django1/django/contrib/admin/views/autocomplete.py

111 lines
4.1 KiB
Python

from django.apps import apps
from django.core.exceptions import FieldDoesNotExist, PermissionDenied
from django.http import Http404, JsonResponse
from django.views.generic.list import BaseListView
class AutocompleteJsonView(BaseListView):
"""Handle AutocompleteWidget's AJAX requests for data."""
paginate_by = 20
admin_site = None
def get(self, request, *args, **kwargs):
"""
Return a JsonResponse with search results as defined in
serialize_result(), by default:
{
results: [{id: "123" text: "foo"}],
pagination: {more: true}
}
"""
self.term, self.model_admin, self.source_field, to_field_name = self.process_request(request)
if not self.has_perm(request):
raise PermissionDenied
self.object_list = self.get_queryset()
context = self.get_context_data()
return JsonResponse({
'results': [
self.serialize_result(obj, to_field_name)
for obj in context['object_list']
],
'pagination': {'more': context['page_obj'].has_next()},
})
def serialize_result(self, obj, to_field_name):
"""
Convert the provided model object to a dictionary that is added to the
results list.
"""
return {'id': str(getattr(obj, to_field_name)), 'text': str(obj)}
def get_paginator(self, *args, **kwargs):
"""Use the ModelAdmin's paginator."""
return self.model_admin.get_paginator(self.request, *args, **kwargs)
def get_queryset(self):
"""Return queryset based on ModelAdmin.get_search_results()."""
qs = self.model_admin.get_queryset(self.request)
qs = qs.complex_filter(self.source_field.get_limit_choices_to())
qs, search_use_distinct = self.model_admin.get_search_results(self.request, qs, self.term)
if search_use_distinct:
qs = qs.distinct()
return qs
def process_request(self, request):
"""
Validate request integrity, extract and return request parameters.
Since the subsequent view permission check requires the target model
admin, which is determined here, raise PermissionDenied if the
requested app, model or field are malformed.
Raise Http404 if the target model admin is not configured properly with
search_fields.
"""
term = request.GET.get('term', '')
try:
app_label = request.GET['app_label']
model_name = request.GET['model_name']
field_name = request.GET['field_name']
except KeyError as e:
raise PermissionDenied from e
# Retrieve objects from parameters.
try:
source_model = apps.get_model(app_label, model_name)
except LookupError as e:
raise PermissionDenied from e
try:
source_field = source_model._meta.get_field(field_name)
except FieldDoesNotExist as e:
raise PermissionDenied from e
try:
remote_model = source_field.remote_field.model
except AttributeError as e:
raise PermissionDenied from e
try:
model_admin = self.admin_site._registry[remote_model]
except KeyError as e:
raise PermissionDenied from e
# Validate suitability of objects.
if not model_admin.get_search_fields(request):
raise Http404(
'%s must have search_fields for the autocomplete_view.' %
type(model_admin).__qualname__
)
to_field_name = getattr(source_field.remote_field, 'field_name', remote_model._meta.pk.attname)
to_field_name = remote_model._meta.get_field(to_field_name).attname
if not model_admin.to_field_allowed(request, to_field_name):
raise PermissionDenied
return term, model_admin, source_field, to_field_name
def has_perm(self, request, obj=None):
"""Check if user has permission to access the related model."""
return self.model_admin.has_view_permission(request, obj=obj)