
             send_log(request, exc_info)
             return technical_500_response(request, *exc_info)
 
+    @sensitive_variables("sauce")
+    async def async_method(self, request):
+        # Do not just use plain strings for the variables' values in the code
+        # so that the tests don't return false positives when the function's
+        # source is displayed in the exception report.
+        cooked_eggs = "".join(["s", "c", "r", "a", "m", "b", "l", "e", "d"])  # NOQA
+        sauce = "".join(  # NOQA
+            ["w", "o", "r", "c", "e", "s", "t", "e", "r", "s", "h", "i", "r", "e"]
+        )
+        try:
+            raise Exception
+        except Exception:
+            exc_info = sys.exc_info()
+            send_log(request, exc_info)
+            return technical_500_response(request, *exc_info)
+
+    @sensitive_variables("sauce")
+    async def _async_method_inner(self, request):
+        # Do not just use plain strings for the variables' values in the code
+        # so that the tests don't return false positives when the function's
+        # source is displayed in the exception report.
+        cooked_eggs = "".join(["s", "c", "r", "a", "m", "b", "l", "e", "d"])  # NOQA
+        sauce = "".join(  # NOQA
+            ["w", "o", "r", "c", "e", "s", "t", "e", "r", "s", "h", "i", "r", "e"]
+        )
+        raise Exception
+
+    async def async_method_nested(self, request):
+        try:
+            await self._async_method_inner(request)
+        except Exception:
+            exc_info = sys.exc_info()
+            send_log(request, exc_info)
+            return technical_500_response(request, *exc_info)
+
 
 def sensitive_method_view(request):
     return Klass().method(request)
 
 
+async def async_sensitive_method_view(request):
+    return await Klass().async_method(request)
+
+
+async def async_sensitive_method_view_nested(request):
+    return await Klass().async_method_nested(request)
+
+
 @sensitive_variables("sauce")
 @sensitive_post_parameters("bacon-key", "sausage-key")
 def multivalue_dict_key_error(request):