Django 管理中的默认筛选器

class MyModelAdmin(admin.ModelAdmin):


def changelist_view(self, request, extra_context=None):


if not request.GET.has_key('decommissioned__exact'):


q = request.GET.copy()
q['decommissioned__exact'] = 'N'
request.GET = q
request.META['QUERY_STRING'] = request.GET.urlencode()
return super(MyModelAdmin,self).changelist_view(request, extra_context=extra_context)

Note that if instead of pre-selecting a filter value you want to always pre-filter the data before showing it in the admin, you should override the ModelAdmin.queryset() method instead.

I know that is not the best solution, but i changed the index.html in the admin template, line 25 and 37 like this:

25: <th scope="row"><a href="\{\{ model.admin_url }}{% ifequal model.name "yourmodelname" %}?yourflag_flag__exact=1{% endifequal %}">\{\{ model.name }}</a></th>

37: <td><a href="\{\{ model.admin_url }}{% ifequal model.name "yourmodelname" %}?yourflag__exact=1{% endifequal %}" class="changelink">{% trans 'Change' %}</a></td>

Took ha22109's answer above and modified to allow the selection of "All" by comparing HTTP_REFERER and PATH_INFO.

class MyModelAdmin(admin.ModelAdmin):


def changelist_view(self, request, extra_context=None):


test = request.META['HTTP_REFERER'].split(request.META['PATH_INFO'])


if test[-1] and not test[-1].startswith('?'):
if not request.GET.has_key('decommissioned__exact'):


q = request.GET.copy()
q['decommissioned__exact'] = 'N'
request.GET = q
request.META['QUERY_STRING'] = request.GET.urlencode()
return super(MyModelAdmin,self).changelist_view(request, extra_context=extra_context)

def changelist_view( self, request, extra_context = None ):
default_filter = False
try:
ref = request.META['HTTP_REFERER']
pinfo = request.META['PATH_INFO']
qstr = ref.split( pinfo )


if len( qstr ) < 2:
default_filter = True
except:
default_filter = True


if default_filter:
q = request.GET.copy()
q['registered__exact'] = '1'
request.GET = q
request.META['QUERY_STRING'] = request.GET.urlencode()


return super( InterestAdmin, self ).changelist_view( request, extra_context = extra_context )

I had to make a modification to get filtering to work correctly. The previous solution worked for me when the page loaded. If an 'action' was performed, the filter went back to 'All' and not my default. This solution loads the admin change page with the default filter, but also maintains filter changes or the current filter when other activity occurs on the page. I haven't tested all cases, but in reality it may be limiting the setting of a default filter to occur only when the page loads.

def changelist_view(self, request, extra_context=None):
default_filter = False


try:
ref = request.META['HTTP_REFERER']
pinfo = request.META['PATH_INFO']
qstr = ref.split(pinfo)
querystr = request.META['QUERY_STRING']


# Check the QUERY_STRING value, otherwise when
# trying to filter the filter gets reset below
if querystr is None:
if len(qstr) < 2 or qstr[1] == '':
default_filter = True
except:
default_filter = True


if default_filter:
q = request.GET.copy()
q['registered__isnull'] = 'True'
request.GET = q
request.META['QUERY_STRING'] = request.GET.urlencode()


return super(MyAdmin, self).changelist_view(request, extra_context=extra_context)

In order to achieve this and have a usable 'All' link in your sidebar (ie one that shows all rather than showing pending), you'd need to create a custom list filter, inheriting from django.contrib.admin.filters.SimpleListFilter and filtering on 'pending' by default. Something along these lines should work:

from datetime import date


from django.utils.translation import ugettext_lazy as _
from django.contrib.admin import SimpleListFilter


class StatusFilter(SimpleListFilter):
title = _('Status')


parameter_name = 'status'


def lookups(self, request, model_admin):
return (
(None, _('Pending')),
('activate', _('Activate')),
('rejected', _('Rejected')),
('all', _('All')),
)


def choices(self, cl):
for lookup, title in self.lookup_choices:
yield {
'selected': self.value() == lookup,
'query_string': cl.get_query_string({
self.parameter_name: lookup,
}, []),
'display': title,
}


def queryset(self, request, queryset):
if self.value() in ('activate', 'rejected'):
return queryset.filter(status=self.value())
elif self.value() == None:
return queryset.filter(status='pending')




class Admin(admin.ModelAdmin):
list_filter = [StatusFilter]

