Using Assignment and Grades throws an error on Dark language middleware

[Alain1405]

Release: Maple
Relevant settings: ENABLE_COMPREHENSIVE_THEMING=True
LTI consumer settings:

• LTI version: 1.3
• Enable LTI NRPS: True
• Deep linking: True
• LTI Assignment and Grades Service: Programmatic
• Everything else: True

We have configured an LTI 1.3 producer using PyLTI1p3 library (using the Django example).

The connection works fine, however when the tool uses the Assignment and Grades service or Names and Roles service, every time it sends a requests to our Maple instance, it triggers a 500 due to missing user at https://github.com/edx/edx-platform/blob/4f49475b94a61c3290c1813f5272277b7986b06c/openedx/core/djangoapps/dark_lang/middleware.py#L159

The error is:

AttributeError
'NoneType' object has no attribute 'is_authenticated'
openedx/core/djangoapps/dark_lang/middleware.py in _activate_preview_language at line 165
openedx/core/djangoapps/dark_lang/middleware.py in process_response at line 102
django/utils/deprecation.py in __call__ at line 119
django/core/handlers/exception.py in inner at line 47

[Alain1405]

@giovannicimolin we are also facing this issue #217

[Alain1405]

I have done more investigation.

• The LTI tool is sending a POST to submit a grade to edxplatform.com/api/lti_consumer/v1/lti/4/lti-ags
• The ViewSet LtiAgsLineItemViewset processes the request

  xblock-lti-consumer/lti_consumer/plugin/views.py

  Line 305 in 582597a

  class LtiAgsLineItemViewset(viewsets.ModelViewSet):

• As part of the authentication process, Lti1p3ApiAuthentication is called. In there, I found the note This doesn't return a user, but let's the external access and commit changes. TODO: Consider creating an user for LTI operations, both to keep track of changes and to use Django's authorization flow.

  xblock-lti-consumer/lti_consumer/lti_1p3/extensions/rest_framework/authentication.py

  Line 32 in 582597a

  TODO: Consider creating an user for LTI operations, both to keep track

• Somewhere before a response is returned or even before the score is stored, edx tries to render a template but given that no Django user is in the request the rendering fail

Full error log below:

Jan 12 09:35:50 ip-10-121-9-198 [service_variant=lms][root][env:sandbox] ERROR [ip-10-121-9-198  19004] [user None] [ip 35.76.151.108] [signals.py:22] - Uncaught exception from None
Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 119, in __call__
    response = self.process_response(request, response)
  File "/edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py", line 102, in process_response
    self._activate_preview_language(request, response)
  File "/edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py", line 165, in _activate_preview_language
    auth_user = request.user.is_authenticated
AttributeError: 'NoneType' object has no attribute 'is_authenticated'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 244, in bind_template
    updates.update(processor(self.request))
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/courseware/context_processor.py", line 40, in user_timezone_locale_prefs
    if hasattr(request, 'user') and request.user.is_authenticated:
AttributeError: 'NoneType' object has no attribute 'is_authenticated'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 114, in response_for_exception
    response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 153, in handle_uncaught_exception
    return callback(request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/util/views.py", line 95, in wrapper
    return func(request, *args, **kwargs)
  File "/edx/app/edxapp/edx-platform/lms/djangoapps/static_template_view/views.py", line 125, in render_500
    return HttpResponseServerError(render_to_string('static_templates/server-error.html', {}, request=request))
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/shortcuts.py", line 178, in render_to_string
    return template.render(dictionary, request)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 66, in render
    context_dictionary = self._get_context_processors_output_dict(context_object)
  File "/edx/app/edxapp/edx-platform/common/djangoapps/edxmako/template.py", line 100, in _get_context_processors_output_dict
    with context_object.bind_template(self):
  File "/usr/lib/python3.8/contextlib.py", line 113, in __enter__
    return next(self.gen)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/template/context.py", line 236, in bind_template
    raise RuntimeError("Context is already bound to a template")
RuntimeError: Context is already bound to a template

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/sentry_sdk/integrations/django/middleware.py", line 175, in __call__
    return f(*args, **kwargs)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 117, in __call__
    response = response or self.get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 49, in inner
    response = response_for_exception(request, exc)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/co

[Alain1405]

Additionally, maybe related, DeepLinking seems to work until after changing the configurations on the tool we return to edx, where we get the following message with a 403:

You don't have access to save LTI Content Items.

