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|
import warnings
from datetime import datetime, timedelta
from django import forms
from django.conf import settings
from django.contrib import messages
from django.contrib.admin import FieldListFilter
from django.contrib.admin.exceptions import (
DisallowedModelAdminLookup,
DisallowedModelAdminToField,
)
from django.contrib.admin.options import (
IS_FACETS_VAR,
IS_POPUP_VAR,
TO_FIELD_VAR,
IncorrectLookupParameters,
ShowFacets,
)
from django.contrib.admin.utils import (
build_q_object_from_lookup_parameters,
get_fields_from_path,
lookup_spawns_duplicates,
prepare_lookup_value,
quote,
)
from django.core.exceptions import (
FieldDoesNotExist,
ImproperlyConfigured,
SuspiciousOperation,
)
from django.core.paginator import InvalidPage
from django.db.models import Exists, F, Field, ManyToOneRel, OrderBy, OuterRef
from django.db.models.expressions import Combinable
from django.urls import reverse
from django.utils.deprecation import RemovedInDjango60Warning
from django.utils.http import urlencode
from django.utils.inspect import func_supports_parameter
from django.utils.timezone import make_aware
from django.utils.translation import gettext
# Changelist settings
ALL_VAR = "all"
ORDER_VAR = "o"
PAGE_VAR = "p"
SEARCH_VAR = "q"
ERROR_FLAG = "e"
IGNORED_PARAMS = (
ALL_VAR,
ORDER_VAR,
SEARCH_VAR,
IS_FACETS_VAR,
IS_POPUP_VAR,
TO_FIELD_VAR,
)
class ChangeListSearchForm(forms.Form):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
# Populate "fields" dynamically because SEARCH_VAR is a variable:
self.fields = {
SEARCH_VAR: forms.CharField(required=False, strip=False),
}
class ChangeList:
search_form_class = ChangeListSearchForm
def __init__(
self,
request,
model,
list_display,
list_display_links,
list_filter,
date_hierarchy,
search_fields,
list_select_related,
list_per_page,
list_max_show_all,
list_editable,
model_admin,
sortable_by,
search_help_text,
):
self.model = model
self.opts = model._meta
self.lookup_opts = self.opts
self.root_queryset = model_admin.get_queryset(request)
self.list_display = list_display
self.list_display_links = list_display_links
self.list_filter = list_filter
self.has_filters = None
self.has_active_filters = None
self.clear_all_filters_qs = None
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_max_show_all = list_max_show_all
self.model_admin = model_admin
self.preserved_filters = model_admin.get_preserved_filters(request)
self.sortable_by = sortable_by
self.search_help_text = search_help_text
# Get search parameters from the query string.
_search_form = self.search_form_class(request.GET)
if not _search_form.is_valid():
for error in _search_form.errors.values():
messages.error(request, ", ".join(error))
self.query = _search_form.cleaned_data.get(SEARCH_VAR) or ""
try:
self.page_num = int(request.GET.get(PAGE_VAR, 1))
except ValueError:
self.page_num = 1
self.show_all = ALL_VAR in request.GET
self.is_popup = IS_POPUP_VAR in request.GET
self.add_facets = model_admin.show_facets is ShowFacets.ALWAYS or (
model_admin.show_facets is ShowFacets.ALLOW and IS_FACETS_VAR in request.GET
)
self.is_facets_optional = model_admin.show_facets is ShowFacets.ALLOW
to_field = request.GET.get(TO_FIELD_VAR)
if to_field and not model_admin.to_field_allowed(request, to_field):
raise DisallowedModelAdminToField(
"The field %s cannot be referenced." % to_field
)
self.to_field = to_field
self.params = dict(request.GET.items())
self.filter_params = dict(request.GET.lists())
if PAGE_VAR in self.params:
del self.params[PAGE_VAR]
del self.filter_params[PAGE_VAR]
if ERROR_FLAG in self.params:
del self.params[ERROR_FLAG]
del self.filter_params[ERROR_FLAG]
self.remove_facet_link = self.get_query_string(remove=[IS_FACETS_VAR])
self.add_facet_link = self.get_query_string({IS_FACETS_VAR: True})
if self.is_popup:
self.list_editable = ()
else:
self.list_editable = list_editable
self.queryset = self.get_queryset(request)
self.get_results(request)
if self.is_popup:
title = gettext("Select %s")
elif self.model_admin.has_change_permission(request):
title = gettext("Select %s to change")
else:
title = gettext("Select %s to view")
self.title = title % self.opts.verbose_name
self.pk_attname = self.lookup_opts.pk.attname
def __repr__(self):
return "<%s: model=%s model_admin=%s>" % (
self.__class__.__qualname__,
self.model.__qualname__,
self.model_admin.__class__.__qualname__,
)
def get_filters_params(self, params=None):
"""
Return all params except IGNORED_PARAMS.
