Chained select2

Drop support for Django 1.9

.gitignore

@@ -1,6 +1,3 @@
-
-testapp/tt.py
-
 *.pyc
 
 Django_Select2.egg-info
@@ -19,3 +16,7 @@ docs/_build
 env/
 venv/
 .cache/
+.tox/
+geckodriver.log
+ghostdriver.log
+.coverage

.travis.yml

@@ -1,38 +1,80 @@
 language: python
 sudo: false
+dist: trusty
 cache:
-  - pip
+- apt
+- pip
 services:
-  - memcached
+- redis
+addons:
+ firefox: latest
+ apt:
+    sources:
+    - google-chrome
+    packages:
+    - google-chrome-stable
+    - python3-enchant
+    - python-enchant
+    - graphviz
 python:
   - "2.7"
-  - "3.3"
-  - "3.4"
-  - "pypy"
-  - "pypy3"
+  - "3.5"
+  - "3.6"
 env:
   global:
-    - DISPLAY=:99.0
+  - DISPLAY=:99.0
+  - GECKO_DRIVER_VERSION=v0.14.0
   matrix:
-    - DJANGO="Django<1.8,>=1.7"
-    - DJANGO="Django<1.9,>=1.8"
-    - DJANGO="-e git+https://github.com/django/django.git@master#egg=Django"
+  - DJANGO=18
+  - DJANGO=110
+  - DJANGO=111
+  - DJANGO=master
+  - TOXENV=qa
+  - TOXENV=docs
 matrix:
   fast_finish: true
   allow_failures:
-    - env: DJANGO="-e git+https://github.com/django/django.git@master#egg=Django"
+  - env: DJANGO=master
+  exclude:
+  - env: DJANGO=master
+    python: "2.7"
+  - env: TOXENV=qa
+    python: "2.7"
+  - env: TOXENV=qa
+    python: "3.5"
+  - env: TOXENV=docs
+    python: "2.7"
+  - env: TOXENV=docs
+    python: "3.5"
 install:
-  - pip install --upgrade pip
-  - pip install -r requirements_dev.txt
-  - if [[ $TRAVIS_PYTHON_VERSION == 2* ]] || [[ $TRAVIS_PYTHON_VERSION == pypy ]]; then pip install python-memcached; fi
-  - if [[ $TRAVIS_PYTHON_VERSION == 3* ]] || [[ $TRAVIS_PYTHON_VERSION == pypy3 ]]; then pip install python3-memcached; fi
-  - pip install $DJANGO
-  - pip install coveralls
-  - sh -e /etc/init.d/xvfb start
+- pip install --upgrade pip tox
+- pip install -U coveralls
+- sh -e /etc/init.d/xvfb start
+before_script:
+- mkdir bin
+- curl -O https://chromedriver.storage.googleapis.com/2.27/chromedriver_linux64.zip
+- unzip chromedriver_linux64.zip -d bin
+- curl -Lo geckodriver.tar.gz "https://github.com/mozilla/geckodriver/releases/download/${GECKO_DRIVER_VERSION}/geckodriver-${GECKO_DRIVER_VERSION}-linux64.tar.gz"
+- tar xzf geckodriver.tar.gz -C bin
+- PATH=$PATH:$PWD/bin
+- nvm install --lts
+- npm install -g standard
+- |
+  if [[ -z $TOXENV ]]; then
+    export TOXENV=py$(echo $TRAVIS_PYTHON_VERSION | sed -e 's/\.//g')-dj$DJANGO
+  fi
+- echo $TOXENV
 script:
-  - isort --check-only --recursive --diff .
-  - flake8 --jobs=2 .
-  - pep257 django_select2
-  - coverage run --source=django_select2 runtests.py
+- tox -e $TOXENV
+- standard
 after_success:
-  - coveralls
+- coveralls
+deploy:
+  provider: pypi
+  user: codingjoe
+  password:
+    secure: fEP9K7y0ZF9fRvQEUN4kgPXQEZvi3Cx3ikUebG2UM/2uhcaUQm0+KpgZ2S+lvOTYcBnNgzPzFsVIZMcVcTxwIKuQDEMq9y2eop2hnisb9KXsIm9qPYSzOnRm74VuiOt4hNOZMe0qVBK2cO3vC9NDXuzdI8A0JynJhthfl4t+kFM=
+  on:
+    tags: true
+    distributions: sdist bdist_wheel
+    repo: applegrew/django-select2

CHANGELOG.md

@@ -1,6 +1,77 @@
 Changelog Summary
 =================
 
+### v5.10.0
+* Add support for dependent select fields [321](github.com/applegrew/django-select2/pull/321/).
+
+### v5.9.0
+* Add support for Django 1.11 LTS
+* Drop support for Django 1.9
+
+### v5.8.10
+* Fixes tests for Django 1.10+
+* retain order of choices [299](https://github.com/applegrew/django-select2/pull/299)
+
+### v5.8.9
+* Fixes tests.  No functional change from 5.8.8.
+
+### v5.8.8
+* Upgrade Select2 to version 4.0.3
+
+### v5.8.7
+* Fix #285 -- Do not evaluate queryset in `render_options`.
+
+### v5.8.3
+* Remove six dependency -- User django.utils.six instead.
+
+### v5.8.2
+* Fixes #260 -- Fixes bug in render choices
+
+### v5.8.0
+* Changed signature of `render` and `render_choices` to satisfy Django 1.10 changes.
+* Changed widgets' inheritance tree to be more consistent.
+
+### v5.7.1
+* Fixes pickle bug of lazy object
+
+### v5.7.0
+* Security fix that allows a `field_id` to only be used for the intended JSON endpoint.
+  
+      Prior to that change you could use any `field_id` on any select2 JSON endpoint.
+      Even if the id was intended to be used on a private endpoint if could be used on
+      the default one and therefore leak sensitive data.
+      
+* Breaking change on how `Heavy` widgets are being cached.
+      
+      Heavy widgets used to add themselves to the cache. Now they add a dictionary to
+      the cache containing themselves and the target url.
+      
+      ```python
+      {
+          'widget': self,
+          'url': self.get_url(),
+      }
+      ```
+
+### v5.6.0
+* Added `label_from_instance` method for model widgets to define custom option labels.
+
+### v5.5.0
+* Added settings to delivery static assets from different source.
+
+### v5.4.2
+* Fixed initial data not being shown for heavy widgets.
+
+### v5.4.1
+* Fixed memory leak in `ModelSelect2Mixin` and subclasses
+
+### v5.4.0
+* Added `Select2TagWidget` a light widget with tagging support
+
+### v5.3.0
+* Added djangoSelect2 jQuery plugin to support
+  dynamic field initialisation
+
 ### v5.2.0
 * Added pagination
 

MANIFEST.in

@@ -3,3 +3,6 @@ recursive-include django_select2/static *.*
 recursive-exclude django_select2/static .DS_Store
 exclude requirements_dev.txt
 prune tests
+
+[bdist_wheel]
+universal=1

README.md

@@ -3,7 +3,7 @@ Django-Select2
 
 [![PyPi Version](https://img.shields.io/pypi/v/Django-Select2.svg)](https://pypi.python.org/pypi/Django-Select2/)
 [![Build Status](https://travis-ci.org/applegrew/django-select2.svg?branch=master)](https://travis-ci.org/applegrew/django-select2)
-[![Test Coverage](https://coveralls.io/repos/applegrew/django-select2/badge.png?branch=master)](https://coveralls.io/r/applegrew/django-select2)
+[![Test Coverage](https://coveralls.io/repos/applegrew/django-select2/badge.svg?branch=master)](https://coveralls.io/r/applegrew/django-select2)
 [![GitHub license](https://img.shields.io/badge/license-APL2-blue.svg)](https://raw.githubusercontent.com/applegrew/django-select2/master/LICENSE.txt)
 [![Join the chat at https://gitter.im/applegrew/django-select2](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/applegrew/django-select2?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 
@@ -54,7 +54,7 @@ Major changes:
 ## Documentation
 
 
-Documentation available at http://django-select2.readthedocs.org/.
+Documentation available at http://django-select2.readthedocs.io/.
 
 ## External Dependencies
 

django_select2/__init__.py

@@ -2,11 +2,11 @@
 """
 This is a Django_ integration of Select2_.
 
-The app includes Select2 driven Django Widgets and Form Fields.
+The application includes Select2 driven Django Widgets and Form Fields.
 
 .. _Django: https://www.djangoproject.com/
 .. _Select2: http://ivaynberg.github.com/select2/
 
 """
 
-__version__ = "5.2.1"
+__version__ = "5.10.0"

django_select2/cache.py

@@ -1,11 +1,11 @@
 # -*- coding: utf-8 -*-
 """
-Shared memory across multiple machines to the heavy ajax lookups.
+Shared memory across multiple machines to the heavy AJAX lookups.
 
 Select2 uses django.core.cache_ to share fields across
 multiple threads and even machines.
 
-Select2 uses the cabhe backend defind in the setting
+Select2 uses the cache backend defined in the setting
 ``SELECT2_CACHE_BACKEND`` [default=``default``].
 
 It is advised to always setup a separate cache server for Select2.

django_select2/conf.py

@@ -9,7 +9,6 @@ __all__ = ('settings', 'Select2Conf')
 
 
 class Select2Conf(AppConf):
-
     """Settings for Django-Select2."""
 