Please check that you have course staff permissions and double check this block's LTI settings.

Request URL: POST platform.url/api/lti_consumer/v1/lti/4/lti-dl/response

The response is triggered at

xblock-lti-consumer/lti_consumer/plugin/views.py

Line 249 in 582597a

except (Lti1p3Exception, PermissionDenied) as exc:

potentially because the request doesn't have the right user data for user_has_staff_access to succeed

xblock-lti-consumer/lti_consumer/plugin/views.py

Line 195 in 582597a

if not user_has_staff_access(request.user, course_key):

The weird part is that when we get redirect back to edx the user (superuser) gets logged out.

[giovannicimolin]

@Alain1405 I'm pretty sure I've bumped into this problem before.
Can you check if the cookies from you Open edX instance have SameSite=None?
If not, the cookies won't be sent when the page is redirected and the LMS will think it's an Unauthenticated request.

Let me do some testing on my end.

---

Edit:
Can you try setting DCS_SESSION_COOKIE_SAMESITE = 'None' and trying to run the launches again?
LTI launches, LTI-AGS and Deep Linking seem to be working properly for me.

Also, what's the permission level of your user? Is he superuser or just staff?

[Alain1405]

@giovannicimolin

Also, what's the permission level of your user? Is he superuser or just staff?

is a superuser.

LTI launches, LTI-AGS and Deep Linking seem to be working properly for me.

Do you have comprehensive theming enabled?

Can you try setting DCS_SESSION_COOKIE_SAMESITE = 'None' and trying to run the launches again?

We will try and get back to you

[OlhaShyliaieva]

@giovannicimolin I tried setting DCS_SESSION_COOKIE_SAMESITE = 'None' and it doesn’t help.
I guess that the main problem is the Lti1p3ApiAuthentication authentication class of LtiAgsLineItemViewset which always sets user in request as None. DarkLangMiddleware at the edx-platform handles every response and tries to get a user from a request in a not intelligent way.

I think that this issue can be resolved in several ways.
The first one is to implement user authentication which was discussed at #105 (review).

Another quick decision is to change user which Lti1p3ApiAuthentication returns from None to AnonymousUser().
The last one is to make _activate_preview_language at DarkLangMiddleware more clever and handle a user by way like this https://github.com/openedx/edx-platform/blob/open-release/maple.1/common/djangoapps/xblock_django/user_service.py#L77

For example:

def _activate_preview_language(self, request, response):
        """
        Check the user's dark language setting in the session and apply it
        """
        auth_user = request.user and request.user.is_authenticated
        preview_lang = None
        if auth_user:
            ....

[giovannicimolin]

@Alain1405 @Alain1405 I hear you on the user issue, and I agree with your suggestions, but there might be a underlying problem we're not seeing that is surfacing this error.

The LTI-AGS endpoints are purely for server-to-server communication and should never try to load a template, so I'm wondering why the DarkLang middleware is kicking in.

• Are you actively using the DarkLang middleware on your instances? (is your site multi-language?)
• Can you debug the request coming in your platform (by adding a breakpoint and pasting request data here)? I'd like to check if the request itself is triggering some code that shouldn't be triggered.

[Alain1405]

Are you actively using the DarkLang middleware on your instances? (is your site multi-language?)

Yes we do.

Can you debug the request coming in your platform (by adding a breakpoint and pasting request data here)? I'd like to check if the request itself is triggering some code that shouldn't be triggered.

We'll send soon.

[OlhaShyliaieva]

@giovannicimolin I set the breakpoint in _activate_preview_language method at DarkLangMiddleware. Here is the traceback please take a look and let me know if you need more information.

