from django.contrib.admin.filterspecs import FilterSpec
from django.contrib.admin.options import IncorrectLookupParameters
from django.contrib.admin.util import quote
from django.core.paginator import Paginator,InvalidPage
from django.db import models
from django.db.models.query import QuerySet
from django.utils.encoding import force_unicode,smart_str
from django.utils.translation import ugettext
from django.utils.http import urlencode
import operator
# The system will display a "Show all" link on the change list only if the
# total result count is less than or equal to this setting.
MAX_SHOW_ALL_ALLOWED = 200
# Changelist settings
ALL_VAR = 'all'
ORDER_VAR = 'o'
ORDER_TYPE_VAR = 'ot'
PAGE_VAR = 'p'
SEARCH_VAR = 'q'
TO_FIELD_VAR = 't'
IS_POPUP_VAR = 'pop'
ERROR_FLAG = 'e'
# Text to display within change-list table cells if the value is blank.
EMPTY_CHANGELIST_VALUE = '(None)'
class ChangeList(object):
def __init__(self, request, model, list_display, list_display_links, list_filter, date_hierarchy, search_fields, list_select_related, list_per_page, list_editable, model_admin):
self.model = model
self.opts = model._meta
self.lookup_opts = self.opts
self.root_query_set = model_admin.queryset(request)
self.list_display = list_display
self.list_display_links = list_display_links
self.list_filter = list_filter
self.date_hierarchy = date_hierarchy
self.search_fields = search_fields
self.list_select_related = list_select_related
self.list_per_page = list_per_page
self.list_editable = list_editable
self.model_admin = model_admin
# Get search parameters from the query string.
try:
self.page_num = int(request.GET.get(PAGE_VAR, 0))
except ValueError:
self.page_num = 0
self.show_all = ALL_VAR in request.GET
self.is_popup = IS_POPUP_VAR in request.GET
self.to_field = request.GET.get(TO_FIELD_VAR)
self.params = dict(request.GET.items())
if PAGE_VAR in self.params:
del self.params[PAGE_VAR]
if TO_FIELD_VAR in self.params:
del self.params[TO_FIELD_VAR]
if ERROR_FLAG in self.params:
del self.params[ERROR_FLAG]
self.order_field, self.order_type = self.get_ordering()
self.query = request.GET.get(SEARCH_VAR, '')
self.query_set = self.get_query_set()
self.get_results(request)
self.title = (self.is_popup and ugettext('Select %s') % force_unicode(self.opts.verbose_name) or ugettext('Select %s to change') % force_unicode(self.opts.verbose_name))
self.filter_specs, self.has_filters = self.get_filters(request)
self.pk_attname = self.lookup_opts.pk.attname
def get_filters(self, request):
filter_specs = []
if self.list_filter:
filter_fields = [self.lookup_opts.get_field(field_name) for field_name in self.list_filter]
for f in filter_fields:
spec = FilterSpec.create(f, request, self.params, self.model, self.model_admin)
if spec and spec.has_output():
filter_specs.append(spec)
return filter_specs, bool(filter_specs)
def get_query_string(self, new_params=None, remove=None):
if new_params is None: new_params = {}
if remove is None: remove = []
p = self.params.copy()
for r in remove:
for k in p.keys():
if k.startswith(r):
del p[k]
for k, v in new_params.items():
if v is None:
if k in p:
del p[k]
else:
p[k] = v
return '?%s' % urlencode(p)
def get_results(self, request):
paginator = Paginator(self.query_set, self.list_per_page)