EDIT: Requires Django 1.4 (thanks Simon)

A slight improvement on Greg's answer using DjangoChoices, Python >= 2.5 and of course Django >= 1.4.

from django.utils.translation import ugettext_lazy as _
from django.contrib.admin import SimpleListFilter


class OrderStatusFilter(SimpleListFilter):
title = _('Status')


parameter_name = 'status__exact'
default_status = OrderStatuses.closed


def lookups(self, request, model_admin):
return (('all', _('All')),) + OrderStatuses.choices


def choices(self, cl):
for lookup, title in self.lookup_choices:
yield {
'selected': self.value() == lookup if self.value() else lookup == self.default_status,
'query_string': cl.get_query_string({self.parameter_name: lookup}, []),
'display': title,
}


def queryset(self, request, queryset):
if self.value() in OrderStatuses.values:
return queryset.filter(status=self.value())
elif self.value() is None:
return queryset.filter(status=self.default_status)




class Admin(admin.ModelAdmin):
list_filter = [OrderStatusFilter]

Thanks to Greg for the nice solution!

I know this question is quite old now, but it's still valid. I believe this is the most correct way of doing this. It's essentially the same as Greg's method, but formulated as an extendible class for easy re-use.

from django.contrib.admin import SimpleListFilter
from django.utils.encoding import force_text
from django.utils.translation import ugettext as _


class DefaultListFilter(SimpleListFilter):
all_value = '_all'


def default_value(self):
raise NotImplementedError()


def queryset(self, request, queryset):
if self.parameter_name in request.GET and request.GET[self.parameter_name] == self.all_value:
return queryset


if self.parameter_name in request.GET:
return queryset.filter(**{self.parameter_name:request.GET[self.parameter_name]})


return queryset.filter(**{self.parameter_name:self.default_value()})


def choices(self, cl):
yield {
'selected': self.value() == self.all_value,
'query_string': cl.get_query_string({self.parameter_name: self.all_value}, []),
'display': _('All'),
}
for lookup, title in self.lookup_choices:
yield {
'selected': self.value() == force_text(lookup) or (self.value() == None and force_text(self.default_value()) == force_text(lookup)),
'query_string': cl.get_query_string({
self.parameter_name: lookup,
}, []),
'display': title,
}


class StatusFilter(DefaultListFilter):
title = _('Status ')
parameter_name = 'status__exact'


def lookups(self, request, model_admin):
return ((0,'activate'), (1,'pending'), (2,'rejected'))


def default_value(self):
return 1


class MyModelAdmin(admin.ModelAdmin):
list_filter = (StatusFilter,)

A bit off-topic but my search for a similar question led me here. I was looking to have a default query by a date (ie if no input is provided, show only objects with timestamp of 'Today'), which complicates the question a bit. Here is what I came up with:

from django.contrib.admin.options import IncorrectLookupParameters
from django.core.exceptions import ValidationError


class TodayDefaultDateFieldListFilter(admin.DateFieldListFilter):
""" If no date is query params are provided, query for Today """


def queryset(self, request, queryset):
try:
if not self.used_parameters:
now = datetime.datetime.now().replace(hour=0, minute=0, second=0, microsecond=0)
self.used_parameters = {
('%s__lt' % self.field_path): str(now + datetime.timedelta(days=1)),
('%s__gte' % self.field_path): str(now),
}
# Insure that the dropdown reflects 'Today'
self.date_params = self.used_parameters
return queryset.filter(**self.used_parameters)
except ValidationError, e:
raise IncorrectLookupParameters(e)


class ImagesAdmin(admin.ModelAdmin):
list_filter = (
('timestamp', TodayDefaultDateFieldListFilter),
)

This is a simple override of the default DateFieldListFilter. By setting self.date_params, it insures that the filter dropdown will update to whatever option matches the self.used_parameters. For this reason, you must insure that the self.used_parameters are exactly what would be used by one of those dropdown selections (ie, find out what the date_params would be when using the 'Today' or 'Last 7 Days' and construct the self.used_parameters to match those).