"""
params = params or self.filter_params
lookup_params = params.copy() # a dictionary of the query string
# Remove all the parameters that are globally and systematically
# ignored.
for ignored in IGNORED_PARAMS:
if ignored in lookup_params:
del lookup_params[ignored]
return lookup_params
def get_filters(self, request):
lookup_params = self.get_filters_params()
may_have_duplicates = False
has_active_filters = False
supports_request = func_supports_parameter(
self.model_admin.lookup_allowed, "request"
)
if not supports_request:
warnings.warn(
f"`request` must be added to the signature of "
f"{self.model_admin.__class__.__qualname__}.lookup_allowed().",
RemovedInDjango60Warning,
)
for key, value_list in lookup_params.items():
for value in value_list:
params = (key, value, request) if supports_request else (key, value)
if not self.model_admin.lookup_allowed(*params):
raise DisallowedModelAdminLookup(f"Filtering by {key} not allowed")
filter_specs = []
for list_filter in self.list_filter:
lookup_params_count = len(lookup_params)
if callable(list_filter):
# This is simply a custom list filter class.
spec = list_filter(request, lookup_params, self.model, self.model_admin)
else:
field_path = None
if isinstance(list_filter, (tuple, list)):
# This is a custom FieldListFilter class for a given field.
field, field_list_filter_class = list_filter
else:
# This is simply a field name, so use the default
# FieldListFilter class that has been registered for the
# type of the given field.
field, field_list_filter_class = list_filter, FieldListFilter.create
if not isinstance(field, Field):
field_path = field
field = get_fields_from_path(self.model, field_path)[-1]
spec = field_list_filter_class(
field,
request,
lookup_params,
self.model,
self.model_admin,
field_path=field_path,
)
# field_list_filter_class removes any lookup_params it
# processes. If that happened, check if duplicates should be
# removed.
if lookup_params_count > len(lookup_params):
may_have_duplicates |= lookup_spawns_duplicates(
self.lookup_opts,
field_path,
)
if spec and spec.has_output():
filter_specs.append(spec)
if lookup_params_count > len(lookup_params):
has_active_filters = True
if self.date_hierarchy:
# Create bounded lookup parameters so that the query is more
# efficient.
year = lookup_params.pop("%s__year" % self.date_hierarchy, None)
if year is not None:
month = lookup_params.pop("%s__month" % self.date_hierarchy, None)
day = lookup_params.pop("%s__day" % self.date_hierarchy, None)
try:
from_date = datetime(
int(year[-1]),
int(month[-1] if month is not None else 1),
int(day[-1] if day is not None else 1),
)
except ValueError as e:
raise IncorrectLookupParameters(e) from e
if day:
to_date = from_date + timedelta(days=1)
elif month:
# In this branch, from_date will always be the first of a
# month, so advancing 32 days gives the next month.
to_date = (from_date + timedelta(days=32)).replace(day=1)
else:
to_date = from_date.replace(year=from_date.year + 1)
if settings.USE_TZ:
from_date = make_aware(from_date)
to_date = make_aware(to_date)
lookup_params.update(
{
"%s__gte" % self.date_hierarchy: [from_date],
"%s__lt" % self.date_hierarchy: [to_date],
}
)
# At this point, all the parameters used by the various ListFilters
# have been removed from lookup_params, which now only contains other
# parameters passed via the query string. We now loop through the
# remaining parameters both to ensure that all the parameters are valid
# fields and to determine if at least one of them spawns duplicates. If
# the lookup parameters aren't real fields, then bail out.
try:
for key, value in lookup_params.items():
lookup_params[key] = prepare_lookup_value(key, value)
may_have_duplicates |= lookup_spawns_duplicates(self.lookup_opts, key)
return (
filter_specs,
bool(filter_specs),
lookup_params,
may_have_duplicates,
has_active_filters,
)
except FieldDoesNotExist as e:
raise IncorrectLookupParameters(e) from e
def get_query_string(self, new_params=None, remove=None):
if new_params is None:
new_params = {}
if remove is None:
remove = []
p = self.filter_params.copy()
for r in remove:
for k in list(p):
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(sorted(p.items()), doseq=True)
def get_results(self, request):
paginator = self.model_admin.get_paginator(
request, self.queryset, 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.
