Prevent the Python Format from Being Used with the loaddata and dumpdata Commands

[empty]

Ticket #4187 identifies a problem with the python serializer when attempting to deserialize data with the loaddata management command after it has been serialized with the dumpdata management command. It was determined that the python serializer should only be used for internal use and not available as a serializer format for these management commands.

We need to detect and prevent the python format from being used with the loaddata and dumpdata management commands and figure out an elegant way to make that clear in the django-admin.py / manage.py documentation.

[Simon G <dev@…>]

Thanks empty :)

[empty]

Added patch and tests

[empty]

Added patch and tests. Test pass fine but I am getting a piece of console output. If you can let me know how to suppress that I'll be happy to fix it.

[empty]

Never fails. Forgot the new fixture4.python file for the test.

[Jacob]

I don't like hardcoding "python" as a "bad" serializer. I think a better approach would be a flag on the serializer module itself marking the module as non-public.

[empty]

I didn't like that either. :) I figured you would suggest something more appropriate. Thanks for the pointer. I'll get it fixed up soon.

[empty]

Used flag in place of hardcoding

[empty]

Okay a new patch has been added that uses a flag. One other thing I noticed is that we have this construct in several places:

if not _serializers:
    _load_serializers()

Would it not make more sense to get rid of this and place the check in the _load_serializers function instead? The only place this function call is being made is from the init.py so there would not be any repercussions to the rest of the system.

[Malcolm Tredinnick]

I'm not going to commit the changes to tests/ in this patch because it's not silent. For some reason, output is leaking through, which is misleading, because the tests are passing. This looks like a side effect of calling management.call_command() and I'm not worried about it, since the patch works, and it's not worth holding up in order to mess around with the test infrastructure for this special case.

[Malcolm Tredinnick]

(In [6922]) Fixed #6110 -- Mark the python format serializer as for internal use only. Thanks, empty.