# Get the number of objects, with admin filters applied.
result_count = paginator.count
# Get the total number of objects, with no admin filters applied.
# Perform a slight optimization: Check to see whether any filters were
# given. If not, use paginator.hits to calculate the number of objects,
# because we've already done paginator.hits and the value is cached.
if not self.query_set.query.where:
full_result_count = result_count
else:
full_result_count = self.root_query_set.count()
can_show_all = result_count <= MAX_SHOW_ALL_ALLOWED
multi_page = result_count > self.list_per_page
# Get the list of objects to display on this page.
if (self.show_all and can_show_all) or not multi_page:
result_list = self.query_set._clone()
else:
try:
result_list = paginator.page(self.page_num+1).object_list
except InvalidPage:
result_list = ()
self.result_count = result_count
self.full_result_count = full_result_count
self.result_list = result_list
self.can_show_all = can_show_all
self.multi_page = multi_page
self.paginator = paginator
def get_ordering(self):
lookup_opts, params = self.lookup_opts, self.params
# For ordering, first check the "ordering" parameter in the admin
# options, then check the object's default ordering. If neither of
# those exist, order descending by ID by default. Finally, look for
# manually-specified ordering from the query string.
ordering = self.model_admin.ordering or lookup_opts.ordering or ['-' + lookup_opts.pk.name]
if ordering[0].startswith('-'):
order_field, order_type = ordering[0][1:], 'desc'
else:
order_field, order_type = ordering[0], 'asc'
if ORDER_VAR in params:
try:
field_name = self.list_display[int(params[ORDER_VAR])]
try:
f = lookup_opts.get_field(field_name)
except models.FieldDoesNotExist:
# See whether field_name is a name of a non-field
# that allows sorting.
try:
if callable(field_name):
attr = field_name
elif hasattr(self.model_admin, field_name):
attr = getattr(self.model_admin, field_name)
else:
attr = getattr(self.model, field_name)
order_field = attr.admin_order_field
except AttributeError:
pass
else:
order_field = f.name
except (IndexError, ValueError):
pass # Invalid ordering specified. Just use the default.
if ORDER_TYPE_VAR in params and params[ORDER_TYPE_VAR] in ('asc', 'desc'):
order_type = params[ORDER_TYPE_VAR]
return order_field, order_type
def get_query_set(self):
qs = self.root_query_set
lookup_params = self.params.copy() # a dictionary of the query string
for i in (ALL_VAR, ORDER_VAR, ORDER_TYPE_VAR, SEARCH_VAR, IS_POPUP_VAR):
if i in lookup_params:
del lookup_params[i]
for key, value in lookup_params.items():
if not isinstance(key, str):
# 'key' will be used as a keyword argument later, so Python
# requires it to be a string.
del lookup_params[key]
lookup_params[smart_str(key)] = value
# if key ends with __in, split parameter into separate values
if key.endswith('__in'):
lookup_params[key] = value.split(',')
# if key ends with __isnull, special case '' and false
if key.endswith('__isnull'):
if value.lower() in ('', 'false'):
lookup_params[key] = False
else:
lookup_params[key] = True
# Apply lookup parameters from the query string.
try:
qs = qs.filter(**lookup_params)
# Naked except! Because we don't have any other way of validating "params".
# They might be invalid if the keyword arguments are incorrect, or if the
# values are not in the correct type, so we might get FieldError, ValueError,
# ValicationError, or ? from a custom field that raises yet something else
# when handed impossible data.
except:
raise IncorrectLookupParameters
# Use select_related() if one of the list_display options is a field
# with a relationship and the provided queryset doesn't already have
# select_related defined.
if not qs.query.select_related:
if self.list_select_related:
qs = qs.select_related()
else:
for field_name in self.list_display:
try:
f = self.lookup_opts.get_field(field_name)
except models.FieldDoesNotExist:
pass
else:
if isinstance(f.rel, models.ManyToOneRel):
qs = qs.select_related()
break
# Set ordering.
if self.order_field:
qs = qs.order_by('%s%s' % ((self.order_type == 'desc' and '-' or ''), self.order_field))
# Apply keyword searches.
def construct_search(field_name):
if field_name.startswith('^'):
return "%s__istartswith" % field_name[1:]
elif field_name.startswith('='):
return "%s__iexact" % field_name[1:]
elif field_name.startswith('@'):
return "%s__search" % field_name[1:]
else:
return "%s__icontains" % field_name
if self.search_fields and self.query:
for bit in self.query.split():
or_queries = [models.Q(**{construct_search(str(field_name)): bit}) for field_name in self.search_fields]
qs = qs.filter(reduce(operator.or_, or_queries))
for field_name in self.search_fields:
if '__' in field_name:
qs = qs.distinct()
break
return qs
def url_for_result(self, result):
return "%s/" % quote(getattr(result, self.pk_attname))
|