django-mongoengine-filter¶
django-mongoengine-filter
is a reusable Django application for allowing
users to filter mongoengine querysets dynamically. It’s very similar to
popular django-filter
library and is designed to be used as a drop-in
replacement (as much as it’s possible) strictly tied to MongoEngine
.
Full documentation on Read the docs.
Requirements¶
Python 3.7, 3.8, 3.9, 3.10 or 3.11.
MongoDB 3.x, 4.x, 5.x.
Django 2.2, 3.0, 3.1, 3.2, 4.0 or 4.1.
Installation¶
Install using pip:
pip install django-mongoengine-filter
Or latest development version:
pip install https://github.com/barseghyanartur/django-mongoengine-filter/archive/master.zip
Usage¶
Sample document
from mongoengine import fields, document
from .constants import PROFILE_TYPES, PROFILE_TYPE_FREE, GENDERS, GENDER_MALE
class Person(document.Document):
name = fields.StringField(
required=True,
max_length=255,
default="Robot",
verbose_name="Name"
)
age = fields.IntField(required=True, verbose_name="Age")
num_fingers = fields.IntField(
required=False,
verbose_name="Number of fingers"
)
profile_type = fields.StringField(
required=False,
blank=False,
null=False,
choices=PROFILE_TYPES,
default=PROFILE_TYPE_FREE,
)
gender = fields.StringField(
required=False,
blank=False,
null=False,
choices=GENDERS,
default=GENDER_MALE
)
def __str__(self):
return self.name
Sample filter
import django_mongoengine_filter
class PersonFilter(django_mongoengine_filter.FilterSet):
profile_type = django_mongoengine_filter.StringFilter()
ten_fingers = django_mongoengine_filter.MethodFilter(
action="ten_fingers_filter"
)
class Meta:
model = Person
fields = ["profile_type", "ten_fingers"]
def ten_fingers_filter(self, queryset, name, value):
if value == 'yes':
return queryset.filter(num_fingers=10)
return queryset
Sample view
With function-based views:
def person_list(request):
filter = PersonFilter(request.GET, queryset=Person.objects)
return render(request, "dfm_app/person_list.html", {"object_list": filter.qs})
Or class-based views:
from django_mongoengine_filter.views import FilterView
class PersonListView(FilterView):
filterset_class = PersonFilter
template_name = "dfm_app/person_list.html"
Sample template
<ul>
{% for obj in object_list %}
<li>{{ obj.name }} - {{ obj.age }}</li>
{% endfor %}
</ul>
Sample requests
GET /persons/
GET /persons/?profile_type=free&gender=male
GET /persons/?profile_type=free&gender=female
GET /persons/?profile_type=member&gender=female
GET /persons/?ten_fingers=yes
Development¶
Testing¶
To run tests in your working environment type:
pytest -vrx
To test with all supported Python versions type:
tox
Running MongoDB¶
The easiest way is to run it via Docker:
docker pull mongo:latest
docker run -p 27017:27017 mongo:latest
Writing documentation¶
Keep the following hierarchy.
=====
title
=====
header
======
sub-header
----------
sub-sub-header
~~~~~~~~~~~~~~
sub-sub-sub-header
^^^^^^^^^^^^^^^^^^
sub-sub-sub-sub-header
++++++++++++++++++++++
sub-sub-sub-sub-sub-header
**************************
License¶
GPL-2.0-only OR LGPL-2.1-or-later
Support¶
For any security issues contact me at the e-mail given in the Author section.
For overall issues, go to GitHub.
Documentation¶
Contents:
Filter Reference¶
This is a reference document with a list of the filters and their arguments.
Filters¶
CharFilter
¶
This filter does simple character matches, used with CharField
and
TextField
by default.
BooleanFilter
¶
This filter matches a boolean, either True
or False
, used with
BooleanField
and NullBooleanField
by default.
ChoiceFilter
¶
This filter matches an item of any type by choices, used with any field that
has choices
.
MultipleChoiceFilter
¶
The same as ChoiceFilter
except the user can select multiple items and it
selects the OR of all the choices.
DateFilter
¶
Matches on a date. Used with DateField
by default.
DateTimeFilter
¶
Matches on a date and time. Used with DateTimeField
by default.
TimeFilter
¶
Matches on a time. Used with TimeField
by default.
ModelChoiceFilter
¶
Similar to a ChoiceFilter
except it works with related models, used for
ForeignKey
by default.
ModelMultipleChoiceFilter
¶
Similar to a MultipleChoiceFilter
except it works with related models, used
for ManyToManyField
by default.
NumberFilter
¶
Filters based on a numerical value, used with IntegerField
, FloatField
,
and DecimalField
by default.
RangeFilter
¶
Filters where a value is between two numerical values.
DateRangeFilter
¶
Filter similar to the admin changelist date one, it has a number of common selections for working with date fields.
AllValuesFilter
¶
This is a ChoiceFilter
whose choices are the current values in the
database. So if in the DB for the given field you have values of 5, 7, and 9
each of those is present as an option. This is similar to the default behavior
of the admin.