     CACHE_BACKEND = 'default'
@@ -49,5 +48,33 @@ class Select2Conf(AppConf):
     It has set `select2_` as a default value, which you can change if needed.
     """
 
+    JS = '//cdnjs.cloudflare.com/ajax/libs/select2/4.0.3/js/select2.min.js'
+    """
+    The URI for the Select2 JS file. By default this points to the Cloudflare CDN.
+
+    If you want to select the version of the JS library used, or want to serve it from
+    the local 'static' resources, add a line to your settings.py like so::
+
+        SELECT2_JS = 'assets/js/select2.min.js'
+
+    .. tip:: Change this setting to a local asset in your development environment to
+        develop without an Internet connection.
+    """
+
+    CSS = '//cdnjs.cloudflare.com/ajax/libs/select2/4.0.3/css/select2.min.css'
+    """
+    The URI for the Select2 CSS file. By default this points to the Cloudflare CDN.
+
+    If you want to select the version of the library used, or want to serve it from
+    the local 'static' resources, add a line to your settings.py like so::
+
+        SELECT2_CSS = 'assets/css/select2.css'
+
+    .. tip:: Change this setting to a local asset in your development environment to
+        develop without an Internet connection.
+    """
+
     class Meta:
+        """Prefix for all Django-Select2 settings."""
+
         prefix = 'SELECT2'

django_select2/forms.py

@@ -49,20 +49,26 @@ Light widgets are normally named, i.e. there is no
 from __future__ import absolute_import, unicode_literals
 
 from functools import reduce
+from itertools import chain
+from pickle import PicklingError
 
 from django import forms
 from django.core import signing
-from django.core.urlresolvers import reverse_lazy
 from django.db.models import Q
 from django.forms.models import ModelChoiceIterator
 from django.utils.encoding import force_text
+from django.utils.six.moves.cPickle import PicklingError as cPicklingError
 
 from .cache import cache
 from .conf import settings
 
+try:
+    from django.urls import reverse
+except ImportError:
+    from django.core.urlresolvers import reverse
+
 
 class Select2Mixin(object):
-
     """
     The base mixin of all Select2 widgets.
 
@@ -71,9 +77,9 @@ class Select2Mixin(object):
     form media.
     """
 
-    def build_attrs(self, extra_attrs=None, **kwargs):
+    def build_attrs(self, *args, **kwargs):
         """Add select2 data attributes."""
-        attrs = super(Select2Mixin, self).build_attrs(extra_attrs=extra_attrs, **kwargs)
+        attrs = super(Select2Mixin, self).build_attrs(*args, **kwargs)
         if self.is_required:
             attrs.setdefault('data-allow-clear', 'false')
         else:
@@ -87,10 +93,16 @@ class Select2Mixin(object):
             attrs['class'] = 'django-select2'
         return attrs
 
-    def render_options(self, choices, selected_choices):
+    def optgroups(self, name, value, attrs=None):
+        """Add empty option for clearable selects."""
+        if not self.is_required and not self.allow_multiple_selected:
+            self.choices = list(chain([('', '')], self.choices))
+        return super(Select2Mixin, self).optgroups(name, value, attrs=attrs)
+
+    def render_options(self, *args, **kwargs):
         """Render options including an empty one, if the field is not required."""
-        output = '<option></option>' if not self.is_required else ''
-        output += super(Select2Mixin, self).render_options(choices, selected_choices)
+        output = '<option value=""></option>' if not self.is_required and not self.allow_multiple_selected else ''
+        output += super(Select2Mixin, self).render_options(*args, **kwargs)
         return output
 
     def _get_media(self):
@@ -101,16 +113,25 @@ class Select2Mixin(object):
             https://docs.djangoproject.com/en/1.8/topics/forms/media/#media-as-a-dynamic-property
         """
         return forms.Media(
-            js=('//cdnjs.cloudflare.com/ajax/libs/select2/4.0.0/js/select2.min.js',
-                'django_select2/django_select2.js'),
-            css={'screen': ('//cdnjs.cloudflare.com/ajax/libs/select2/4.0.0/css/select2.min.css',)}
+            js=(settings.SELECT2_JS, 'django_select2/django_select2.js'),
+            css={'screen': (settings.SELECT2_CSS,)}
         )
 
     media = property(_get_media)
 
 
-class Select2Widget(Select2Mixin, forms.Select):
+class Select2TagMixin(object):
+    """Mixin to add select2 tag functionality."""
 
+    def build_attrs(self, *args, **kwargs):
+        """Add select2's tag attributes."""
+        self.attrs.setdefault('data-minimum-input-length', 1)
+        self.attrs.setdefault('data-tags', 'true')
+        self.attrs.setdefault('data-token-separators', '[",", " "]')
+        return super(Select2TagMixin, self).build_attrs(*args, **kwargs)
+
+
+class Select2Widget(Select2Mixin, forms.Select):
     """
     Select2 drop in widget.
 
@@ -135,7 +156,6 @@ class Select2Widget(Select2Mixin, forms.Select):
 
 
 class Select2MultipleWidget(Select2Mixin, forms.SelectMultiple):
-
     """
     Select2 drop in widget for multiple select.
 
@@ -145,36 +165,67 @@ class Select2MultipleWidget(Select2Mixin, forms.SelectMultiple):
     pass
 
 
-class HeavySelect2Mixin(Select2Mixin):
+class Select2TagWidget(Select2TagMixin, Select2Mixin, forms.SelectMultiple):
+    """
+    Select2 drop in widget for for tagging.
 
-    """Mixin that adds select2's ajax options and registers itself on django's cache."""
+    Example for :class:`.django.contrib.postgres.fields.ArrayField`::
 
-    def __init__(self, **kwargs):
+        class MyWidget(Select2TagWidget):
+
+            def value_from_datadict(self, data, files, name):
+                values = super(MyWidget, self).value_from_datadict(data, files, name):
+                return ",".join(values)
+
+    """
+
+    pass
+
+
+class HeavySelect2Mixin(object):
+    """Mixin that adds select2's AJAX options and registers itself on Django's cache."""
+
+    dependent_fields = {}
+
+    def __init__(self, attrs=None, choices=(), **kwargs):
         """
         Return HeavySelect2Mixin.
 
-        :param data_view: url pattern name
-        :type data_view: str
-        :param data_url: url
-        :type data_url: str
-        :return:
+        Args:
+            data_view (str): URL pattern name
+            data_url (str): URL
+            dependent_fields (dict): Dictionary of dependent parent fields.
+                The value of the dependent field will be passed as to :func:`.filter_queryset`.
+                It can be used to further restrict the search results. For example, a city
+                widget could be dependent on a country.
+                Key is a name of a field in a form.
+                Value is a name of a field in a model (used in `queryset`).
         """
+        self.choices = choices
+        if attrs is not None:
+            self.attrs = attrs.copy()
+        else:
+            self.attrs = {}
+
         self.data_view = kwargs.pop('data_view', None)
         self.data_url = kwargs.pop('data_url', None)
+
+        dependent_fields = kwargs.pop('dependent_fields', None)
+        if dependent_fields is not None:
+            self.dependent_fields = dict(dependent_fields)
         if not (self.data_view or self.data_url):
             raise ValueError('You must ether specify "data_view" or "data_url".')
         self.userGetValTextFuncName = kwargs.pop('userGetValTextFuncName', 'null')
-        super(HeavySelect2Mixin, self).__init__(**kwargs)
 
     def get_url(self):
-        """Return url from instance or by reversing :attr:`.data_view`."""
+        """Return URL from instance or by reversing :attr:`.data_view`."""
         if self.data_url:
             return self.data_url
-        return reverse_lazy(self.data_view)
+        return reverse(self.data_view)
 
-    def build_attrs(self, extra_attrs=None, **kwargs):
-        """Set select2's ajax attributes."""
-        attrs = super(HeavySelect2Mixin, self).build_attrs(extra_attrs=extra_attrs, **kwargs)
+    def build_attrs(self, *args, **kwargs):
+        """Set select2's AJAX attributes."""
+        attrs = super(HeavySelect2Mixin, self).build_attrs(*args, **kwargs)
 
         # encrypt instance Id
         self.widget_id = signing.dumps(id(self))
@@ -184,13 +235,15 @@ class HeavySelect2Mixin(Select2Mixin):
         attrs.setdefault('data-ajax--cache', "true")
         attrs.setdefault('data-ajax--type', "GET")
         attrs.setdefault('data-minimum-input-length', 2)
+        if self.dependent_fields:
+            attrs.setdefault('data-select2-dependent-fields', " ".join(self.dependent_fields))
 
         attrs['class'] += ' django-select2-heavy'
         return attrs
 
-    def render(self, name, value, attrs=None, choices=()):
+    def render(self, *args, **kwargs):
         """Render widget and register it in Django's cache."""
-        output = super(HeavySelect2Mixin, self).render(name, value, attrs=attrs, choices=choices)
+        output = super(HeavySelect2Mixin, self).render(*args, **kwargs)
         self.set_to_cache()
         return output
 
@@ -198,34 +251,52 @@ class HeavySelect2Mixin(Select2Mixin):
         return "%s%s" % (settings.SELECT2_CACHE_PREFIX, id(self))
 
     def set_to_cache(self):
-        """Add widget object to Djnago's cache."""
-        cache.set(self._get_cache_key(), self)
+        """
+        Add widget object to Django's cache.
 
-    def render_options(self, choices, selected_choices):
+        You may need to overwrite this method, to pickle all information
+        that is required to serve your JSON response view.
+        """
+        try:
+            cache.set(self._get_cache_key(), {
+                'widget': self,
+                'url': self.get_url(),
+            })
+        except (PicklingError, cPicklingError, AttributeError):
+            msg = "You need to overwrite \"set_to_cache\" or ensure that %s is serialisable."
+            raise NotImplementedError(msg % self.__class__.__name__)
+
+    def render_options(self, *args):
         """Render only selected options."""
-        output = ['<option></option>' if not self.is_required else '']
-        choices = {(k, v) for k, v in choices if k in selected_choices}
+        try:
+            selected_choices, = args
+        except ValueError:  # Signature contained `choices` prior to Django 1.10
+            choices, selected_choices = args
+            choices = chain(self.choices, choices)
+        else:
+            choices = self.choices
+        output = ['<option value=""></option>' if not self.is_required and not self.allow_multiple_selected else '']
         selected_choices = {force_text(v) for v in selected_choices}
+        choices = [(k, v) for k, v in choices if force_text(k) in selected_choices]
         for option_value, option_label in choices:
             output.append(self.render_option(selected_choices, option_value, option_label))
         return '\n'.join(output)
 
 
-class HeavySelect2Widget(HeavySelect2Mixin, forms.Select):
-
+class HeavySelect2Widget(HeavySelect2Mixin, Select2Widget):
     """
     Select2 widget with AJAX support that registers itself to Django's Cache.
 
