id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
30364	Django 2.2 check fails under sourceless project	Sascha P.	nobody	"Hi,
We are shipping python in docker containers in bytecode for legal purposes and obfuscation. With the new Django 2.2 this stopped working, due to an encoding issue. To reproduce this error we receive, we created a minimal dockerfile:

{{{

FROM python:alpine3.6
 
RUN apk upgrade --no-cache && \
    pip install Django==2.2.0 && \
    django-admin startproject mysite && \
    python3 mysite/manage.py makemigrations && \
    python3 -m compileall -b -f mysite && \
    find mysite -type f -name '*.py' | xargs rm && \
    mv mysite/manage.pyc mysite/manage.py && \
    python3 mysite/manage.py makemigrations
 
 
CMD /bin/sh
}}}

You will get this error:


{{{
Traceback (most recent call last):
  File ""/usr/local/lib/python3.6/site-packages/django/template/utils.py"", line 66, in __getitem__
    return self._engines[alias]
KeyError: 'django'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File ""mysite/manage.py"", line 21, in <module>
  File ""mysite/manage.py"", line 17, in main
  File ""/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py"", line 381, in execute_from_command_line
    utility.execute()
  File ""/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py"", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File ""/usr/local/lib/python3.6/site-packages/django/core/management/base.py"", line 323, in run_from_argv
    self.execute(*args, **cmd_options)
  File ""/usr/local/lib/python3.6/site-packages/django/core/management/base.py"", line 361, in execute
    self.check()
  File ""/usr/local/lib/python3.6/site-packages/django/core/management/base.py"", line 390, in check
    include_deployment_checks=include_deployment_checks,
  File ""/usr/local/lib/python3.6/site-packages/django/core/management/base.py"", line 377, in _run_checks
    return checks.run_checks(**kwargs)
  File ""/usr/local/lib/python3.6/site-packages/django/core/checks/registry.py"", line 72, in run_checks
    new_errors = check(app_configs=app_configs)
  File ""/usr/local/lib/python3.6/site-packages/django/contrib/admin/checks.py"", line 80, in check_dependencies
    for engine in engines.all():
  File ""/usr/local/lib/python3.6/site-packages/django/template/utils.py"", line 90, in all
    return [self[alias] for alias in self]
  File ""/usr/local/lib/python3.6/site-packages/django/template/utils.py"", line 90, in <listcomp>
    return [self[alias] for alias in self]
  File ""/usr/local/lib/python3.6/site-packages/django/template/utils.py"", line 81, in __getitem__
    engine = engine_cls(params)
  File ""/usr/local/lib/python3.6/site-packages/django/template/backends/django.py"", line 23, in __init__
    options.setdefault('file_charset', settings.FILE_CHARSET)
  File ""/usr/local/lib/python3.6/site-packages/django/conf/__init__.py"", line 134, in FILE_CHARSET
    stack = traceback.extract_stack()
  File ""/usr/local/lib/python3.6/traceback.py"", line 207, in extract_stack
    stack = StackSummary.extract(walk_stack(f), limit=limit)
  File ""/usr/local/lib/python3.6/traceback.py"", line 358, in extract
    f.line
  File ""/usr/local/lib/python3.6/traceback.py"", line 282, in line
    self._line = linecache.getline(self.filename, self.lineno).strip()
  File ""/usr/local/lib/python3.6/linecache.py"", line 16, in getline
    lines = getlines(filename, module_globals)
  File ""/usr/local/lib/python3.6/linecache.py"", line 47, in getlines
    return updatecache(filename, module_globals)
  File ""/usr/local/lib/python3.6/linecache.py"", line 137, in updatecache
    lines = fp.readlines()
  File ""/usr/local/lib/python3.6/codecs.py"", line 321, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x8d in position 4: invalid start byte
}}}


If you use Django==2.1.8 instead you will get the expected ""No changes detected"" and everything works fine. There has been some work around ""FILE_CHARSET"" with Django 2.2.0, so maybe thats where this comes from.

We normally always use the newest Django version, yet with this one we had to pin the version to 2.1.8.

If this is not a bug caused by Django, then Im sorry for reporting this, yet I hope that someone could point me to the right direction.

Best regards
Sascha
"	Bug	closed	Uncategorized	2.2	Normal	invalid	compileall, Django 2.2, encoding	Florian Apolloner	Unreviewed	0	0	0	0	0	0