Tab completion over Django model fields in IPython.

Example:

User.objects.filter(us<tab>

becomes:

User.objects.filter(username

and:

User.objects.filter(username__st<tab>

becomes:

User.objects.filter(username__startswith=

Related fields are also supported:

User.objects.filter(grou<tab>ps__<tab>permis<tab>sions__n<tab>ame__sta<tab>rtswith

Install it with `pip`:

$ pip install git+https://github.com/jnothman/django-tabcomplete

then add it to your Django project's settings.py:

INSTALLED_APPS = [
    ...
    'django_tabcomplete',
]

For users of the Django ORM who frequently construct custom queries in interactive shells, it can be a challenge to remember field names on inter-related models. For such situations was tab completion invented, but while IPython provides tab completion for named function arguments, this does not extend to dynamic keyword arguments (i.e. whose names are not provided in the code or docstring).

Currently tab completion is only supported on filter and exclude methods of Manager or QuerySet objects that are referred to by a variable name or a sequence of attribute lookups. Thus no completion is provided for:

User.objects.all().filter(us<tab>

Nor can we currently provide tab completion in Q objects, though they can perform the same function, or in aggregates to name fields, because the target model cannot be identified locally.

We intend to add tab completion for other QuerySet methods that take field names as keyword arguments or as positional strings.

Pull requests are welcome!