Implemented generic_m2m support

autocomplete_light/__init__.py

@@ -6,4 +6,4 @@
     GenericChannelBase
 from .widgets import AutocompleteWidget
 from .forms import get_widgets_dict, modelform_factory
-from .generic import GenericForeignKeyField, GenericModelForm
+from .generic import GenericModelForm, GenericForeignKeyField

autocomplete_light/contrib/generic_m2m.py

@@ -0,0 +1,83 @@
+"""
+``autocomplete_light.contrib.generic_m2m`` couples django-autocomplete-light
+with django-generic-m2m.
+
+Generic many to many are supported since 0.5. It depends on `django-generic-m2m
+<http://django-generic-m2m.rtfd.org>`_ external apps. Follow django-generic-m2m
+installation documentation, but at the time of writing it barely consists of
+adding the ``genericm2m`` to ``INSTALLED_APPS``, and adding a field to models
+that should have a generic m2m relation. So, kudos to the maintainers of
+django-generic-m2m, fantastic app, use it for generic many to many relations.
+
+See examples in ``test_project/generic_m2m_example``.
+"""
+from genericm2m.models import RelatedObjectsDescriptor
+
+from ..generic import GenericForeignKeyField, GenericModelForm
+
+
+class GenericModelForm(GenericModelForm):
+    """
+    Extension of autocomplete_light.GenericModelForm, that handles
+    genericm2m's RelatedObjectsDescriptor.
+    """
+
+    def __init__(self, *args, **kwargs):
+        """
+        Add related objects to initial for each generic m2m field.
+        """
+        super(GenericModelForm, self).__init__(*args, **kwargs)
+
+        for name, field in self.generic_m2m_fields():
+            related_objects = getattr(self.instance, name).all()
+            self.initial[name] = [x.object for x in related_objects]
+
+    def generic_m2m_fields(self):
+        """
+        Yield name, field for each RelatedObjectsDescriptor of the model of
+        this ModelForm.
+        """
+        for name, field in self.fields.items():
+            if not isinstance(field, GenericManyToMany):
+                continue
+
+            model_class_attr = getattr(self._meta.model, name, None)
+            if not isinstance(model_class_attr, RelatedObjectsDescriptor):
+                continue
+
+            yield name, field
+
+    def save(self, commit=True):
+        """
+        Save selected generic m2m relations after saving the model.
+        """
+        model = super(GenericModelForm, self).save(commit)
+
+        for name, field in self.generic_m2m_fields():
+            model_attr = getattr(model, name)
+            selected_relations = self.cleaned_data.get(name, [])
+
+            for related in model_attr.all():
+                if related.object not in selected_relations:
+                    model_attr.remove(related)
+
+            for related in selected_relations:
+                model_attr.connect(related)
+
+        return model
+
+
+class GenericManyToMany(GenericForeignKeyField):
+    """
+    Simple form field that converts strings to models.
+    """
+    def prepare_value(self, value):
+        if hasattr(value, '__iter__'):
+            return [super(GenericManyToMany, self).prepare_value(v) \
+                for v in value]
+        return super(GenericManyToMany, self).prepare_value(value)
+
+    def to_python(self, value):
+        if hasattr(value, '__iter__'):
+            return [super(GenericManyToMany, self).to_python(v) for v in value]
+        return super(GenericManyToMany, self).to_python(value)

autocomplete_light/generic.py

@@ -4,6 +4,8 @@
 from django.contrib.contenttypes.generic import GenericForeignKey
 from django.contrib.contenttypes.models import ContentType
 
+__all__ = ('GenericModelForm', 'GenericForeignKeyField')
+
 
 class GenericModelForm(forms.ModelForm):
     """

cloc.txt

@@ -1,12 +1,15 @@
-http://cloc.sourceforge.net v 1.53  T=0.5 s (40.0 files/s, 3562.0 lines/s)
+      23 text files.
+classified 23 files      23 unique files.                              
+       3 files ignored.
+
+http://cloc.sourceforge.net v 1.53  T=0.5 s (42.0 files/s, 3732.0 lines/s)
 -------------------------------------------------------------------------------
 Language                     files          blank        comment           code
 -------------------------------------------------------------------------------
-Python                          13            261            485            477
+Python                          14            280            513            515
 Javascript                       3             54             47            385
 HTML                             3              9              0             50
 CSS                              1              0              0             13
 -------------------------------------------------------------------------------
-SUM:                            20            324            532            925
+SUM:                            21            343            560            963
 -------------------------------------------------------------------------------
-

docs/source/generic.rst

@@ -1,29 +1,52 @@
-Generic relations support
+GenericForeignKey support
 =========================
 
 Generic foreign keys are supported since 0.4.
 