> /edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py(167)_activate_preview_language()
-> auth_user = request.user.is_authenticated
(Pdb) request
<WSGIRequest: GET '/api/lti_consumer/v1/lti/3/lti-ags'>
(Pdb) request.headers
{'Content-Length': '', 'Content-Type': 'text/plain', 'Host': '88b4-91-193-174-13.ngrok.io', 'User-Agent': 'python-requests/2.27.1', 'Accept': 'application/vnd.ims.lis.v2.lineitemcontainer+json', 'Accept-Encoding': 'gzip, deflate', 'Authorization': 'Bearer eyJhbGciOiJSUzI1NiIsImtpZCI6ImQ2ODkwZTllLWE3NDAtNDFlOC05MjBlLWVlMDMzYjYyNWQ2NSJ9.eyJzdWIiOiJhYTNjNjFkMi0xNjdmLTRkN2MtOWYzMS03ZWU3N2JjYjk4MDMiLCJpc3MiOiJodHRwOi8vODhiNC05MS0xOTMtMTc0LTEzLm5ncm9rLmlvIiwic2NvcGVzIjoiaHR0cHM6Ly9wdXJsLmltc2dsb2JhbC5vcmcvc3BlYy9sdGktYWdzL3Njb3BlL2xpbmVpdGVtIGh0dHBzOi8vcHVybC5pbXNnbG9iYWwub3JnL3NwZWMvbHRpLWFncy9zY29wZS9yZXN1bHQucmVhZG9ubHkgaHR0cHM6Ly9wdXJsLmltc2dsb2JhbC5vcmcvc3BlYy9sdGktYWdzL3Njb3BlL3Njb3JlIiwiaWF0IjoxNjQzNjQ2NDMzLCJleHAiOjE2NDM2NTAwMzN9.qimmDWo-DX4ptvo09U2hKhM16y2ycdlvI-UyUgXyDE1AdDRLc4hnGyn414VnqfJcYv0LqEB-DcFTDsscF-llown9l2F44-KM14xKhQlOaR6q7JNQ2XPt2LV8W_qmaxqniKmxf_KO13atlXPPRntsYX_TfPDCoT7uwPdKHecz6nasjf9a_8ISxA9F6Dp3Zv85hRmhbCNfpUn2_lMYRmAikbdbkmaCXmovmvr_XVHQzzKQoVs_MSpcY2Z8VJoYTKMJJXhbBQr9nqr1X5IJcataWuEHIDB90VZyVKacyHFHPOGTCDew3SwDuBkhquMr818lS26aqVs-5MKcZgTQxPbapA', 'X-Forwarded-For': '91.193.174.13', 'X-Forwarded-Proto': 'http'}
(Pdb) request.path_info
'/api/lti_consumer/v1/lti/3/lti-ags'
(Pdb) request.view_name
'LtiAgsLineItemViewset'
(Pdb) request.method
'GET'
(Pdb) request.content_type
'text/plain'
(Pdb) request.user
(Pdb) print(request.user)
None
(Pdb) request.auth
(Pdb) print(request.auth)
None
(Pdb) request.accepted_types
[<MediaType: application/vnd.ims.lis.v2.lineitemcontainer+json>]
(Pdb) next
AttributeError: 'NoneType' object has no attribute 'is_authenticated'
> /edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py(167)_activate_preview_language()
-> auth_user = request.user.is_authenticated
(Pdb) continue
2022-01-31 16:35:00,518 ERROR 2154 [root] [user None] [ip 91.193.174.13] signals.py:22 - Uncaught exception from None
Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 119, in __call__
    response = self.process_response(request, response)
  File "/edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py", line 102, in process_response
    self._activate_preview_language(request, response)
  File "/edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py", line 167, in _activate_preview_language
    auth_user = request.user.is_authenticated
AttributeError: 'NoneType' object has no attribute 'is_authenticated'
Internal Server Error: /api/lti_consumer/v1/lti/3/lti-ags
Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 119, in __call__
    response = self.process_response(request, response)
  File "/edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py", line 102, in process_response
    self._activate_preview_language(request, response)
  File "/edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py", line 167, in _activate_preview_language
    auth_user = request.user.is_authenticated
AttributeError: 'NoneType' object has no attribute 'is_authenticated'
2022-01-31 16:35:00,562 ERROR 2154 [django.request] [user None] [ip 91.193.174.13] log.py:224 - Internal Server Error: /api/lti_consumer/v1/lti/3/lti-ags
Traceback (most recent call last):
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/edx/app/edxapp/venvs/edxapp/lib/python3.8/site-packages/django/utils/deprecation.py", line 119, in __call__
    response = self.process_response(request, response)
  File "/edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py", line 102, in process_response
    self._activate_preview_language(request, response)
  File "/edx/app/edxapp/edx-platform/openedx/core/djangoapps/dark_lang/middleware.py", line 167, in _activate_preview_language
    auth_user = request.user.is_authenticated
AttributeError: 'NoneType' object has no attribute 'is_authenticated'
[31/Jan/2022 16:35:00] "GET /api/lti_consumer/v1/lti/3/lti-ags HTTP/1.1" 500 129768 

