django-categories/categories/api/viewsets.py

106 lines
3.4 KiB
Python

from django.utils.decorators import method_decorator
from django.views.decorators.cache import cache_page
from rest_framework import mixins, permissions, serializers, viewsets
from ..models import Category
class CategorySerializer(serializers.ModelSerializer):
children = serializers.SerializerMethodField(method_name="_get_children")
class Meta:
model = Category
fields = [
"name",
"slug",
"active",
"thumbnail",
"thumbnail_width",
"thumbnail_height",
"order",
"alternate_title",
"alternate_url",
"description",
"meta_keywords",
"meta_extra",
"children",
]
def _get_children(self, obj):
children = obj.get_children()
return CategorySerializer(children, many=True).data
countable_fields = [
f
for f in Category._meta.get_fields()
if f.is_relation and f.name not in ["parent", "children", "categoryrelation"]
]
for field in countable_fields:
CategorySerializer._declared_fields[f"{field.name}_count"] = serializers.SerializerMethodField()
def field_count(self, obj, field=field):
return getattr(obj, f"{field.name}_count", "-")
setattr(CategorySerializer, f"get_{field.name}_count", field_count)
CategorySerializer.Meta.fields += [f"{field.name}_count"]
CategorySerializer._declared_fields[f"{field.name}_count_cumulative"] = serializers.SerializerMethodField()
def field_count_cumulative(self, obj, field=field):
return getattr(obj, f"{field.name}_count_cumulative", "-")
setattr(CategorySerializer, f"get_{field.name}_count_cumulative", field_count_cumulative)
CategorySerializer.Meta.fields += [f"{field.name}_count_cumulative"]
class CategoryList(list): # To overcome problem with filters that require model in queryset
model = Category
# TODO: this function can be universally shared, maybe it can be moved to Categories models
def get_category_queryset(queryset=None, extra_filters=None, exclude_blank=False):
if not queryset:
queryset = Category.tree.filter(active=True)
if not extra_filters:
extra_filters = {}
for field in countable_fields:
queryset = Category.tree.add_related_count(
queryset, field.related_model, field.remote_field.name, f"{field.name}_count", extra_filters=extra_filters
)
queryset = Category.tree.add_related_count(
queryset,
field.related_model,
field.remote_field.name,
f"{field.name}_count_cumulative",
extra_filters=extra_filters,
cumulative=True,
)
if exclude_blank:
queryset = queryset.filter(asset_count_cumulative__gt=0)
return queryset
class CategoryViewSet(mixins.ListModelMixin, viewsets.GenericViewSet):
queryset = Category.tree.filter(active=True)
serializer_class = CategorySerializer
extra_count_filters = {}
def get_queryset(self, queryset=None):
if not queryset:
queryset = self.queryset
queryset = get_category_queryset(queryset, extra_filters=self.extra_count_filters)
queryset = CategoryList(queryset.get_cached_trees())
return queryset
permission_classes = (permissions.IsAuthenticatedOrReadOnly,)
@method_decorator(cache_page(60 * 60))
def list(self, *args, **kwargs):
return super().list(*args, **kwargs)