This was built to work with Django 1.4.10

Here is my generic solution using redirect, it just checks if there are any GET parameters, if none exist then it redirects with the default get parameter. I also have a list_filter set so it picks that up and displays the default.

from django.shortcuts import redirect


class MyModelAdmin(admin.ModelAdmin):


...


list_filter = ('status', )


def changelist_view(self, request, extra_context=None):
referrer = request.META.get('HTTP_REFERER', '')
get_param = "status__exact=5"
if len(request.GET) == 0 and '?' not in referrer:
return redirect("{url}?{get_parms}".format(url=request.path, get_parms=get_param))
return super(MyModelAdmin,self).changelist_view(request, extra_context=extra_context)

The only caveat is when you do a direct get to the page with "?" present in the url, there is no HTTP_REFERER set so it will use the default parameter and redirect. This is fine for me, it works great when you click through the admin filter.

UPDATE:

In order to get around the caveat, I ended up writing a custom filter function which simplified the changelist_view functionality. Here is the filter:

class MyModelStatusFilter(admin.SimpleListFilter):
title = _('Status')
parameter_name = 'status'


def lookups(self, request, model_admin):  # Available Values / Status Codes etc..
return (
(8, _('All')),
(0, _('Incomplete')),
(5, _('Pending')),
(6, _('Selected')),
(7, _('Accepted')),
)


def choices(self, cl):  # Overwrite this method to prevent the default "All"
from django.utils.encoding import force_text
for lookup, title in self.lookup_choices:
yield {
'selected': self.value() == force_text(lookup),
'query_string': cl.get_query_string({
self.parameter_name: lookup,
}, []),
'display': title,
}


def queryset(self, request, queryset):  # Run the queryset based on your lookup values
if self.value() is None:
return queryset.filter(status=5)
elif int(self.value()) == 0:
return queryset.filter(status__lte=4)
elif int(self.value()) == 8:
return queryset.all()
elif int(self.value()) >= 5:
return queryset.filter(status=self.value())
return queryset.filter(status=5)

And the changelist_view now only passes the default parameter if none are present. The idea was to get rid of the generics filters capability to view all by using no get parameters. To view all I assigned the status = 8 for that purpose.:

class MyModelAdmin(admin.ModelAdmin):


...


list_filter = ('status', )


def changelist_view(self, request, extra_context=None):
if len(request.GET) == 0:
get_param = "status=5"
return redirect("{url}?{get_parms}".format(url=request.path, get_parms=get_param))
return super(MyModelAdmin, self).changelist_view(request, extra_context=extra_context)

This may be an old thread, but thought I would add my solution as I couldn't find better answers on google searches.

Do what (not sure if its Deminic Rodger, or ha22109) answered in the ModelAdmin for changelist_view

class MyModelAdmin(admin.ModelAdmin):
list_filter = (CustomFilter,)


def changelist_view(self, request, extra_context=None):


if not request.GET.has_key('decommissioned__exact'):


q = request.GET.copy()
q['decommissioned__exact'] = 'N'
request.GET = q
request.META['QUERY_STRING'] = request.GET.urlencode()
return super(MyModelAdmin,self).changelist_view(request, extra_context=extra_context)

Then we need to create a custom SimpleListFilter

class CustomFilter(admin.SimpleListFilter):
title = 'Decommissioned'
parameter_name = 'decommissioned'  # i chose to change it


def lookups(self, request, model_admin):
return (
('All', 'all'),
('1', 'Decommissioned'),
('0', 'Active (or whatever)'),
)


# had to override so that we could remove the default 'All' option
# that won't work with our default filter in the ModelAdmin class
def choices(self, cl):
yield {
'selected': self.value() is None,
'query_string': cl.get_query_string({}, [self.parameter_name]),
# 'display': _('All'),
}
for lookup, title in self.lookup_choices:
yield {
'selected': self.value() == lookup,
'query_string': cl.get_query_string({
self.parameter_name: lookup,
}, []),
'display': title,
}


def queryset(self, request, queryset):
if self.value() == '1':
return queryset.filter(decommissioned=1)
elif self.value() == '0':
return queryset.filter(decommissioned=0)
return queryset