     Usage example::
 
-        class MyWidget(HeavySelectWidget):
+        class MyWidget(HeavySelect2Widget):
             data_view = 'my_view_name'
 
     or::
 
         class MyForm(forms.Form):
             my_field = forms.ChoicesField(
-                widget=HeavySelectWidget(
+                widget=HeavySelect2Widget(
                     data_url='/url/to/json/response'
                 )
             )
@@ -235,37 +306,29 @@ class HeavySelect2Widget(HeavySelect2Mixin, forms.Select):
     pass
 
 
-class HeavySelect2MultipleWidget(HeavySelect2Mixin, forms.SelectMultiple):
-
+class HeavySelect2MultipleWidget(HeavySelect2Mixin, Select2MultipleWidget):
     """Select2 multi select widget similar to :class:`.HeavySelect2Widget`."""
 
     pass
 
 
-class HeavySelect2TagWidget(HeavySelect2MultipleWidget):
+class HeavySelect2TagWidget(HeavySelect2Mixin, Select2TagWidget):
+    """Select2 tag widget."""
 
-    """Mixin to add select2 tag functionality."""
-
-    def build_attrs(self, extra_attrs=None, **kwargs):
-        """Add select2's tag attributes."""
-        self.attrs.setdefault('data-minimum-input-length', 1)
-        self.attrs.setdefault('data-tags', 'true')
-        self.attrs.setdefault('data-token-separators', [",", " "])
-        return super(HeavySelect2TagWidget, self).build_attrs(extra_attrs, **kwargs)
+    pass
 
 
 # Auto Heavy widgets
 
 
 class ModelSelect2Mixin(object):
-
     """Widget mixin that provides attributes and methods for :class:`.AutoResponseView`."""
 
     model = None
     queryset = None
     search_fields = []
     """
-    Model lookups that are used to filter the queryset.
+    Model lookups that are used to filter the QuerySet.
 
     Example::
 
@@ -282,14 +345,12 @@ class ModelSelect2Mixin(object):
         """
         Overwrite class parameters if passed as keyword arguments.
 
-        :param model: model to select choices from
-        :type model: django.db.models.Model
-        :param queryset: queryset to select choices from
-        :type queryset: django.db.models.query.QuerySet
-        :param search_fields: list of model lookup strings
-        :type search_fields: list
-        :param max_results: max. JsonResponse view page size
-        :type max_results: int
+        Args:
+            model (django.db.models.Model): Model to select choices from.
+            queryset (django.db.models.query.QuerySet): QuerySet to select choices from.
+            search_fields (list): List of model lookup strings.
+            max_results (int): Max. JsonResponse view page size.
+
         """
         self.model = kwargs.pop('model', self.model)
         self.queryset = kwargs.pop('queryset', self.queryset)
@@ -301,9 +362,9 @@ class ModelSelect2Mixin(object):
 
     def set_to_cache(self):
         """
-        Add widget's attributes to Djnago's cache.
+        Add widget's attributes to Django's cache.
 
-        Split the queryset, to not pickle the result set.
+        Split the QuerySet, to not pickle the result set.
         """
         queryset = self.get_queryset()
         cache.set(self._get_cache_key(), {
@@ -315,18 +376,26 @@ class ModelSelect2Mixin(object):
             'cls': self.__class__,
             'search_fields': self.search_fields,
             'max_results': self.max_results,
+            'url': self.get_url(),
+            'dependent_fields': self.dependent_fields,
         })
 
-    def filter_queryset(self, term, queryset=None):
+    def filter_queryset(self, term, queryset=None, **dependent_fields):
         """
-        Return queryset filtered by search_fields matching the passed term.
+        Return QuerySet filtered by search_fields matching the passed term.
+
+        Args:
+            term (str): Search term
+            queryset (django.db.models.query.QuerySet): QuerySet to select choices from.
+            **dependent_fields: Dependent fields and their values. If you want to inherit
+            from ModelSelect2Mixin and later call to this method, be sure to pop
+            from kwargs everything if it is not a dependent field.
+
+        Returns:
+            QuerySet: Filtered QuerySet
 
-        :param term: Search term
-        :type term: str
-        :return: Filtered queryset
-        :rtype: :class:`.django.db.models.QuerySet`
         """
-        if not queryset:
+        if queryset is None:
             queryset = self.get_queryset()
         search_fields = self.get_search_fields()
         select = Q()
@@ -335,14 +404,18 @@ class ModelSelect2Mixin(object):
         for t in [t for t in term.split(' ') if not t == '']:
             select &= reduce(lambda x, y: x | Q(**{y: t}), search_fields,
                              Q(**{search_fields[0]: t}))
+        if dependent_fields:
+            select &= Q(**dependent_fields)
+
         return queryset.filter(select).distinct()
 
     def get_queryset(self):
         """
-        Return queryset based on :attr:`.queryset` or :attr:`.model`.
+        Return QuerySet based on :attr:`.queryset` or :attr:`.model`.
+
+        Returns:
+            QuerySet: QuerySet of available choices.
 
-        :return: queryset of available choices
-        :rtype: :class:`.django.db.models.QuerySet`
         """
         if self.queryset is not None:
             queryset = self.queryset
@@ -364,26 +437,83 @@ class ModelSelect2Mixin(object):
             return self.search_fields
         raise NotImplementedError('%s, must implement "search_fields".' % self.__class__.__name__)
 
-    def render_options(self, choices, selected_choices):
-        """Render only selected options and set queryset from :class:`ModelChoicesIterator`."""
-        output = ['<option></option>' if not self.is_required else '']
+    def optgroups(self, name, value, attrs=None):
+        """Return only selected options and set QuerySet from `ModelChoicesIterator`."""
+        default = (None, [], 0)
+        groups = [default]
+        has_selected = False
+        selected_choices = {force_text(v) for v in value}
+        if not self.is_required and not self.allow_multiple_selected:
+            default[1].append(self.create_option(name, '', '', False, 0))
+        if not isinstance(self.choices, ModelChoiceIterator):
+            return super(ModelSelect2Mixin, self).optgroups(name, value, attrs=attrs)
+        selected_choices = {
+            c for c in selected_choices
+            if c not in self.choices.field.empty_values
+        }
+        choices = (
+            (obj.pk, self.label_from_instance(obj))
+            for obj in self.choices.queryset.filter(pk__in=selected_choices)
+        )
+        for option_value, option_label in choices:
+            selected = (
+                force_text(option_value) in value and
+                (has_selected is False or self.allow_multiple_selected)
+            )
+            if selected is True and has_selected is False:
+                has_selected = True
+            index = len(default[1])
+            subgroup = default[1]
+            subgroup.append(self.create_option(name, option_value, option_label, selected_choices, index))
+        return groups
+
+    def render_options(self, *args):
+        """Render only selected options and set QuerySet from :class:`ModelChoiceIterator`."""
+        try:
+            selected_choices, = args
+        except ValueError:
+            choices, selected_choices = args
+            choices = chain(self.choices, choices)
+        else:
+            choices = self.choices
+        selected_choices = {force_text(v) for v in selected_choices}
+        output = ['<option value=""></option>' if not self.is_required and not self.allow_multiple_selected else '']
         if isinstance(self.choices, ModelChoiceIterator):
-            if not self.queryset:
+            if self.queryset is None:
                 self.queryset = self.choices.queryset
             selected_choices = {c for c in selected_choices
                                 if c not in self.choices.field.empty_values}
-            choices = {self.choices.choice(obj)
-                       for obj in self.choices.queryset.filter(pk__in=selected_choices)}
+            choices = [(obj.pk, self.label_from_instance(obj))
+                       for obj in self.choices.queryset.filter(pk__in=selected_choices)]
         else:
-            choices = {(k, v) for k, v in choices if k in selected_choices}
-        selected_choices = {force_text(v) for v in selected_choices}
+            choices = [(k, v) for k, v in choices if force_text(k) in selected_choices]
         for option_value, option_label in choices:
             output.append(self.render_option(selected_choices, option_value, option_label))
         return '\n'.join(output)
 
+    def label_from_instance(self, obj):
+        """
+        Return option label representation from instance.
+
+        Can be overridden to change the representation of each choice.
+
+        Example usage::
+
+            class MyWidget(ModelSelect2Widget):
+                def label_from_instance(obj):
+                    return force_text(obj.title).upper()
+
+        Args:
+            obj (django.db.models.Model): Instance of Django Model.
+
+        Returns:
+            str: Option label.
+
+        """
+        return force_text(obj)
+
 
 class ModelSelect2Widget(ModelSelect2Mixin, HeavySelect2Widget):
-
     """
     Select2 drop in model select widget.
 
@@ -391,7 +521,7 @@ class ModelSelect2Widget(ModelSelect2Mixin, HeavySelect2Widget):
 
         class MyWidget(ModelSelect2Widget):
             search_fields = [
-                'title__icontians',
+                'title__icontains',
             ]
 
         class MyModelForm(forms.ModelForm):
@@ -413,8 +543,8 @@ class ModelSelect2Widget(ModelSelect2Mixin, HeavySelect2Widget):
             )
 
     .. tip:: The ModelSelect2(Multiple)Widget will try
-        to get the queryset from the fields choices.
-        Therefore you don't need to define a queryset,
+        to get the QuerySet from the fields choices.
+        Therefore you don't need to define a QuerySet,
         if you just drop in the widget for a ForeignKey field.
     """
 
@@ -422,7 +552,6 @@ class ModelSelect2Widget(ModelSelect2Mixin, HeavySelect2Widget):
 
 
 class ModelSelect2MultipleWidget(ModelSelect2Mixin, HeavySelect2MultipleWidget):
-
     """
     Select2 drop in model multiple select widget.
 
@@ -433,13 +562,12 @@ class ModelSelect2MultipleWidget(ModelSelect2Mixin, HeavySelect2MultipleWidget):
 
 
 class ModelSelect2TagWidget(ModelSelect2Mixin, HeavySelect2TagWidget):
-
     """
-    Select2 model field with tag support.
+    Select2 model widget with tag support.
 
     This it not a simple drop in widget.
     It requires to implement you own :func:`.value_from_datadict`
-    that adds missing tags to you queryset.
+    that adds missing tags to you QuerySet.
 