if self.model_admin.show_full_result_count:
full_result_count = self.root_queryset.count()
else:
full_result_count = None
can_show_all = result_count <= self.list_max_show_all
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.queryset._clone()
else:
try:
result_list = paginator.page(self.page_num).object_list
except InvalidPage:
raise IncorrectLookupParameters
self.result_count = result_count
self.show_full_result_count = self.model_admin.show_full_result_count
# Admin actions are shown if there is at least one entry
# or if entries are not counted because show_full_result_count is disabled
self.show_admin_actions = not self.show_full_result_count or bool(
full_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_default_ordering(self):
ordering = []
if self.model_admin.ordering:
ordering = self.model_admin.ordering
elif self.lookup_opts.ordering:
ordering = self.lookup_opts.ordering
return ordering
def get_ordering_field(self, field_name):
"""
Return the proper model field name corresponding to the given
field_name to use for ordering. field_name may either be the name of a
proper model field or the name of a method (on the admin or model) or a
callable with the 'admin_order_field' attribute. Return None if no
proper model field name can be matched.
"""
try:
field = self.lookup_opts.get_field(field_name)
return field.name
except FieldDoesNotExist:
# See whether field_name is a name of a non-field
# that allows sorting.
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)
if isinstance(attr, property) and hasattr(attr, "fget"):
attr = attr.fget
return getattr(attr, "admin_order_field", None)
def get_ordering(self, request, queryset):
"""
Return the list of ordering fields for the change list.
First check the get_ordering() method in model admin, then check
the object's default ordering. Then, any manually-specified ordering
from the query string overrides anything. Finally, a deterministic
order is guaranteed by calling _get_deterministic_ordering() with the
constructed ordering.
"""
params = self.params
ordering = list(
self.model_admin.get_ordering(request) or self._get_default_ordering()
)
if ORDER_VAR in params:
# Clear ordering and used params
ordering = []
order_params = params[ORDER_VAR].split(".")
for p in order_params:
try:
none, pfx, idx = p.rpartition("-")
field_name = self.list_display[int(idx)]
order_field = self.get_ordering_field(field_name)
if not order_field:
continue # No 'admin_order_field', skip it
if isinstance(order_field, OrderBy):
if pfx == "-":
order_field = order_field.copy()
order_field.reverse_ordering()
ordering.append(order_field)
elif hasattr(order_field, "resolve_expression"):
# order_field is an expression.
ordering.append(
order_field.desc() if pfx == "-" else order_field.asc()
)
# reverse order if order_field has already "-" as prefix
elif pfx == "-" and order_field.startswith(pfx):
ordering.append(order_field.removeprefix(pfx))
else:
ordering.append(pfx + order_field)
except (IndexError, ValueError):
continue # Invalid ordering specified, skip it.
# Add the given query's ordering fields, if any.
ordering.extend(queryset.query.order_by)
return self._get_deterministic_ordering(ordering)
def _get_deterministic_ordering(self, ordering):
"""
Ensure a deterministic order across all database backends. Search for a
single field or unique together set of fields providing a total
ordering. If these are missing, augment the ordering with a descendant
primary key.
"""
ordering = list(ordering)
ordering_fields = set()
total_ordering_fields = {"pk"} | {
field.attname
for field in self.lookup_opts.fields
if field.unique and not field.null
}
for part in ordering:
# Search for single field providing a total ordering.
field_name = None
if isinstance(part, str):
field_name = part.lstrip("-")
elif isinstance(part, F):
field_name = part.name
elif isinstance(part, OrderBy) and isinstance(part.expression, F):
field_name = part.expression.name
if field_name:
# Normalize attname references by using get_field().
try:
field = self.lookup_opts.get_field(field_name)
except FieldDoesNotExist:
# Could be "?" for random ordering or a related field
# lookup. Skip this part of introspection for now.
continue
# Ordering by a related field name orders by the referenced
# model's ordering. Skip this part of introspection for now.
if field.remote_field and field_name == field.name:
continue
if field.attname in total_ordering_fields:
break
ordering_fields.add(field.attname)
else:
# No single total ordering field, try unique_together and total
# unique constraints.
constraint_field_names = (
*self.lookup_opts.unique_together,
*(
constraint.fields
for constraint in self.lookup_opts.total_unique_constraints
),
)
for field_names in constraint_field_names:
# Normalize attname references by using get_field().
fields = [
self.lookup_opts.get_field(field_name) for field_name in field_names
]
# Composite unique constraints containing a nullable column
# cannot ensure total ordering.
if any(field.null for field in fields):
continue
if ordering_fields.issuperset(field.attname for field in fields):
break
else:
# If no set of unique fields is present in the ordering, rely
# on the primary key to provide total ordering.
ordering.append("-pk")
return ordering
def get_ordering_field_columns(self):
"""
Return a dictionary of ordering field column numbers and asc/desc.