[regisb]

Here is an example of a request that triggers the error:

ipdb> pp(request.__dict__)                                                                                                                                                                                         
{
    'COOKIES': {},                                                                                                                                                                                                    
    'GET': <QueryDict: {}>,                                                                                                                                                                                           
    'LANGUAGE_CODE': 'en',                                                                                                                                                                                            
    'META': {
        'CONTENT_LENGTH': '',                                                                                                                                                                                    
        'CONTENT_TYPE': 'text/plain',                                                                                                                                                                            
        'DEBIAN_FRONTEND': 'noninteractive',                                                                                                                                                                     
        'DJANGO_SETTINGS_MODULE': 'lms.envs.tutor.development',                                                                                                                                                  
        'GATEWAY_INTERFACE': 'CGI/1.1',                                                                                                                                                                          
        'HOME': '/openedx',                                                                                                                                                                                      
        'HOSTNAME': '678e52b7e5e1',                                                                                                                                                                              
        'HTTP_ACCEPT': 'application/vnd.ims.lis.v2.lineitemcontainer+json',                                                                                                                                      
        'HTTP_ACCEPT_ENCODING': 'gzip, deflate',                                                                                                                                                                 
        'HTTP_AUTHORIZATION': 'Bearer '                                                                                                                                                                          
                                'eyJhbGciOiJSUzI1NiIsImtpZCI6ImViN2MyYTJmLTExMzYtNGNiNi1iNGJhLTJiZjc5ZjA5M2Q0NCJ9.eyJzdWIiOiJmOTdjMmM3ZS0yZDUxLTRhM2YtYTUyMC05NzE4ZmJhN2U3ZDQiLCJpc3MiOiJodHRwOi8vbG9jYWwub3Zlcmhhb
mcuaW86ODAwMCIsInNjb3BlcyI6Imh0dHBzOi8vcHVybC5pbXNnbG9iYWwub3JnL3NwZWMvbHRpLWFncy9zY29wZS9saW5laXRlbSBodHRwczovL3B1cmwuaW1zZ2xvYmFsLm9yZy9zcGVjL2x0aS1hZ3Mvc2NvcGUvcmVzdWx0LnJlYWRvbmx5IGh0dHBzOi8vcHVybC5pbXNnbG9i
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qHoEmKwI-Ow',                                                                                                                                                                                                      
        'HTTP_CONNECTION': 'keep-alive',                                                                                                                                                                         
        'HTTP_HOST': 'local.overhang.io:8000',                                                                                                                                                                   
        'HTTP_USER_AGENT': 'python-requests/2.27.1',                                                                                                                                                             
        'LC_ALL': 'en_US.UTF-8',                                                                                                                                                                                 
        'LMS_CFG': '/openedx/config/lms.env.json',                                                                                                                                                               
        'NO_PREREQ_INSTALL': '1',                                                                                                                                                                                