     Example::
 
@@ -447,7 +575,7 @@ class ModelSelect2TagWidget(ModelSelect2Mixin, HeavySelect2TagWidget):
             queryset = MyModel.objects.all()
 
             def value_from_datadict(self, data, files, name):
-                values = super().value_from_datadict(self, data, files, name):
+                values = super().value_from_datadict(self, data, files, name)
                 qs = self.queryset.filter(**{'pk__in': list(values)})
                 pks = set(force_text(getattr(o, pk)) for o in qs)
                 cleaned_values = []

django_select2/static/django_select2/django_select2.js

@@ -1,26 +1,56 @@
-$(function () {
-    $('.django-select2').not('django-select2-heavy').select2();
-    $('.django-select2.django-select2-heavy').each(function () {
-        var field_id = $(this).data('field_id');
-        $(this).select2({
-            ajax: {
-                data: function (params) {
-                    return {
-                        term: params.term,
-                        page: params.page,
-                        field_id: field_id
-                    }
-                },
-                processResults: function (data, page) {
-                    return {
-                        results: data.results,
-                        pagination: {
-                            more: data.more
-                        }
-                  }
-                }
-            }
-        });
-    });
-});
+(function ($) {
+  var init = function ($element, options) {
+    $element.select2(options)
+  }
 
+  var initHeavy = function ($element, options) {
+    var settings = $.extend({
+      ajax: {
+        data: function (params) {
+          var result = {
+            term: params.term,
+            page: params.page,
+            field_id: $element.data('field_id')
+          }
+
+          var dependentFields = $element.data('select2-dependent-fields')
+          if (dependentFields) {
+            dependentFields = dependentFields.trim().split(/\s+/)
+            $.each(dependentFields, function (i, dependentField) {
+              result[dependentField] = $('[name=' + dependentField + ']', $element.closest('form')).val()
+            })
+          }
+
+          return result
+        },
+        processResults: function (data, page) {
+          return {
+            results: data.results,
+            pagination: {
+              more: data.more
+            }
+          }
+        }
+      }
+    }, options)
+
+    $element.select2(settings)
+  }
+
+  $.fn.djangoSelect2 = function (options) {
+    var settings = $.extend({}, options)
+    $.each(this, function (i, element) {
+      var $element = $(element)
+      if ($element.hasClass('django-select2-heavy')) {
+        initHeavy($element, settings)
+      } else {
+        init($element, settings)
+      }
+    })
+    return this
+  }
+
+  $(function () {
+    $('.django-select2').djangoSelect2()
+  })
+}(this.jQuery))

django_select2/urls.py

@@ -1,20 +1,19 @@
 # -*- coding: utf-8 -*-
 """
-Django-Select2 url config.
+Django-Select2 URL configuration.
 
-Add `django_select` to your urlconf **if** you use any 'Model' fields::
+Add `django_select` to your ``urlconf`` **if** you use any 'Model' fields::
 
     url(r'^select2/', include('django_select2.urls')),
 
 """
 from __future__ import absolute_import, unicode_literals
 
-from django.conf.urls import patterns, url
+from django.conf.urls import url
 
 from .views import AutoResponseView
 
-urlpatterns = patterns(
-    "",
+urlpatterns = [
     url(r"^fields/auto.json$",
         AutoResponseView.as_view(), name="django_select2-json"),
-)
+]

django_select2/views.py

@@ -5,7 +5,6 @@ from __future__ import absolute_import, unicode_literals
 from django.core import signing
 from django.core.signing import BadSignature
 from django.http import Http404, JsonResponse
-from django.utils.encoding import smart_text
 from django.views.generic.list import BaseListView
 
 from .cache import cache
@@ -13,7 +12,6 @@ from .conf import settings
 
 
 class AutoResponseView(BaseListView):
-
     """
     View that handles requests from heavy model widgets.
 
@@ -44,7 +42,7 @@ class AutoResponseView(BaseListView):
         return JsonResponse({
             'results': [
                 {
-                    'text': smart_text(obj),
+                    'text': self.widget.label_from_instance(obj),
                     'id': obj.pk,
                 }
                 for obj in context['object_list']
@@ -53,8 +51,13 @@ class AutoResponseView(BaseListView):
         })
 
     def get_queryset(self):
-        """Get queryset from cached widget."""
-        return self.widget.filter_queryset(self.term, self.queryset)
+        """Get QuerySet from cached widget."""
+        kwargs = {
+            model_field_name: self.request.GET.get(form_field_name)
+            for form_field_name, model_field_name in self.widget.dependent_fields.items()
+            if form_field_name in self.request.GET and self.request.GET.get(form_field_name, '') != ''
+        }
+        return self.widget.filter_queryset(self.term, self.queryset, **kwargs)
 
     def get_paginate_by(self, queryset):
         """Paginate response by size of widget's `max_results` parameter."""
@@ -64,10 +67,12 @@ class AutoResponseView(BaseListView):
         """
         Get and return widget from cache.
 
-        Raises a 404 if the widget can not be found or no id is provided.
+        Raises:
+            Http404: If if the widget can not be found or no id is provided.
+
+        Returns:
+            ModelSelect2Mixin: Widget from cache.
 
-        :raises: Http404
-        :return: ModelSelect2Mixin
         """
         field_id = self.kwargs.get('field_id', self.request.GET.get('field_id', None))
         if not field_id:
@@ -81,6 +86,8 @@ class AutoResponseView(BaseListView):
             widget_dict = cache.get(cache_key)
             if widget_dict is None:
                 raise Http404('field_id not found')
+            if widget_dict.pop('url') != self.request.path:
+                raise Http404('field_id was issued for the view.')
         qs, qs.query = widget_dict.pop('queryset')
         self.queryset = qs.all()
         widget_dict['queryset'] = self.queryset

docs/Makefile

@@ -46,6 +46,11 @@ html:
 	@echo
 	@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."
 
+spelling:
+	$(SPHINXBUILD) -b spelling -W $(ALLSPHINXOPTS) $(BUILDDIR)/spelling
+	@echo
+	@echo "Spell check finished. The results are in $(BUILDDIR)/spelling."
+
 dirhtml:
 	$(SPHINXBUILD) -b dirhtml $(ALLSPHINXOPTS) $(BUILDDIR)/dirhtml
 	@echo

docs/conf.py

@@ -41,7 +41,14 @@ sys.path.insert(0, os.path.abspath('..'))
 
 # Add any Sphinx extension module names here, as strings. They can be extensions
 # coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
-extensions = ['sphinx.ext.autodoc',  'sphinx.ext.inheritance_diagram', 'sphinx.ext.intersphinx', 'sphinx.ext.viewcode']
+extensions = [
+    'sphinx.ext.autodoc',
+    'sphinx.ext.napoleon',
+    'sphinx.ext.inheritance_diagram',
+    'sphinx.ext.intersphinx',
+    'sphinx.ext.viewcode',
+    'sphinxcontrib.spelling',
+]
 
 intersphinx_mapping = {
     'python': ('http://docs.python.org/3.5', None),
@@ -49,6 +56,11 @@ intersphinx_mapping = {
                'https://docs.djangoproject.com/en/dev/_objects/'),
 }
 
+# spell check
+spelling_word_list_filename = 'spelling_wordlist.txt'
+spelling_show_suggestions = True
+
+
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']
 

docs/django_select2.rst

@@ -40,3 +40,47 @@ Cache
     :members:
     :undoc-members:
     :show-inheritance:
+
+
+JavaScript
+----------
+
+DjangoSelect2 handles the initialization of select2 fields automatically. Just include
+``{{ form.media.js }}`` in your template before the closing ``body`` tag. That's it!
+
+If you insert forms after page load or if you want to handle the initialization
+yourself, DjangoSelect2 provides a jQuery plugin. It will handle both normal and
+heavy fields. Simply call ``djangoSelect2(options)`` on your select fields.::
+
+        $('.django-select2').djangoSelect2();
+
+
+You can pass see `Select2 options <https://select2.github.io/options.html>`_ if needed::
+
+        $('.django-select2').djangoSelect2({placeholder: 'Select an option'});
+
+Security & Authentication
+-------------------------
+
+Security is important. Therefore make sure to read and understand what
+the security measures in place and their limitations.
+
+Set up a separate cache. If you have a public form that uses a model widget
+make sure to setup a separate cache database for Select2. An attacker
+could constantly reload your site and fill up the select2 cache.
+Having a separate cache allows you to limit the effect to select2 only.
+
+You might want to add a secure select2 JSON endpoint for data you don't
+want to be accessible to the general public. Doing so is easy::
+
+    class UserSelect2View(LoginRequiredMixin, AutoResponseView):
+        pass
+
+    class UserSelect2WidgetMixin(object):
+        def __init__(self, *args, **kwargs):
+            kwargs['data_view'] = 'user-select2-view'
+            super(UserSelect2WidgetMixin, self).__init__(*args, **kwargs)
+
+    class MySecretWidget(UserSelect2WidgetMixin, Select2ModelWidget):
+        model = MySecretModel
+        search_fields = ['title__icontains']