Core Arguments¶
name
¶
The name of the field this filter is supposed to filter on, if this is not
provided it automatically becomes the filter’s name on the FilterSet
.
label
¶
The label as it will apear in the HTML, analogous to a form field’s label argument.
widget
¶
The django.form Widget class which will represent the Filter
. In addition
to the widgets that are included with Django that you can use there are
additional ones that django-filter provides which may be useful:
django_filters.widgets.LinkWidget
– this displays the options in a manner similar to the way the Django Admin does, as a series of links. The link for the selected option will haveclass="selected"
.
action
¶
An optional callable that tells the filter how to handle the queryset. It
receives a QuerySet
and the value to filter on and should return a
Queryset
that is filtered appropriately.
lookup_type
¶
The type of lookup that should be performed using the Django ORM. All the
normal options are allowed, and should be provided as a string. You can also
provide either None
or a list
or a tuple
. If None
is provided,
then the user can select the lookup type from all the ones available in the
Django ORM. If a list
or tuple
is provided, then the user can select
from those options.
distinct
¶
A boolean value that specifies whether the Filter will use distinct on the
queryset. This option can be used to eliminate duplicate results when using
filters that span related models. Defaults to False
.
exclude
¶
A boolean value that specifies whether the Filter should use filter
or exclude
on the queryset. Defaults to False
.
**kwargs
¶
Any extra keyword arguments will be provided to the accompanying form Field.
This can be used to provide arguments like choices
or queryset
.
Widget Reference¶
This is a reference document with a list of the provided widgets and their arguments.
LinkWidget
¶
This widget renders each option as a link, instead of an actual <input>. It has
one method that you can override for additional customization.
option_string()
should return a string with 3 Python keyword argument
placeholders:
attrs
: This is a string with all the attributes that will be on the final<a>
tag.query_string
: This is the query string for use in thehref
option on the<a>
element.label
: This is the text to be displayed to the user.
Using django-mongoengine-filter¶
django-mongoengine-filter provides a simple way to filter down a queryset based on
parameters a user provides. Say we have a Product
model and we want to let
our users filter which products they see on a list page.
The model¶
Let’s start with our model:
from django.db import models
class Product(models.Model):
name = models.CharField(max_length=255)
price = models.DecimalField()
description = models.TextField()
release_date = models.DateField()
manufacturer = models.ForeignKey(Manufacturer)
The filter¶
We have a number of fields and we want to let our users filter based on the
price or the release_date. We create a FilterSet
for this:
import django_mongoengine_filter
class ProductFilter(django_mongoengine_filter.FilterSet):
class Meta:
model = Product
fields = ['price', 'release_date']
As you can see this uses a very similar API to Django’s ModelForm
. Just
like with a ModelForm
we can also override filters, or add new ones using a
declarative syntax:
import django_filters
class ProductFilter(django_mongoengine_filter.FilterSet):
price = django_filters.NumberFilter(lookup_type='lt')
class Meta:
model = Product
fields = ['price', 'release_date']
Filters take a lookup_type
argument which specifies what lookup type to
use with Django’s ORM. So here when a user entered a price it would show all
Products with a price less than that.
It’s quite common to forget to set lookup type for `CharField`s/`TextField`s and wonder why search for “foo” doesn’t return result for “foobar”. It’s because default lookup type is exact text, but you probably want `icontains` lookup field.
Items in the fields
sequence in the Meta
class may include
“relationship paths” using Django’s __
syntax to filter on fields on a
related model:
class ProductFilter(django_mongoengine_filter.FilterSet):
class Meta:
model = Product
fields = ['manufacturer__country']
Filters also take any arbitrary keyword arguments which get passed onto the
django.forms.Field
initializer. These extra keyword arguments get stored
in Filter.extra
, so it’s possible to override the initializer of a
FilterSet
to add extra ones:
class ProductFilter(django_mongoengine_filter.FilterSet):
class Meta:
model = Product
fields = ['manufacturer']
def __init__(self, *args, **kwargs):
super(ProductFilter, self).__init__(*args, **kwargs)
self.filters['manufacturer'].extra.update(
{'empty_label': 'All Manufacturers'})
Like django.contrib.admin.ModelAdmin
does it is possible to override
default filters for all the models fields of the same kind using
filter_overrides
:
class ProductFilter(django_mongoengine_filter.FilterSet):
filter_overrides = {
models.CharField: {
'filter_class': django_filters.CharFilter,
'extra': lambda f: {
'lookup_type': 'icontains',
}
}
}
class Meta:
model = Product
fields = ['name']
The view¶
Now we need to write a view:
def product_list(request):
f = ProductFilter(request.GET, queryset=Product.objects)
return render_to_response('my_app/template.html', {'filter': f})
If a queryset argument isn’t provided then all the items in the default manager of the model will be used.
The URL conf¶
We need a URL pattern to call the view:
re_path(r'^list$', views.product_list)
The template¶
And lastly we need a template:
{% extends "base.html" %}
{% block content %}
<form action="" method="get">
{{ filter.form.as_p }}
<input type="submit" />
</form>
{% for obj in filter %}
{{ obj.name }} - ${{ obj.price }}<br />
{% endfor %}
{% endblock %}
And that’s all there is to it! The form
attribute contains a normal
Django form, and when we iterate over the FilterSet
we get the objects in
the resulting queryset.