"""
# We must cope with more than one column having the same underlying sort
# field, so we base things on column numbers.
ordering = self._get_default_ordering()
ordering_fields = {}
if ORDER_VAR not in self.params:
# for ordering specified on ModelAdmin or model Meta, we don't know
# the right column numbers absolutely, because there might be more
# than one column associated with that ordering, so we guess.
for field in ordering:
if isinstance(field, (Combinable, OrderBy)):
if not isinstance(field, OrderBy):
field = field.asc()
if isinstance(field.expression, F):
order_type = "desc" if field.descending else "asc"
field = field.expression.name
else:
continue
elif field.startswith("-"):
field = field.removeprefix("-")
order_type = "desc"
else:
order_type = "asc"
for index, attr in enumerate(self.list_display):
if self.get_ordering_field(attr) == field:
ordering_fields[index] = order_type
break
else:
for p in self.params[ORDER_VAR].split("."):
none, pfx, idx = p.rpartition("-")
try:
idx = int(idx)
except ValueError:
continue # skip it
ordering_fields[idx] = "desc" if pfx == "-" else "asc"
return ordering_fields
def get_queryset(self, request, exclude_parameters=None):
# First, we collect all the declared list filters.
(
self.filter_specs,
self.has_filters,
remaining_lookup_params,
filters_may_have_duplicates,
self.has_active_filters,
) = self.get_filters(request)
# Then, we let every list filter modify the queryset to its liking.
qs = self.root_queryset
for filter_spec in self.filter_specs:
if (
exclude_parameters is None
or filter_spec.expected_parameters() != exclude_parameters
):
new_qs = filter_spec.queryset(request, qs)
if new_qs is not None:
qs = new_qs
try:
# Finally, we apply the remaining lookup parameters from the query
# string (i.e. those that haven't already been processed by the
# filters).
q_object = build_q_object_from_lookup_parameters(remaining_lookup_params)
qs = qs.filter(q_object)
except (SuspiciousOperation, ImproperlyConfigured):
# Allow certain types of errors to be re-raised as-is so that the
# caller can treat them in a special way.
raise
except Exception as e:
# Every other error is caught with a naked except, because we don't
# have any other way of validating lookup parameters. 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, ValidationError, or ?.
raise IncorrectLookupParameters(e)
# Apply search results
qs, search_may_have_duplicates = self.model_admin.get_search_results(
request,
qs,
self.query,
)
# Set query string for clearing all filters.
self.clear_all_filters_qs = self.get_query_string(
new_params=remaining_lookup_params,
remove=self.get_filters_params(),
)
# Remove duplicates from results, if necessary
if filters_may_have_duplicates | search_may_have_duplicates:
qs = qs.filter(pk=OuterRef("pk"))
qs = self.root_queryset.filter(Exists(qs))
# Set ordering.
ordering = self.get_ordering(request, qs)
qs = qs.order_by(*ordering)
if not qs.query.select_related:
qs = self.apply_select_related(qs)
return qs
def apply_select_related(self, qs):
if self.list_select_related is True:
return qs.select_related()
if self.list_select_related is False:
if self.has_related_field_in_list_display():
return qs.select_related()
if self.list_select_related:
return qs.select_related(*self.list_select_related)
return qs
def has_related_field_in_list_display(self):
for field_name in self.list_display:
try:
field = self.lookup_opts.get_field(field_name)
except FieldDoesNotExist:
pass
else:
if isinstance(field.remote_field, ManyToOneRel):
# <FK>_id field names don't require a join.
if field_name != field.get_attname():
return True
return False
def url_for_result(self, result):
pk = getattr(result, self.pk_attname)
return reverse(
"admin:%s_%s_change" % (self.opts.app_label, self.opts.model_name),
args=(quote(pk),),
current_app=self.model_admin.admin_site.name,
)
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