djangorestframework-chain 0.1.0

Chaining filtering through relations

To enable chained filtering through relations:

views.py

from rest_framework import viewsets
import django_filters
from rest_framework_chain import ChainedFilterSet, RelatedField

class PageFilter(ChainedFilterSet):
    title = django_filters.CharFilter(name='title')
    author = RelatedFilter(UserFilter, name='author')

# Just a regular FilterSet
class UserFilter(django_filters.FilterSet):
    username = django_filters.CharFilter(name='username')
    ...

# Then just use the PageFilter as you would any other FilterSet:

class PageView(viewsets.ModelViewSet):
    ...
    filter_class = PageFilter

then we can automatically chain our filters through the author relation, as so:

/api/page/?author__username=philipn

Allowing any lookup type on a field

We can use the AllLookupsFilter to allow all possible lookup types on a particular field. While we could otherwise specify these by hand, e.g.:

class ProductFilter(django_filters.FilterSet):
    min_price = django_filters.NumberFilter(name="price", lookup_type='gte')
    ...

to allow the price__gte lookup. But this gets cumbersome, and we sometimes want to allow any possible lookups on particular fields. We do this by using AllLookupsFilter:

views.py

from rest_framework import viewsets
import django_filters
from rest_framework_chain import ChainedFilterSet, AllLookupsFilter

class PageFilter(ChainedFilterSet):
    title = AllLookupsFilter(name='title')
    ...

then we can use any possible lookup on the title field, e.g.:

/api/page/?title__icontains=park

or

/api/page/?title__startswith=The

and also filter on the default lookup (exact), as usual:

/api/page/?title=The%20Park

Combining RelatedField and AllLookupsFilter

We can combine RelatedField and AllLookupsFilter:

from rest_framework import viewsets
import django_filters
from rest_framework_chain import ChainedFilterSet, RelatedField

class PageFilter(ChainedFilterSet):
    title = django_filters.CharFilter(name='title')
    author = RelatedFilter(UserFilter, name='author')

# Just a regular FilterSet
class UserFilter(ChainedFilterSet):
    username = AllLookupsFilter(name='username')
    ...

then we can filter like so:

/api/page/?author__username__icontains=john