        'NO_PYTHON_UNINSTALL': '1',                                                                                                                                                                              
        'PATH': '/openedx/bin:/openedx/venv/bin:./node_modules/.bin:/openedx/nodeenv/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin',                                                          
        'PATH_INFO': '/api/lti_consumer/v1/lti/4/lti-ags',                                                                                                                                                       
        'PWD': '/openedx/edx-platform',                                                                                                                                                                          
        'QUERY_STRING': '',                                                                                                                                                                                      
        'REMOTE_ADDR': '172.25.0.1',                                                                                                                                                                             
        'REMOTE_HOST': '',                                                                                                                                                                                       
        'REQUEST_METHOD': 'GET',                                                                                                                                                                                 
        'REVISION_CFG': '/openedx/config/revisions.yml',                                                                                                                                                         
        'RUN_MAIN': 'true',                                                                                                                                                                                      
        'SCRIPT_NAME': '',                                                                                                                                                                                       
        'SERVER_NAME': 'local.overhang.io:8000',                                                                                                                                                                 
        'SERVER_PORT': '8000',                                                                                                                                                                                   
        'SERVER_PROTOCOL': 'HTTP/1.1',                                                                                                                                                                           
        'SERVER_SOFTWARE': 'WSGIServer/0.2',                                                                                                                                                                     
        'SERVICE_VARIANT': 'lms',                                                                                                                                                                                
        'SETTINGS': 'tutor.development',                                                                                                                                                                         
        'STUDIO_CFG': '/openedx/config/cms.env.json',                                                                                                                                                            
        'TERM': 'xterm',    
        'TZ': 'UTC',
        'UWSGI_WORKERS': '2',
        'VIRTUAL_ENV': '/openedx/venv/',
        'wsgi.errors': <_io.TextIOWrapper name='<stderr>' mode='w' encoding='utf-8'>,
        'wsgi.file_wrapper': <class 'wsgiref.util.FileWrapper'>,
        'wsgi.input': <django.core.handlers.wsgi.LimitedStream object at 0x7f879a4250d0>,
        'wsgi.multiprocess': False,
        'wsgi.multithread': True,
        'wsgi.run_once': False,
        'wsgi.url_scheme': 'http',
        'wsgi.version': (1, 0)},
        '_body': b'',
        '_cached_user': <django.contrib.auth.models.AnonymousUser object at 0x7f879a4252e0>,
        '_cors_enabled': True,
        '_current_scheme_host': 'http://local.overhang.io:8000',
        '_files': <MultiValueDict: {}>,
        '_messages': <django.contrib.messages.storage.session.SessionStorage object at 0x7f879a425f10>,
        '_post': <QueryDict: {}>,
        '_read_started': True,
        '_stream': <_io.BytesIO object at 0x7f87826b12c0>,
        'auth': None,
        'content_params': {},
        'content_type': 'text/plain',
        'environ': {'CONTENT_LENGTH': '',
                    'CONTENT_TYPE': 'text/plain',
                    'DEBIAN_FRONTEND': 'noninteractive',
                    'DJANGO_SETTINGS_MODULE': 'lms.envs.tutor.development',