docs/external_req.txt

@@ -1 +1,3 @@
-Django >= 1.4.1
+Django >= 1.8
+sphinxcontrib-spelling
+pyenchant

docs/extra.rst

@@ -0,0 +1,119 @@
+Extra
+=====
+
+Chained select2
+---------------
+
+Suppose you have an address form where a user should choose a Country and a City.
+When the user selects a country we want to show only cities belonging to that country.
+So the one selector depends on another one.
+
+Models
+``````
+
+Here are our two models:
+
+.. code-block:: python
+
+    class Country(models.Model):
+        name = models.CharField(max_length=255)
+
+
+    class City(models.Model):
+        name = models.CharField(max_length=255)
+        country = models.ForeignKey('Country', related_name="cities")
+
+
+Customizing a Form
+``````````````````
+
+Lets link two widgets via *dependent_fields*.
+
+.. code-block:: python
+    :emphasize-lines: 15
+
+    class AddressForm(forms.Form):
+        country = forms.ModelChoiceField(
+            queryset=Country.objects.all(),
+            label=u"Country",
+            widget=ModelSelect2Widget(
+                search_fields=['name__icontains'],
+            )
+        )
+
+        city = forms.ModelChoiceField(
+            queryset=City.objects.all(),
+            label=u"City",
+            widget=ModelSelect2Widget(
+                search_fields=['name__icontains'],
+                dependent_fields={'country': 'country'},
+                max_results=500,
+            )
+        )
+
+
+Interdependent select2
+----------------------
+
+Also you may want not to restrict the user to which field should be selected first.
+Instead you want to suggest to the user options for any select2 depending of his selection in another one.
+
+Customize the form in a manner:
+
+.. code-block:: python
+    :emphasize-lines: 7
+
+    class AddressForm(forms.Form):
+        country = forms.ModelChoiceField(
+            queryset=Country.objects.all(),
+            label=u"Country",
+            widget=ModelSelect2Widget(
+                search_fields=['name__icontains'],
+                dependent_fields={'city': 'cities'},
+            )
+        )
+
+        city = forms.ModelChoiceField(
+            queryset=City.objects.all(),
+            label=u"City",
+            widget=ModelSelect2Widget(
+                search_fields=['name__icontains'],
+                dependent_fields={'country': 'country'},
+                max_results=500,
+            )
+        )
+
+Take attention to country's dependent_fields. The value of 'city' is 'cities' because of
+related name used in a filter condition `cities` which differs from widget field name `city`.
+
+.. caution::
+    Be aware of using interdependent select2 in parent-child relation.
+    When a child is selected, you are restricted to change parent (only one value is available).
+    Probably you should let the user reset the child first to release parent select2.
+
+
+Multi-dependent select2
+-----------------------
+
+Furthermore you may want to filter options on two or more select2 selections (some code is dropped for clarity):
+
+.. code-block:: python
+    :emphasize-lines: 14
+
+    class SomeForm(forms.Form):
+        field1 = forms.ModelChoiceField(
+            widget=ModelSelect2Widget(
+            )
+        )
+
+        field2 = forms.ModelChoiceField(
+            widget=ModelSelect2Widget(
+            )
+        )
+
+        field3 = forms.ModelChoiceField(
+            widget=ModelSelect2Widget(
+                dependent_fields={'field1': 'field1', 'field2': 'field2'},
+            )
+        )
+

docs/get_started.rst

@@ -18,7 +18,8 @@ Installation
 2. Add ``django_select2`` to your ``INSTALLED_APPS`` in your project settings.
 
 
-3. Add ``django_select`` to your urlconf **if** you use any 'Auto' fields::
+3. Add ``django_select`` to your ``urlconf`` **if** you use any
+:class:`ModelWidgets <.django_select2.forms.ModelSelect2Mixin>`::
 
         url(r'^select2/', include('django_select2.urls')),
 

docs/index.rst

@@ -14,6 +14,7 @@ Contents:
 
    get_started
    django_select2
+   extra
 
 Indices and tables
 ==================

docs/spelling_wordlist.txt

@@ -0,0 +1,18 @@
+jQuery
+Django
+mixin
+backend
+redis
+memcached
+AJAX
+Cloudflare
+lookup
+QuerySet
+pre
+py
+lookups
+functionalities
+plugin
+multi
+Indices
+clearable

requirements-dev.in

@@ -0,0 +1,14 @@
+coverage
+django-appconf
+flake8
+pep8-naming
+mccabe
+isort
+pydocstyle
+pytest
+pytest-django
+selenium
+sphinx
+sphinxcontrib-spelling
+pyenchant
+django-redis

requirements-dev.txt

@@ -0,0 +1,34 @@
+#
+# This file is autogenerated by pip-compile
+# To update, run:
+#
+#    pip-compile --output-file requirements-dev.txt requirements-dev.in
+#
+alabaster==0.7.10 # via sphinx
+babel==2.4.0 # via sphinx
+coverage==4.3.4
+django-appconf==1.0.2
+django-redis==4.7.0
+docutils==0.13.1 # via sphinx
+flake8==3.3.0
+isort==4.2.5
+jinja2==2.9.6 # via sphinx
+markupsafe==1.0          # via jinja2
+mccabe==0.6.1
+pydocstyle==1.1.1
+pep8-naming==0.4.1
+pep8==1.7.0               # via flake8
+py==1.4.33 # via pytest
+pyenchant==1.6.8
+pyflakes==1.5.0 # via flake8
+pygments==2.2.0 # via sphinx
+pytest-django==3.1.2
+pytest==3.0.7
+pytz==2017.2 # via babel
+redis==2.10.5             # via django-redis
+selenium==3.3.3
+six==1.10.0               # via django-appconf, sphinx, sphinxcontrib-spelling
+snowballstemmer==1.2.1    # via sphinx
+sphinx-rtd-theme==0.2.4   # via sphinx
+sphinx==1.5.5
+sphinxcontrib-spelling==2.3.0

requirements_dev.txt

@@ -1,19 +0,0 @@
--e .
-django-appconf==1.0.1
-django==1.8.4             # via model-mommy
-flake8==2.4.1
-isort==4.2.2
-mccabe==0.3.1             # via flake8
-mock==1.3.0               # via model-mommy
-model-mommy==1.2.5
-pbr==1.8.0                # via mock
-pep257==0.5.0
-pep8-naming==0.3.3
-pep8==1.5.7               # via flake8
-py==1.4.30                # via pytest
-pyflakes==0.8.1           # via flake8
-pytest-django==2.8.0
-pytest==2.7.2
-requests==2.7.0
-selenium==2.46.0
-six==1.9.0                # via django-appconf, mock, model-mommy

setup.cfg

@@ -1,5 +1,5 @@
-[pytest]
-norecursedirs = env
+[tool:pytest]
+norecursedirs = env docs
 addopts = --tb=short -rxs
 DJANGO_SETTINGS_MODULE=tests.testapp.settings
 
@@ -8,16 +8,17 @@ max-line-length = 120
 max-complexity = 10
 statistics = true
 show-source = true
-exclude = docs,runtests.py,setup.py,env
+exclude = docs,runtests.py,setup.py,.tox,env
 
 [pep257]
-explain = true
-count = true
+match = (?!setup).*.py
+match-dir = (?!tests|env|docs|\.).*
 
 [isort]
 atomic = true
 multi_line_output = 5
 line_length = 79
-skip = manage.py,docs
-known_first_party = django_select2
+skip = manage.py,docs,.tox,env
+known_first_party = django_select2, tests
+known_third_party = django
 combine_as_imports = true

setup.py

@@ -22,23 +22,6 @@ URL = "https://github.com/applegrew/django-select2"
 VERSION = __import__(PACKAGE).__version__
 
 
-class PyTest(Command):
-    user_options = []
-
-    def initialize_options(self):
-        pass
-
-    def finalize_options(self):
-        pass
-
-    def run(self):
-        import sys
-        import subprocess
-
-        errno = subprocess.call([sys.executable, 'runtests.py'])
-        raise SystemExit(errno)
-
-
 setup(
     name=NAME,
     version=VERSION,
@@ -59,13 +42,13 @@ setup(
         "Programming Language :: Python",
         "Programming Language :: Python :: 2",
         "Programming Language :: Python :: 3",
-        "Framework :: Django :: 1.7",
-        "Framework :: Django :: 1.8",
         "Framework :: Django",
+        "Framework :: Django :: 1.8",
+        "Framework :: Django :: 1.10",
+        "Framework :: Django :: 1.11",
     ],
     install_requires=[
         'django-appconf>=0.6.0',
     ],
     zip_safe=False,
-    cmdclass={'test': PyTest},
 )

tests/conftest.py

@@ -2,21 +2,35 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 import os
+import random
+import string
+from time import sleep
 
 import pytest
-from model_mommy import mommy
+from django.utils.encoding import force_text
 from selenium import webdriver
 from selenium.common.exceptions import WebDriverException
 
 browsers = {
-    # 'firefox': webdriver.Firefox,
-    # 'chrome': webdriver.Chrome,
+    'chrome': webdriver.Chrome,
+    'firefox': webdriver.Firefox,
     'phantomjs': webdriver.PhantomJS,
 }
 
 
-@pytest.fixture(scope='session',
-                params=browsers.keys())
+def random_string(n):
+    return ''.join(
+        random.choice(string.ascii_uppercase + string.digits)
+        for _ in range(n)
+    )
+
+
+def random_name(n):
+    words = ''.join(random.choice(string.ascii_lowercase + ' ') for _ in range(n)).strip().split(' ')
+    return '-'.join([x.capitalize() for x in words])
+
+
+@pytest.yield_fixture(scope='session', params=sorted(browsers.keys()))
 def driver(request):
     if 'DISPLAY' not in os.environ:
         pytest.skip('Test requires display server (export DISPLAY)')
@@ -24,18 +38,44 @@ def driver(request):
     try:
         b = browsers[request.param]()
     except WebDriverException as e:
-        pytest.skip(e)
+        pytest.skip(force_text(e))
     else:
         b.set_window_size(1200, 800)
-        request.addfinalizer(lambda *args: b.quit())
-        return b
+        yield b
+        if request.param == 'chrome':
+            # chrome needs a couple of seconds before it can be quit
+            sleep(5)
+        b.quit()
 
 
 @pytest.fixture
 def genres(db):
-    return mommy.make('testapp.Genre', _quantity=100)
+    from .testapp.models import Genre
+
+    return Genre.objects.bulk_create(
+        [Genre(pk=pk, title=random_string(50)) for pk in range(100)]
+    )
 
 
 @pytest.fixture
 def artists(db):
-    return mommy.make('testapp.Artist', _quantity=100)
+    from .testapp.models import Artist
+    return Artist.objects.bulk_create(
+        [Artist(pk=pk, title=random_string(50)) for pk in range(100)]
+    )
+
+
+@pytest.fixture
+def countries(db):
+    from .testapp.models import Country
+    return Country.objects.bulk_create(
+        [Country(pk=pk, name=random_name(random.randint(10, 20))) for pk in range(10)]
+    )
+
+
+@pytest.fixture
+def cities(db, countries):
+    from .testapp.models import City
+    return City.objects.bulk_create(
+        [City(pk=pk, name=random_name(random.randint(5, 15)), country=random.choice(countries)) for pk in range(100)]
+    )

tests/test_forms.py

@@ -6,30 +6,42 @@ import json
 
 import pytest
 from django.core import signing
-from django.core.urlresolvers import reverse
 from django.db.models import QuerySet
 from django.utils.encoding import force_text
-from model_mommy import mommy
+from django.utils.six import text_type
 from selenium.common.exceptions import NoSuchElementException
-from six import text_type
+from selenium.webdriver.common.by import By
+from selenium.webdriver.support import expected_conditions
+from selenium.webdriver.support.wait import WebDriverWait
 
 from django_select2.cache import cache
 from django_select2.forms import (
-    HeavySelect2Widget, ModelSelect2TagWidget, ModelSelect2Widget,
-    Select2Widget
+    HeavySelect2MultipleWidget, HeavySelect2Widget, ModelSelect2TagWidget,
+    ModelSelect2Widget, Select2Widget
 )
 from tests.testapp import forms
 from tests.testapp.forms import (
     NUMBER_CHOICES, HeavySelect2MultipleWidgetForm, TitleModelSelect2Widget
 )
-from tests.testapp.models import Genre
+from tests.testapp.models import City, Country, Genre
+
+try:
+    from django.urls import reverse
+except ImportError:
+    from django.core.urlresolvers import reverse
 
 
 class TestSelect2Mixin(object):
     url = reverse('select2_widget')
     form = forms.AlbumSelect2WidgetForm()
+    multiple_form = forms.AlbumSelect2MultipleWidgetForm()
     widget_cls = Select2Widget
 
