20130209
========

UI-less Lino
------------

Started :lino:`/tutorials/uiless`.

The following problem took me some time.
Restoring the dumped fixture in our example failed with::

  WARNING Abandoning with 24 unsaved instances from fixtures\a.py:
  - auth.Permission {'id': [u'Permission with this ID already exists.'], '__all__':    [u'Permission with this Content type and Codename already exists.']} (24 object(s) with primary key 16, 17, 18, 1, 4, 7, 2, 5, 8, 3, 6, 9, 10, 11, 12, 19, 21, 23, 20, 22, 24, 13, 14, 15)

That's because these permission instances are being 
automatically created by 
`django.contrib.auth.management.create_permissions`
before the dumpy deserializer could restore them.
`create_permissions` is being invoked by the `post_sync` signal.
The problem is that `initdb` should not emit this `post_sync` 
signal at all.

I didn't find a less cruel method to solve this than amputating 
Django's `post_syncdb` signal::

    class NullSignal:
        def connect(*args,**kw):
            pass
        def send(*args,**kw):
            pass
    
    models.signals.post_syncdb = NullSignal()

This is done by the new `--dumped` option of loaddata.

But the story goes on in :lino:`0211`.