-Example
--------
-
-Such a form:
+GenericChannelBase
+------------------
 
-.. literalinclude:: ../../test_api_project/project_specific/generic_form_example.py
-   :language: python
+.. automodule:: autocomplete_light.channel.generic
+   :members:
 
-Would work with such a channel:
+Example
+~~~~~~~
 
 .. literalinclude:: ../../test_api_project/project_specific/generic_channel_example.py
    :language: python
 
-Form
-----
+GenericForeignKeyField
+----------------------
 
 .. automodule:: autocomplete_light.generic
    :members:
 
-Channel
--------
+Example
+~~~~~~~
 
-.. automodule:: autocomplete_light.channel.generic
+.. literalinclude:: ../../test_api_project/project_specific/generic_form_example.py
+   :language: python
+
+GenericManyToMany
+-----------------
+
+.. automodule:: autocomplete_light.contrib.generic_m2m
    :members:
+
+Example
+~~~~~~~
+
+Example model with ``related``:
+
+.. literalinclude:: ../../test_project/generic_m2m_example/models.py
+   :language: python
+
+Example ``generic_m2m.GenericModelForm`` usage:
+
+.. literalinclude:: ../../test_project/generic_m2m_example/forms.py
+   :language: python
+
+Example ``ModelAdmin``:
+
+.. literalinclude:: ../../test_project/generic_m2m_example/admin.py
+   :language: python

test_project/generic_m2m_example/admin.py

@@ -0,0 +1,9 @@
+from django.contrib import admin
+
+from models import ModelGroup
+from forms import ModelGroupForm
+
+
+class ModelGroupAdmin(admin.ModelAdmin):
+    form = ModelGroupForm
+admin.site.register(ModelGroup, ModelGroupAdmin)

test_project/generic_m2m_example/forms.py

@@ -0,0 +1,13 @@
+import autocomplete_light
+from autocomplete_light.contrib.generic_m2m import GenericModelForm, \
+    GenericManyToMany
+
+from models import ModelGroup
+
+
+class ModelGroupForm(GenericModelForm):
+    related = GenericManyToMany(
+        widget=autocomplete_light.AutocompleteWidget('MyGenericChannel'))
+
+    class Meta:
+        model = ModelGroup

test_project/generic_m2m_example/models.py

@@ -0,0 +1,13 @@
+from django.db import models
+from django.db.models import signals
+from django.contrib.contenttypes import generic
+
+from genericm2m.models import RelatedObjectsDescriptor
+
+class ModelGroup(models.Model):
+    name = models.CharField(max_length=100)
+
+    related = RelatedObjectsDescriptor()
+
+    def __unicode__(self):
+        return self.name

test_project/project_specific/models.py

@@ -3,6 +3,8 @@
 from django.contrib.contenttypes.models import ContentType
 from django.contrib.contenttypes import generic
 
+from genericm2m.models import RelatedObjectsDescriptor
+
 import cities_light
 
 
@@ -38,5 +40,7 @@ class TaggedItem(models.Model):
     object_id = models.PositiveIntegerField()
     content_object = generic.GenericForeignKey('content_type', 'object_id')
 
+    related = RelatedObjectsDescriptor()
+
     def __unicode__(self):
         return self.tag

test_project/test_project/settings.py

@@ -131,6 +131,8 @@
     'south',
     'autocomplete_light',
     'project_specific',
+    'genericm2m',
+    'generic_m2m_example',
     # Uncomment the next line to enable admin documentation:
     # 'django.contrib.admindocs',
 )