                    'GATEWAY_INTERFACE': 'CGI/1.1',
                    'HOME': '/openedx',
                    'HOSTNAME': '678e52b7e5e1',
                    'HTTP_ACCEPT': 'application/vnd.ims.lis.v2.lineitemcontainer+json',
                    'HTTP_ACCEPT_ENCODING': 'gzip, deflate',
                    'HTTP_AUTHORIZATION': 'Bearer '
                                        'eyJhbGciOiJSUzI1NiIsImtpZCI6ImViN2MyYTJmLTExMzYtNGNiNi1iNGJhLTJiZjc5ZjA5M2Q0NCJ9.eyJzdWIiOiJmOTdjMmM3ZS0yZDUxLTRhM2YtYTUyMC05NzE4ZmJhN2U3ZDQiLCJpc3MiOiJodHRwOi8vbG9jYWwub3Zlcm
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        CqFw2UMbDimNtkojfMJKnYd02pAfFtqOb7CamIz6L-9P0O6iaYSnb-fSPVZZXyVRkK4SGtM_5QYgWraUzWmkxNPm0bdZu_nBm1OgekCAM16nlmjciCSDnB4q-OV9c0VmGHRcwvKB-1EYHz6sKKnw7TNwDggbgZ5uD_8Cf77f3CDgRL5kCn1wfIfzYtdsjuB2EjeMAVEsCYjg6yGZMPr
        zFaqHoEmKwI-Ow',
        'HTTP_CONNECTION': 'keep-alive',
        'HTTP_HOST': 'local.overhang.io:8000',
        'HTTP_USER_AGENT': 'python-requests/2.27.1',
        'LC_ALL': 'en_US.UTF-8',
        'LMS_CFG': '/openedx/config/lms.env.json',
        'NO_PREREQ_INSTALL': '1',
        'NO_PYTHON_UNINSTALL': '1',
        'PATH': '/openedx/bin:/openedx/venv/bin:./node_modules/.bin:/openedx/nodeenv/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin',
        'PATH_INFO': '/api/lti_consumer/v1/lti/4/lti-ags',
        'PWD': '/openedx/edx-platform',
        'QUERY_STRING': '',
        'REMOTE_ADDR': '172.25.0.1',
        'REMOTE_HOST': '',
        'REQUEST_METHOD': 'GET',                                                                                                                                                                              
        'REVISION_CFG': '/openedx/config/revisions.yml',
        'RUN_MAIN': 'true',
        'SCRIPT_NAME': '',
        'SERVER_NAME': 'local.overhang.io:8000',
        'SERVER_PORT': '8000',
        'SERVER_PROTOCOL': 'HTTP/1.1',
        'SERVER_SOFTWARE': 'WSGIServer/0.2',
        'SERVICE_VARIANT': 'lms',
        'SETTINGS': 'tutor.development',
        'STUDIO_CFG': '/openedx/config/cms.env.json',
        'TERM': 'xterm',
        'TZ': 'UTC',
        'UWSGI_WORKERS': '2',
        'VIRTUAL_ENV': '/openedx/venv/',
        'wsgi.errors': <_io.TextIOWrapper name='<stderr>' mode='w' encoding='utf-8'>,
        'wsgi.file_wrapper': <class 'wsgiref.util.FileWrapper'>,
        'wsgi.input': <django.core.handlers.wsgi.LimitedStream object at 0x7f879a4250d0>,
        'wsgi.multiprocess': False,
        'wsgi.multithread': True,
        'wsgi.run_once': False,
        'wsgi.url_scheme': 'http',
        'wsgi.version': (1, 0)
    },
    'headers': {'Content-Length': '', 'Content-Type': 'text/plain', 'Host': 'local.overhang.io:8000', 'User-Agent': 'python-requests/2.27.1', 'Accept-Encoding': 'gzip, deflate', 'Accept': 'application/vnd.ims.lis.v
    2.lineitemcontainer+json', 'Connection': 'keep-alive', 'Authorization': 'Bearer eyJhbGciOiJSUzI1NiIsImtpZCI6ImViN2MyYTJmLTExMzYtNGNiNi1iNGJhLTJiZjc5ZjA5M2Q0NCJ9.eyJzdWIiOiJmOTdjMmM3ZS0yZDUxLTRhM2YtYTUyMC05NzE4Zm
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    f3CDgRL5kCn1wfIfzYtdsjuB2EjeMAVEsCYjg6yGZMPrzFaqHoEmKwI-Ow'},
    'method': 'GET',
    'path': '/api/lti_consumer/v1/lti/4/lti-ags',
    'path_info': '/api/lti_consumer/v1/lti/4/lti-ags',
    'resolver_match': ResolverMatch(func=lti_consumer.plugin.views.LtiAgsLineItemViewset, args=(), kwargs={'lti_config_id': '4'}, url_name=lti-ags-view-list, app_names=['lti_consumer'], namespaces=['lti_consumer'],
    route=^api/lti_consumer/v1/lti/(?P<lti_config_id>[-\w]+)/lti-ags$),
    'session': <django.contrib.sessions.backends.cache.SessionStore object at 0x7f879a4253a0>,
    'site': <Site: local.overhang.io:8000>,
    'site_theme': None,
    'user': None,
    'view_name': 'LtiAgsLineItemViewset'
}

As far as I understand, this is not a bug in DarkLangMiddleware but in the Lti1p3ApiAuthentication authentication backend, as described by @Alain1405. Returning (None, None) in this backend has the effect of setting request.user to None:

xblock-lti-consumer/lti_consumer/lti_1p3/extensions/rest_framework/authentication.py

Line 79 in 4588b7a

return (None, None)

The DarkLangMiddleware fails because it is next in line in processing the response. Modifying the Darklang middleware does allow us to bypass the issue, but there are many places in the code base that assume that request.user is not None, so my (not-very-well-informed) opinion is that we should default to an anonymous user instead.

EDIT: hey I didn't notice @OlhaShyliaieva comment before posting mine :-/ Looks like we were working on this simultaneously.

[giovannicimolin]

@Alain1405 @OlhaShyliaieva @regisb Makes sense! Awesome deep dive investigating the issue. I don't see any other things that might be causing the issue, the LTI request is well-formed and coming in as expected.

Can one of you make a PR to change return (None, None) to return (AnonymousUser, None) on this line then? I'm a Core Contributor here and I can review/approve/merge.