+    def test_initial_data(self, genres):
+        genre = genres[0]
+        form = self.form.__class__(initial={'primary_genre': genre.pk})
+        assert text_type(genre) in form.as_p()
+
     def test_initial_form_class(self):
         widget = self.widget_cls(attrs={'class': 'my-class'})
         assert 'my-class' in widget.render('name', None)
@@ -40,7 +52,7 @@ class TestSelect2Mixin(object):
         assert required_field.required is True
         assert 'data-allow-clear="true"' not in required_field.widget.render('artist', None)
         assert 'data-allow-clear="false"' in required_field.widget.render('artist', None)
-        assert '<option></option>' not in required_field.widget.render('artist', None)
+        assert '<option value=""></option>' not in required_field.widget.render('artist', None)
 
         not_required_field = self.form.fields['primary_genre']
         assert not_required_field.required is False
@@ -48,7 +60,7 @@ class TestSelect2Mixin(object):
         assert 'data-allow-clear="false"' not in not_required_field.widget.render('primary_genre',
                                                                                   None)
         assert 'data-placeholder' in not_required_field.widget.render('primary_genre', None)
-        assert '<option></option>' in not_required_field.widget.render('primary_genre', None)
+        assert '<option value=""></option>' in not_required_field.widget.render('primary_genre', None)
 
     def test_no_js_error(self, db, live_server, driver):
         driver.get(live_server + self.url)
@@ -78,14 +90,51 @@ class TestSelect2Mixin(object):
         widget = HeavySelect2Widget(data_url='/foo/bar')
         assert widget.get_url() == '/foo/bar'
 
+    def test_empty_option(self, db):
+        # Empty options is only required for single selects
+        # https://select2.github.io/options.html#allowClear
+        single_select = self.form.fields['primary_genre']
+        assert single_select.required is False
+        assert '<option value=""></option>' in single_select.widget.render('primary_genre', None)
+
+        multiple_select = self.multiple_form.fields['featured_artists']
+        assert multiple_select.required is False
+        assert multiple_select.widget.allow_multiple_selected
+        assert '<option value=""></option>' not in multiple_select.widget.render('featured_artists', None)
+
+
+class TestSelect2MixinSettings(object):
+    def test_default_media(self):
+        sut = Select2Widget()
+        result = sut.media.render()
+        assert '//cdnjs.cloudflare.com/ajax/libs/select2/4.0.3/js/select2.min.js' in result
+        assert '//cdnjs.cloudflare.com/ajax/libs/select2/4.0.3/css/select2.min.css' in result
+        assert 'django_select2/django_select2.js' in result
+
+    def test_js_setting(self, settings):
+        settings.SELECT2_JS = 'alternate.js'
+        sut = Select2Widget()
+        result = sut.media.render()
+        assert 'alternate.js' in result
+        assert 'django_select2/django_select2.js' in result
+
+    def test_css_setting(self, settings):
+        settings.SELECT2_CSS = 'alternate.css'
+        sut = Select2Widget()
+        result = sut.media.render()
+        assert 'alternate.css' in result
+
 
 class TestHeavySelect2Mixin(TestSelect2Mixin):
     url = reverse('heavy_select2_widget')
-    form = forms.HeavySelect2WidgetForm(initial={'primary_genre': [1]})
+    form = forms.HeavySelect2WidgetForm(initial={'primary_genre': 1})
     widget_cls = HeavySelect2Widget
 
+    def test_initial_data(self):
+        assert 'One' in self.form.as_p()
+
     def test_initial_form_class(self):
-        widget = self.widget_cls(data_view='heavy_data', attrs={'class': 'my-class'})
+        widget = self.widget_cls(data_view='heavy_data_1', attrs={'class': 'my-class'})
         assert 'my-class' in widget.render('name', None)
         assert 'django-select2' in widget.render('name', None)
         assert 'django-select2-heavy' in widget.render('name', None), widget.render('name', None)
@@ -94,27 +143,81 @@ class TestHeavySelect2Mixin(TestSelect2Mixin):
         not_required_field = self.form.fields['primary_genre']
         assert not_required_field.required is False
         assert '<option value="1" selected="selected">One</option>' in \
-               not_required_field.widget.render('primary_genre', 1, choices=NUMBER_CHOICES), \
-            not_required_field.widget.render('primary_genre', 1, choices=NUMBER_CHOICES)
+               not_required_field.widget.render('primary_genre', 1) or \
+            '<option value="1" selected>One</option>' in \
+            not_required_field.widget.render('primary_genre', 1), \
+            not_required_field.widget.render('primary_genre', 1)
 
     def test_many_selected_option(self, db, genres):
         field = HeavySelect2MultipleWidgetForm().fields['genres']
-        widget_output = field.widget.render(
-            'genres', [1, 2],
-            choices=NUMBER_CHOICES)
+        field.widget.choices = NUMBER_CHOICES
+        widget_output = field.widget.render('genres', [1, 2])
         selected_option = '<option value="{pk}" selected="selected">{value}</option>'.format(pk=1, value='One')
+        selected_option_a = '<option value="{pk}" selected>{value}</option>'.format(pk=1, value='One')
         selected_option2 = '<option value="{pk}" selected="selected">{value}</option>'.format(pk=2, value='Two')
+        selected_option2a = '<option value="{pk}" selected>{value}</option>'.format(pk=2, value='Two')
 
-        assert selected_option in widget_output, widget_output
-        assert selected_option2 in widget_output
+        assert selected_option in widget_output or selected_option_a in widget_output, widget_output
+        assert selected_option2 in widget_output or selected_option2a in widget_output
+
+    def test_multiple_widgets(self, db, live_server, driver):
+        driver.get(live_server + self.url)
+        with pytest.raises(NoSuchElementException):
+            driver.find_element_by_css_selector('.select2-results')
+
+        elem1, elem2 = driver.find_elements_by_css_selector('.select2-selection')
+        elem1.click()
+
+        result1 = WebDriverWait(driver, 60).until(
+            expected_conditions.presence_of_element_located((By.CSS_SELECTOR, '.select2-results li:first-child'))
+        ).text
+        elem2.click()
+        result2 = WebDriverWait(driver, 60).until(
+            expected_conditions.presence_of_element_located((By.CSS_SELECTOR, '.select2-results li:first-child'))
+        ).text
+
+        assert result1 != result2
+
+        with pytest.raises(NoSuchElementException):
+            error = driver.find_element_by_xpath('//body[@JSError]')
+            pytest.fail(error.get_attribute('JSError'))
+
+    def test_get_url(self):
+        widget = self.widget_cls(data_view='heavy_data_1', attrs={'class': 'my-class'})
+        assert isinstance(widget.get_url(), text_type)
+
+    def test_can_not_pickle(self):
+        widget = self.widget_cls(data_view='heavy_data_1', attrs={'class': 'my-class'})
+
+        class NoPickle(object):
+            pass
+
+        widget.no_pickle = NoPickle()
+        with pytest.raises(NotImplementedError):
+            widget.set_to_cache()
 
 
 class TestModelSelect2Mixin(TestHeavySelect2Mixin):
     form = forms.AlbumModelSelect2WidgetForm(initial={'primary_genre': 1})
+    multiple_form = forms.ArtistModelSelect2MultipleWidgetForm()
+
+    def test_initial_data(self, genres):
+        genre = genres[0]
+        form = self.form.__class__(initial={'primary_genre': genre.pk})
+        assert text_type(genre) in form.as_p()
+
+    def test_label_from_instance_initial(self, genres):
+        genre = genres[0]
+        genre.title = genre.title.lower()
+        genre.save()
+
+        form = self.form.__class__(initial={'primary_genre': genre.pk})
+        assert genre.title not in form.as_p(), form.as_p()
+        assert genre.title.upper() in form.as_p()
 
     @pytest.fixture(autouse=True)
-    def genres(self, db):
-        return mommy.make(Genre, 100)
+    def genres(self, genres):
+        return genres
 
     def test_selected_option(self, db, genres):
         genre = genres[0]
@@ -125,12 +228,32 @@ class TestModelSelect2Mixin(TestHeavySelect2Mixin):
             'primary_genre', genre.pk)
         selected_option = '<option value="{pk}" selected="selected">{value}</option>'.format(
             pk=genre.pk, value=force_text(genre))
+        selected_option_a = '<option value="{pk}" selected>{value}</option>'.format(
+            pk=genre.pk, value=force_text(genre))
         unselected_option = '<option value="{pk}">{value}</option>'.format(
             pk=genre2.pk, value=force_text(genre2))
 
-        assert selected_option in widget_output, widget_output
+        assert selected_option in widget_output or selected_option_a in widget_output, widget_output
         assert unselected_option not in widget_output
 
+    def test_selected_option_label_from_instance(self, db, genres):
+        genre = genres[0]
+        genre.title = genre.title.lower()
+        genre.save()
+
+        field = self.form.fields['primary_genre']
+        widget_output = field.widget.render('primary_genre', genre.pk)
+
+        def get_selected_options(genre):
+            return '<option value="{pk}" selected="selected">{value}</option>'.format(
+                pk=genre.pk, value=force_text(genre)), '<option value="{pk}" selected>{value}</option>'.format(
+                pk=genre.pk, value=force_text(genre))
+
+        assert all(o not in widget_output for o in get_selected_options(genre))
+        genre.title = genre.title.upper()
+
+        assert any(o in widget_output for o in get_selected_options(genre))
+
     def test_get_queryset(self):
         widget = ModelSelect2Widget()
         with pytest.raises(NotImplementedError):
@@ -192,6 +315,10 @@ class TestModelSelect2Mixin(TestHeavySelect2Mixin):
         assert isinstance(cached_widget['queryset'][0], qs.__class__)
         assert text_type(cached_widget['queryset'][1]) == text_type(qs.query)
 