You can simply usereturn queryset.filter() or if self.value() is None and Override method of SimpleListFilter

from django.utils.encoding import force_text


def choices(self, changelist):
for lookup, title in self.lookup_choices:
yield {
'selected': force_text(self.value()) == force_text(lookup),
'query_string': changelist.get_query_string(
{self.parameter_name: lookup}, []
),
'display': title,
}

Here's the Cleanest version I was able to generate of a filter with a redefined 'All' and a Default value that is selected.

If shows me by default the Trips currently happening.

class HappeningTripFilter(admin.SimpleListFilter):
"""
Filter the Trips Happening in the Past, Future or now.
"""
default_value = 'now'
title = 'Happening'
parameter_name = 'happening'


def lookups(self, request, model_admin):
"""
List the Choices available for this filter.
"""
return (
('all', 'All'),
('future', 'Not yet started'),
('now', 'Happening now'),
('past', 'Already finished'),
)


def choices(self, changelist):
"""
Overwrite this method to prevent the default "All".
"""
value = self.value() or self.default_value
for lookup, title in self.lookup_choices:
yield {
'selected': value == force_text(lookup),
'query_string': changelist.get_query_string({
self.parameter_name: lookup,
}, []),
'display': title,
}


def queryset(self, request, queryset):
"""
Returns the Queryset depending on the Choice.
"""
value = self.value() or self.default_value
now = timezone.now()
if value == 'future':
return queryset.filter(start_date_time__gt=now)
if value == 'now':
return queryset.filter(start_date_time__lte=now, end_date_time__gte=now)
if value == 'past':
return queryset.filter(end_date_time__lt=now)
return queryset.all()

Created a reusable Filter sub-class, inspired by some of the answers here (mostly Greg's).

Advantages:

Reusable - Pluggable in any standard ModelAdmin classes

Extendable - Easy to add additional/custom logic for QuerySet filtering

Easy to use - In its most basic form, only one custom attribute and one custom method need to be implemented (apart from those required for SimpleListFilter subclassing)

Intuitive admin - The "All" filter link is working as expected; as are all the others

No redirects - No need to inspect GET request payload, agnostic of HTTP_REFERER (or any other request related stuff, in its basic form)

No (changelist) view manipulation - And no template manipulations (god forbid)

Code:

(most of the imports are just for type hints and exceptions)

from typing import List, Tuple, Any


from django.contrib.admin.filters import SimpleListFilter
from django.contrib.admin.options import IncorrectLookupParameters
from django.contrib.admin.views.main import ChangeList
from django.db.models.query import QuerySet
from django.utils.encoding import force_str
from django.utils.translation import gettext_lazy as _
from django.core.exceptions import ValidationError




class PreFilteredListFilter(SimpleListFilter):


# Either set this or override .get_default_value()
default_value = None


no_filter_value = 'all'
no_filter_name = _("All")


# Human-readable title which will be displayed in the
# right admin sidebar just above the filter options.
title = None


# Parameter for the filter that will be used in the URL query.
parameter_name = None


def get_default_value(self):
if self.default_value is not None:
return self.default_value
raise NotImplementedError(
'Either the .default_value attribute needs to be set or '
'the .get_default_value() method must be overridden to '
'return a URL query argument for parameter_name.'
)


def get_lookups(self) -> List[Tuple[Any, str]]:
"""
Returns a list of tuples. The first element in each
tuple is the coded value for the option that will
appear in the URL query. The second element is the
human-readable name for the option that will appear
in the right sidebar.
"""
raise NotImplementedError(
'The .get_lookups() method must be overridden to '
'return a list of tuples (value, verbose value).'
)


# Overriding parent class:
def lookups(self, request, model_admin) -> List[Tuple[Any, str]]:
return [(self.no_filter_value, self.no_filter_name)] + self.get_lookups()