Other Meta options¶
Ordering using order_by
¶
You can allow the user to control ordering by providing the
order_by
argument in the Filter’s Meta class. order_by
can be either a
list
or tuple
of field names, in which case those are the options, or
it can be a bool
which, if True, indicates that all fields that
the user can filter on can also be sorted on. An example or ordering using a list:
import django_filters
class ProductFilter(django_filters.FilterSet):
price = django_filters.NumberFilter(lookup_type='lt')
class Meta:
model = Product
fields = ['price', 'release_date']
order_by = ['price']
If you want to control the display of items in order_by
, you can set it to
a list or tuple of 2-tuples in the format (field_name, display_name)
.
This lets you override the displayed names for your ordering fields:
order_by = (
('name', 'Company Name'),
('average_rating', 'Stars'),
)
Note that the default query parameter name used for ordering is o
. You
can override this by setting an order_by_field
attribute on the
FilterSet
class to the string value you would like to use.
Custom Forms using form
¶
The inner Meta
class also takes an optional form
argument. This is a
form class from which FilterSet.form
will subclass. This works similar to
the form
option on a ModelAdmin.
Non-Meta options¶
Note that these options do not go in the Meta class, they are specified directly in your FilterSet class.
strict
¶
The strict
option controls whether results are returned when an invalid
value is specified by the user for any filter field. By default, strict
is
set to True
meaning that an empty queryset is returned if any field contains
an invalid value. You can loosen this behavior by setting strict
to
False
which will effectively ignore a filter field if its value is invalid.
Overriding FilterSet
methods¶
get_ordering_field()
¶
If you want to use a custom widget, or in any other way override the ordering
field you can override the get_ordering_field()
method on a FilterSet
.
This method just needs to return a Form Field.
Ordering on multiple fields, or other complex orderings can be achieved by
overriding the Filterset.get_order_by()
method. This is passed the selected
order_by
value, and is expected to return an iterable of values to pass to
QuerySet.order_by
. For example, to sort a User
table by last name, then
first name:
class UserFilter(django_filters.FilterSet):
class Meta:
order_by = (
('username', 'Username'),
('last_name', 'Last Name')
)
def get_order_by(self, order_value):
if order_value == 'last_name':
return ['last_name', 'first_name']
return super(UserFilter, self).get_order_by(order_value)
Generic View¶
In addition to the above usage there is also a class-based generic view
included in django-filter, which lives at django_filters.views.FilterView
.
You must provide either a model
or filterset_class
argument, similar to
ListView
in Django itself:
# urls.py
from django.urls import re_path
from django_filters.views import FilterView
from myapp.models import Product
urlpatterns = [
re_path(r'^list/$', FilterView.as_view(model=Product)),
]
You must provide a template at <app>/<model>_filter.html
which gets the
context parameter filter
. Additionally, the context will contain
object_list
which holds the filtered queryset.
A legacy functional generic view is still included in django-filter, although
its use is deprecated. It can be found at
django_filters.views.object_filter
. You must provide the same arguments
to it as the class based view:
# urls.py
from django.urls import re_path
from myapp.models import Product
urlpatterns = [
re_path(r'^list/$', 'django_filters.views.object_filter', {'model': Product}),
]
The needed template and its context variables will also be the same as the class-based view above.
Release history and notes¶
Sequence based identifiers are used for versioning (schema follows below):
major.minor[.revision]
It’s always safe to upgrade within the same minor version (for example, from 0.3 to 0.3.4).
Minor version changes might be backwards incompatible. Read the release notes carefully before upgrading (for example, when upgrading from 0.3.4 to 0.4).
All backwards incompatible changes are mentioned in this document.
0.4.2¶
2023-05-24
Fix AttributeError: ‘BaseFilterSet’ object has no attribute ‘is_valid’ issue.
0.4.1¶
2023-02-23
Fix issue with adding
help_text
.
0.4.0¶
2022-12-24
Drop support for Python < 3.7.
Drop support for Django < 2.2.
Tested against Python 3.9, 3.10 and 3.11.
Tested against Django 3.1, 3.2, 4.0 and 4.1.
Apply
black
,isort
andruff
.Fix GitHub CI.
0.3.5¶
2020-03-23
Tested against Python 3.8.
Tested against Django 3.0.
0.3.4¶
2019-04-04
Using lazy queries where possible.
0.3.3¶
2019-04-02
Tested against Django 2.2.
0.3.2¶
2019-04-01
Fixes in class-based views.
Addition to docs.
0.3.1¶
2019-03-26
More tests.
Addition to docs.
0.3¶
2019-03-25
Got status beta
Note
Namespace changed from django_filters_mongoengine to django_mongoengine_filter. Modify your imports accordingly.
Clean up.
Added docs, manifest, tox.
0.2¶
2019-03-25
Working method filters.
0.1¶
2019-03-25
Initial alpha release.