+    def test_get_url(self):
+        widget = ModelSelect2Widget(queryset=Genre.objects.all(), search_fields=['title__icontains'])
+        assert isinstance(widget.get_url(), text_type)
+
 
 class TestHeavySelect2TagWidget(TestHeavySelect2Mixin):
 
@@ -207,3 +334,90 @@ class TestHeavySelect2TagWidget(TestHeavySelect2Mixin):
             queryset=Genre.objects.all(), search_fields=['title__icontains'], attrs={'data-minimum-input-length': '3'})
         output = widget.render('name', 'value')
         assert 'data-minimum-input-length="3"' in output
+
+
+class TestHeavySelect2MultipleWidget(object):
+    url = reverse('heavy_select2_multiple_widget')
+    form = forms.HeavySelect2MultipleWidgetForm()
+    widget_cls = HeavySelect2MultipleWidget
+
+    def test_widgets_selected_after_validation_error(self, db, live_server, driver):
+        driver.get(live_server + self.url)
+        title = driver.find_element_by_id('id_title')
+        title.send_keys('fo')
+        genres, fartists = driver.find_elements_by_css_selector('.select2-selection--multiple')
+        genres.click()
+        genres.send_keys('o')  # results are Zero One Two Four
+        # select second element - One
+        driver.find_element_by_css_selector('.select2-results li:nth-child(2)').click()
+        genres.submit()
+        # there is a ValidationError raised, check for it
+        errstring = WebDriverWait(driver, 10).until(
+            expected_conditions.presence_of_element_located((By.CSS_SELECTOR, 'ul.errorlist li'))
+        ).text
+        assert errstring == "Title must have more than 3 characters."
+        # genres should still have One as selected option
+        result_title = driver.find_element_by_css_selector('.select2-selection--multiple li').get_attribute('title')
+        assert result_title == 'One'
+
+
+class TestAddressChainedSelect2Widget(object):
+    url = reverse('model_chained_select2_widget')
+    form = forms.AddressChainedSelect2WidgetForm()
+
+    def test_widgets_selected_after_validation_error(self, db, live_server, driver, countries, cities):
+        driver.get(live_server + self.url)
+
+        WebDriverWait(driver, 60).until(
+            expected_conditions.presence_of_element_located((By.CSS_SELECTOR, '.select2-selection--single'))
+        )
+        country_container, city_container = driver.find_elements_by_css_selector('.select2-selection--single')
+
+        # clicking city select2 lists all available cities
+        city_container.click()
+        WebDriverWait(driver, 60).until(
+            expected_conditions.presence_of_element_located((By.CSS_SELECTOR, '.select2-results li'))
+        )
+        city_options = driver.find_elements_by_css_selector('.select2-results li')
+        city_names_from_browser = {option.text for option in city_options}
+        city_names_from_db = set(City.objects.values_list('name', flat=True))
+        assert len(city_names_from_browser) == City.objects.count()
+        assert city_names_from_browser == city_names_from_db
+
+        # selecting a country really does it
+        country_container.click()
+        WebDriverWait(driver, 60).until(
+            expected_conditions.presence_of_element_located((By.CSS_SELECTOR, '.select2-results li:nth-child(2)'))
+        )
+        country_option = driver.find_element_by_css_selector('.select2-results li:nth-child(2)')
+        country_name = country_option.text
+        country_option.click()
+        assert country_name == country_container.text
+
+        # clicking city select2 lists reduced list of cities belonging to the country
+        city_container.click()
+        WebDriverWait(driver, 60).until(
+            expected_conditions.presence_of_element_located((By.CSS_SELECTOR, '.select2-results li'))
+        )
+        city_options = driver.find_elements_by_css_selector('.select2-results li')
+        city_names_from_browser = {option.text for option in city_options}
+        city_names_from_db = set(Country.objects.get(name=country_name).cities.values_list('name', flat=True))
+        assert len(city_names_from_browser) != City.objects.count()
+        assert city_names_from_browser == city_names_from_db
+
+        # selecting a city reaaly does it
+        city_option = driver.find_element_by_css_selector('.select2-results li:nth-child(2)')
+        city_name = city_option.text
+        city_option.click()
+        assert city_name == city_container.text
+
+        # clicking country select2 lists reduced list to the only country available to the city
+        country_container.click()
+        WebDriverWait(driver, 60).until(
+            expected_conditions.presence_of_element_located((By.CSS_SELECTOR, '.select2-results li'))
+        )
+        country_options = driver.find_elements_by_css_selector('.select2-results li')
+        country_names_from_browser = {option.text for option in country_options}
+        country_names_from_db = {City.objects.get(name=city_name).country.name}
+        assert len(country_names_from_browser) != Country.objects.count()
+        assert country_names_from_browser == country_names_from_db

tests/test_views.py

@@ -4,13 +4,20 @@ from __future__ import absolute_import, unicode_literals
 import json
 
 from django.core import signing
-from django.core.urlresolvers import reverse
 from django.utils.encoding import smart_text
 
+from django_select2.cache import cache
 from django_select2.forms import ModelSelect2Widget
-from tests.testapp.forms import AlbumModelSelect2WidgetForm
+from tests.testapp.forms import (
+    AlbumModelSelect2WidgetForm, ArtistCustomTitleWidget
+)
 from tests.testapp.models import Genre
 
+try:
+    from django.urls import reverse
+except ImportError:
+    from django.core.urlresolvers import reverse
+
 
 class TestAutoResponseView(object):
     def test_get(self, client, artists):
@@ -66,3 +73,32 @@ class TestAutoResponseView(object):
         assert response.status_code == 200
         data = json.loads(response.content.decode('utf-8'))
         assert data['more'] is False
+
+    def test_label_from_instance(self, artists, client):
+        url = reverse('django_select2-json')
+
+        form = AlbumModelSelect2WidgetForm()
+        form.fields['artist'].widget = ArtistCustomTitleWidget()
+        assert form.as_p()
+        field_id = signing.dumps(id(form.fields['artist'].widget))
+
+        artist = artists[0]
+        response = client.get(url, {'field_id': field_id, 'term': artist.title})
+        assert response.status_code == 200
+
+        data = json.loads(response.content.decode('utf-8'))
+        assert data['results']
+        assert {'id': artist.pk, 'text': smart_text(artist.title.upper())} in data['results']
+
+    def test_url_check(self, client, artists):
+        artist = artists[0]
+        form = AlbumModelSelect2WidgetForm()
+        assert form.as_p()
+        field_id = signing.dumps(id(form.fields['artist'].widget))
+        cache_key = form.fields['artist'].widget._get_cache_key()
+        widget_dict = cache.get(cache_key)
+        widget_dict['url'] = 'yet/another/url'
+        cache.set(cache_key, widget_dict)
+        url = reverse('django_select2-json')
+        response = client.get(url, {'field_id': field_id, 'term': artist.title})
+        assert response.status_code == 404

tests/testapp/.coverage

@@ -0,0 +1 @@
+!coverage.py: This is a private format, don't read it directly!{"lines":{}}

tests/testapp/forms.py

@@ -2,6 +2,7 @@
 from __future__ import absolute_import, unicode_literals
 
 from django import forms
+from django.utils.encoding import force_text
 
 from django_select2.forms import (
     HeavySelect2MultipleWidget, HeavySelect2Widget, ModelSelect2MultipleWidget,
@@ -9,7 +10,7 @@ from django_select2.forms import (
     Select2Widget
 )
 from tests.testapp import models
-from tests.testapp.models import Album
+from tests.testapp.models import Album, City, Country
 
 
 class TitleSearchFieldMixin(object):
@@ -34,6 +35,26 @@ class GenreSelect2TagWidget(TitleSearchFieldMixin, ModelSelect2TagWidget):
         self.get_queryset().create(title=value)
 
 
+class ArtistCustomTitleWidget(ModelSelect2Widget):
+    model = models.Artist
+    search_fields = [
+        'title__icontains'
+    ]
+
+    def label_from_instance(self, obj):
+        return force_text(obj.title).upper()
+
+
+class GenreCustomTitleWidget(ModelSelect2Widget):
+    model = models.Genre
+    search_fields = [
+        'title__icontains'
+    ]
+
+    def label_from_instance(self, obj):
+        return force_text(obj.title).upper()
+
+
 class AlbumSelect2WidgetForm(forms.ModelForm):
     class Meta:
         model = models.Album
@@ -69,16 +90,14 @@ class AlbumModelSelect2WidgetForm(forms.ModelForm):
             'primary_genre',
         )
         widgets = {
-            'artist': ModelSelect2Widget(
-                model=models.Artist,
-                search_fields=['title__icontains']
-            ),
-            'primary_genre': ModelSelect2Widget(
-                model=models.Genre,
-                search_fields=['title__icontains']
-            ),
+            'artist': ArtistCustomTitleWidget(),
+            'primary_genre': GenreCustomTitleWidget(),
         }
 
+    def __init__(self, *args, **kwargs):
+        super(AlbumModelSelect2WidgetForm, self).__init__(*args, **kwargs)
+        self.fields['primary_genre'].initial = 2
+
 
 class AlbumModelSelect2MultipleWidgetRequiredForm(forms.ModelForm):
     class Meta:
@@ -98,7 +117,13 @@ class ArtistModelSelect2MultipleWidgetForm(forms.Form):
     genres = forms.ModelMultipleChoiceField(widget=ModelSelect2MultipleWidget(
         queryset=models.Genre.objects.all(),
         search_fields=['title__icontains'],
-    ), queryset=models.Genre.objects.all(), required=False)
+    ), queryset=models.Genre.objects.all(), required=True)
+
+    featured_artists = forms.ModelMultipleChoiceField(widget=ModelSelect2MultipleWidget(
+        queryset=models.Artist.objects.all(),
+        search_fields=['title__icontains'],
+    ), queryset=models.Artist.objects.all(), required=False)
+
 