# Overriding parent class:
def queryset(self, request, queryset: QuerySet) -> QuerySet:
"""
Returns the filtered queryset based on the value
provided in the query string and retrievable via
`self.value()`.
"""
if self.value() is None:
return self.get_default_queryset(queryset)
if self.value() == self.no_filter_value:
return queryset.all()
return self.get_filtered_queryset(queryset)


def get_default_queryset(self, queryset: QuerySet) -> QuerySet:
return queryset.filter(**{self.parameter_name: self.get_default_value()})


def get_filtered_queryset(self, queryset: QuerySet) -> QuerySet:
try:
return queryset.filter(**self.used_parameters)
except (ValueError, ValidationError) as e:
# Fields may raise a ValueError or ValidationError when converting
# the parameters to the correct type.
raise IncorrectLookupParameters(e)


# Overriding parent class:
def choices(self, changelist: ChangeList):
"""
Overridden to prevent the default "All".
"""
value = self.value() or force_str(self.get_default_value())
for lookup, title in self.lookup_choices:
yield {
'selected': value == force_str(lookup),
'query_string': changelist.get_query_string({self.parameter_name: lookup}),
'display': title,
}

Full usage example:

from django.contrib import admin
from .models import SomeModelWithStatus




class StatusFilter(PreFilteredListFilter):
default_value = SomeModelWithStatus.Status.FOO
title = _('Status')
parameter_name = 'status'


def get_lookups(self):
return SomeModelWithStatus.Status.choices




@admin.register(SomeModelWithStatus)
class SomeModelAdmin(admin.ModelAdmin):
list_filter = (StatusFilter, )

Hope this helps somebody; feedback always appreciated.

Using ha22109's answer I wrote a mixin for ModelAdmin class:

from urllib.parse import urlencode
from django.contrib.admin.views.main import SEARCH_VAR
from django.http import HttpRequest, QueryDict




class DefaultFilterMixin:


default_filters: Sequence[tuple[str, Any]] | dict[str, Any] | None = None


def get_default_filters(
self,
request: HttpRequest,
) -> Sequence[tuple[str, Any]] | dict[str, Any] | None:
return self.default_filters


def changelist_view(
self,
request: HttpRequest,
extra_context: dict[str, str] | None = None,
):
if request.method == 'GET' and not request.GET:
if default_filters := self.get_default_filters(request):
request.GET = QueryDict(
f"{urlencode(default_filters)}&{SEARCH_VAR}=",
encoding=request.encoding,
)
request.META['QUERY_STRING'] = request.GET.urlencode()


return super().changelist_view(request, extra_context=extra_context)

Simple example:

class MyModelAdmin(DefaultFilterMixin, admin.ModelAdmin):


default_filters = (("status__exact", "pending"),)
...

Or more complex dynamic filter for rangefilter.DateTimeRangeFilter:

class MyModelAdmin(DefaultFilterMixin, admin.ModelAdmin):


def get_default_filters(
self,
request: HttpRequest,
) -> Sequence[tuple[str, Any]] | dict[str, Any] | None:
now = timezone.now()
date_fmt = '%d.%m.%Y'
return (
('created_at__range__gte_0', now.strftime(date_fmt)),
('created_at__range__gte_1', '00:00:00'),
('created_at__range__lte_0', (now + timedelta(1)).strftime(date_fmt)),
('created_at__range__lte_1', '00:00:00'),
)

replying to the first answer (from Evgeni Shudzel) with the default mixin... here is a solution with less imports and complications

from urllib.parse import urlencode
from django.contrib.admin.views.main import SEARCH_VAR
from django.http import HttpRequest, QueryDict


class DefaultFilterMixin:
default_filters: None


def get_default_filters(self, request: HttpRequest):
return self.default_filters


def changelist_view(self, request: HttpRequest, extra_context=None):
if request.method == 'GET' and not request.GET:
if default_filters := self.get_default_filters(request):
request.GET = QueryDict(
f"{urlencode(default_filters)}&{SEARCH_VAR}=",
encoding=request.encoding,
)
request.META['QUERY_STRING'] = request.GET.urlencode()


return super().changelist_view(request, extra_context=extra_context)


class SampleUsageAdmin(DefaultFilterMixin, admin.ModelAdmin):
default_filters = (("fulfillments_complete__exact", "0"),)