 NUMBER_CHOICES = [
     (1, 'One'),
@@ -114,23 +139,33 @@ class Select2WidgetForm(forms.Form):
 
 class HeavySelect2WidgetForm(forms.Form):
     artist = forms.ChoiceField(
-        widget=HeavySelect2Widget(data_view='heavy_data', choices=NUMBER_CHOICES)
+        widget=HeavySelect2Widget(data_view='heavy_data_1'),
+        choices=NUMBER_CHOICES
     )
     primary_genre = forms.ChoiceField(
-        widget=HeavySelect2Widget(data_view='heavy_data', choices=NUMBER_CHOICES),
-        required=False
+        widget=HeavySelect2Widget(data_view='heavy_data_2'),
+        required=False,
+        choices=NUMBER_CHOICES
     )
 
 
 class HeavySelect2MultipleWidgetForm(forms.Form):
+    title = forms.CharField(max_length=50)
     genres = forms.MultipleChoiceField(
-        widget=HeavySelect2MultipleWidget(data_view='heavy_data', choices=NUMBER_CHOICES)
+        widget=HeavySelect2MultipleWidget(data_view='heavy_data_1', choices=NUMBER_CHOICES),
+        choices=NUMBER_CHOICES
     )
     featured_artists = forms.MultipleChoiceField(
-        widget=HeavySelect2MultipleWidget(data_view='heavy_data', choices=NUMBER_CHOICES),
+        widget=HeavySelect2MultipleWidget(data_view='heavy_data_2', choices=NUMBER_CHOICES),
+        choices=NUMBER_CHOICES,
         required=False
     )
 
+    def clean_title(self):
+        if len(self.cleaned_data['title']) < 3:
+            raise forms.ValidationError("Title must have more than 3 characters.")
+        return self.cleaned_data["title"]
+
 
 class ModelSelect2TagWidgetForm(forms.ModelForm):
     class Meta:
@@ -139,3 +174,27 @@ class ModelSelect2TagWidgetForm(forms.ModelForm):
         widgets = {
             'genres': GenreSelect2TagWidget
         }
+
+
+class AddressChainedSelect2WidgetForm(forms.Form):
+    country = forms.ModelChoiceField(
+        queryset=Country.objects.all(),
+        label='Country',
+        widget=ModelSelect2Widget(
+            model=Country,
+            search_fields=['name__icontains'],
+            max_results=500,
+            dependent_fields={'city': 'cities'},
+        )
+    )
+
+    city = forms.ModelChoiceField(
+        queryset=City.objects.all(),
+        label='City',
+        widget=ModelSelect2Widget(
+            model=City,
+            search_fields=['name__icontains'],
+            dependent_fields={'country': 'country'},
+            max_results=500,
+        )
+    )

tests/testapp/models.py

@@ -25,10 +25,28 @@ class Artist(models.Model):
 @python_2_unicode_compatible
 class Album(models.Model):
     title = models.CharField(max_length=255)
-    artist = models.ForeignKey(Artist)
+    artist = models.ForeignKey(Artist, on_delete=models.CASCADE)
     featured_artists = models.ManyToManyField(Artist, blank=True, related_name='featured_album_set')
-    primary_genre = models.ForeignKey(Genre, blank=True, null=True, related_name='primary_album_set')
+    primary_genre = models.ForeignKey(Genre, on_delete=models.CASCADE, blank=True, null=True,
+                                      related_name='primary_album_set')
     genres = models.ManyToManyField(Genre)
 
     def __str__(self):
         return self.title
+
+
+@python_2_unicode_compatible
+class Country(models.Model):
+    name = models.CharField(max_length=255)
+
+    def __str__(self):
+        return self.name
+
+
+@python_2_unicode_compatible
+class City(models.Model):
+    name = models.CharField(max_length=255)
+    country = models.ForeignKey('Country', related_name="cities", on_delete=models.CASCADE)
+
+    def __str__(self):
+        return self.name

tests/testapp/settings.py

@@ -33,9 +33,13 @@ MEDIA_ROOT = os.path.join(BASE_DIR, 'media')
 SITE_ID = 1
 ROOT_URLCONF = 'tests.testapp.urls'
 
-TEMPLATE_DIRS = (
-    os.path.join(BASE_DIR, "templates"),
-)
+TEMPLATES = [
+    {
+        'BACKEND': 'django.template.backends.django.DjangoTemplates',
+        'APP_DIRS': True,
+        'DIRS': ['templates'],
+    },
+]
 
 SECRET_KEY = '123456'
 
@@ -43,8 +47,11 @@ USE_L10N = True
 
 if os.environ.get('TRAVIS'):
     CACHES = {
-        'default': {
-            'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',
-            'LOCATION': 'localhost:11211',
+        "default": {
+            "BACKEND": "django_redis.cache.RedisCache",
+            "LOCATION": "redis://127.0.0.1:6379/1",
+            "OPTIONS": {
+                "CLIENT_CLASS": "django_redis.client.DefaultClient",
+            }
         }
     }

tests/testapp/templates/form.html

@@ -15,11 +15,11 @@
   {{ form }}
   <input type="submit" value="Submit Form"/>
 </form>
-<script src="{% static '//code.jquery.com/jquery-2.1.4.min.js' %}"></script>
+<script src="//code.jquery.com/jquery-2.1.4.min.js"></script>
 <script type="text/javascript">
   window.onerror = function (msg) {
     $("body").attr("JSError", msg);
   }
 </script>
 {{ form.media.js }}
-</body>
+</body>

tests/testapp/urls.py

@@ -1,22 +1,22 @@
 # -*- conding:utf-8 -*-
 from __future__ import absolute_import, unicode_literals
 
-from django.conf.urls import include, patterns, url
+from django.conf.urls import include, url
 
 from .forms import (
-    AlbumModelSelect2WidgetForm, HeavySelect2MultipleWidgetForm,
-    HeavySelect2WidgetForm, ModelSelect2TagWidgetForm, Select2WidgetForm
+    AddressChainedSelect2WidgetForm, AlbumModelSelect2WidgetForm,
+    HeavySelect2MultipleWidgetForm, HeavySelect2WidgetForm,
+    ModelSelect2TagWidgetForm, Select2WidgetForm
 )
-from .views import TemplateFormView, heavy_data
+from .views import TemplateFormView, heavy_data_1, heavy_data_2
 
-urlpatterns = patterns(
-    '',
+urlpatterns = [
     url(r'^select2_widget/$',
         TemplateFormView.as_view(form_class=Select2WidgetForm), name='select2_widget'),
     url(r'^heavy_select2_widget/$',
         TemplateFormView.as_view(form_class=HeavySelect2WidgetForm), name='heavy_select2_widget'),
     url(r'^heavy_select2_multiple_widget/$',
-        TemplateFormView.as_view(form_class=HeavySelect2MultipleWidgetForm),
+        TemplateFormView.as_view(form_class=HeavySelect2MultipleWidgetForm, success_url='/'),
         name='heavy_select2_multiple_widget'),
 
     url(r'^model_select2_widget/$',
@@ -27,7 +27,12 @@ urlpatterns = patterns(
         TemplateFormView.as_view(form_class=ModelSelect2TagWidgetForm),
         name='model_select2_tag_widget'),
 
-    url(r'^heavy_data/$', heavy_data, name='heavy_data'),
+    url(r'^model_chained_select2_widget/$',
+        TemplateFormView.as_view(form_class=AddressChainedSelect2WidgetForm),
+        name='model_chained_select2_widget'),
+
+    url(r'^heavy_data_1/$', heavy_data_1, name='heavy_data_1'),
+    url(r'^heavy_data_2/$', heavy_data_2, name='heavy_data_2'),
 
     url(r'^select2/', include('django_select2.urls')),
-)
+]

tests/testapp/views.py

@@ -11,7 +11,17 @@ class TemplateFormView(FormView):
     template_name = 'form.html'
 
 
-def heavy_data(request):
+def heavy_data_1(request):
+    term = request.GET.get("term", "")
     numbers = ['Zero', 'One', 'Two', 'Three', 'Four', 'Five']
+    numbers = filter(lambda num: term.lower() in num.lower(), numbers)
+    results = [{'id': index, 'text': value} for (index, value) in enumerate(numbers)]
+    return HttpResponse(json.dumps({'err': 'nil', 'results': results}), content_type='application/json')
+
+
+def heavy_data_2(request):
+    term = request.GET.get("term", "")
+    numbers = ['Six', 'Seven', 'Eight', 'Nine', 'Ten', 'Fortytwo']
+    numbers = filter(lambda num: term.lower() in num.lower(), numbers)
     results = [{'id': index, 'text': value} for (index, value) in enumerate(numbers)]
     return HttpResponse(json.dumps({'err': 'nil', 'results': results}), content_type='application/json')

tox.ini

@@ -0,0 +1,34 @@
+[tox]
+envlist = py{27,35,36}-dj{18,110,111,master},qa,docs
+[testenv]
+setenv=
+    DISPLAY=:99.0
+    PYTHONPATH = {toxinidir}
+deps=
+    -rrequirements-dev.txt
+    dj18: https://github.com/django/django/archive/stable/1.8.x.tar.gz#egg=django
+    dj110: https://github.com/django/django/archive/stable/1.10.x.tar.gz#egg=django
+    dj111: https://github.com/django/django/archive/stable/1.11.x.tar.gz#egg=django
+    djmaster: https://github.com/django/django/archive/master.tar.gz#egg=django
+commands=
+    coverage run --source=django_select2 -m 'pytest' \
+        --basetemp={envtmpdir} \
+        --ignore=.tox \
+        {posargs}
+
+[testenv:qa]
+changedir={toxinidir}
+deps=
+    -rrequirements-dev.txt
+commands=
+    isort --check-only --recursive --diff {posargs}
+    flake8 --jobs=2 {posargs}
+    pydocstyle --verbose --explain --source --count {posargs}
+
+[testenv:docs]
+whitelist_externals=make
+changedir={toxinidir}/docs
+deps=
+    -rrequirements-dev.txt
+    https://github.com/django/django/archive/stable/1.10.x.tar.gz#egg=django
+commands=make spelling