Convert `admin.py` into a package.

Clears up the code and prepare to receive more changes for formset support.

polymorphic/admin/__init__.py

@@ -0,0 +1,15 @@
+"""
+ModelAdmin code to display polymorphic models.
+
+The admin consists of a parent admin (which shows in the admin with a list),
+and a child admin (which is used internally to show the edit/delete dialog).
+"""
+from .parentadmin import PolymorphicParentModelAdmin
+from .childadmin import PolymorphicChildModelAdmin
+from .forms import PolymorphicModelChoiceForm
+from .filters import PolymorphicChildModelFilter
+
+__all__ = (
+    'PolymorphicModelChoiceForm', 'PolymorphicParentModelAdmin',
+    'PolymorphicChildModelAdmin', 'PolymorphicChildModelFilter'
+)

polymorphic/admin/childadmin.py

@@ -0,0 +1,169 @@
+"""
+The child admin displays the change/delete view of the subclass model.
+"""
+from django.contrib import admin
+from django.core.urlresolvers import resolve
+from django.utils import six
+from django.utils.translation import ugettext_lazy as _
+
+
+class PolymorphicChildModelAdmin(admin.ModelAdmin):
+    """
+    The *optional* base class for the admin interface of derived models.
+
+    This base class defines some convenience behavior for the admin interface:
+
+    * It corrects the breadcrumbs in the admin pages.
+    * It adds the base model to the template lookup paths.
+    * It allows to set ``base_form`` so the derived class will automatically include other fields in the form.
+    * It allows to set ``base_fieldsets`` so the derived class will automatically display any extra fields.
+
+    The ``base_model`` attribute must be set.
+    """
+    base_model = None
+    base_form = None
+    base_fieldsets = None
+    extra_fieldset_title = _("Contents")  # Default title for extra fieldset
+    show_in_index = False
+
+    def get_form(self, request, obj=None, **kwargs):
+        # The django admin validation requires the form to have a 'class Meta: model = ..'
+        # attribute, or it will complain that the fields are missing.
+        # However, this enforces all derived ModelAdmin classes to redefine the model as well,
+        # because they need to explicitly set the model again - it will stick with the base model.
+        #
+        # Instead, pass the form unchecked here, because the standard ModelForm will just work.
+        # If the derived class sets the model explicitly, respect that setting.
+        kwargs.setdefault('form', self.base_form or self.form)
+
+        # prevent infinite recursion in django 1.6+
+        if not getattr(self, 'declared_fieldsets', None):
+            kwargs.setdefault('fields', None)
+
+        return super(PolymorphicChildModelAdmin, self).get_form(request, obj, **kwargs)
+
+    def get_model_perms(self, request):
+        match = resolve(request.path)
+
+        if not self.show_in_index and match.app_name == 'admin' and match.url_name in ('index', 'app_list'):
+            return {'add': False, 'change': False, 'delete': False}
+        return super(PolymorphicChildModelAdmin, self).get_model_perms(request)
+
+    @property
+    def change_form_template(self):
+        opts = self.model._meta
+        app_label = opts.app_label
+
+        # Pass the base options
+        base_opts = self.base_model._meta
+        base_app_label = base_opts.app_label
+
+        return [
+            "admin/%s/%s/change_form.html" % (app_label, opts.object_name.lower()),
+            "admin/%s/change_form.html" % app_label,
+            # Added:
+            "admin/%s/%s/change_form.html" % (base_app_label, base_opts.object_name.lower()),
+            "admin/%s/change_form.html" % base_app_label,
+            "admin/polymorphic/change_form.html",
+            "admin/change_form.html"
+        ]
+
+    @property
+    def delete_confirmation_template(self):
+        opts = self.model._meta
+        app_label = opts.app_label
+
+        # Pass the base options
+        base_opts = self.base_model._meta
+        base_app_label = base_opts.app_label
+
+        return [
+            "admin/%s/%s/delete_confirmation.html" % (app_label, opts.object_name.lower()),
+            "admin/%s/delete_confirmation.html" % app_label,
+            # Added:
+            "admin/%s/%s/delete_confirmation.html" % (base_app_label, base_opts.object_name.lower()),
+            "admin/%s/delete_confirmation.html" % base_app_label,
+            "admin/polymorphic/delete_confirmation.html",
+            "admin/delete_confirmation.html"
+        ]
+
+    @property
+    def object_history_template(self):
+        opts = self.model._meta
+        app_label = opts.app_label
+
+        # Pass the base options
+        base_opts = self.base_model._meta
+        base_app_label = base_opts.app_label
+
+        return [
+            "admin/%s/%s/object_history.html" % (app_label, opts.object_name.lower()),
+            "admin/%s/object_history.html" % app_label,
+            # Added:
+            "admin/%s/%s/object_history.html" % (base_app_label, base_opts.object_name.lower()),
+            "admin/%s/object_history.html" % base_app_label,
+            "admin/polymorphic/object_history.html",
+            "admin/object_history.html"
+        ]
+
+    def render_change_form(self, request, context, add=False, change=False, form_url='', obj=None):
+        context.update({
+            'base_opts': self.base_model._meta,
+        })
+        return super(PolymorphicChildModelAdmin, self).render_change_form(request, context, add=add, change=change, form_url=form_url, obj=obj)
+
+    def delete_view(self, request, object_id, context=None):
+        extra_context = {
+            'base_opts': self.base_model._meta,
+        }
+        return super(PolymorphicChildModelAdmin, self).delete_view(request, object_id, extra_context)
+
+    def history_view(self, request, object_id, extra_context=None):
+        # Make sure the history view can also display polymorphic breadcrumbs
+        context = {
+            'base_opts': self.base_model._meta,
+        }
+        if extra_context:
+            context.update(extra_context)
+        return super(PolymorphicChildModelAdmin, self).history_view(request, object_id, extra_context=context)
+
+
+    # ---- Extra: improving the form/fieldset default display ----
+
+    def get_fieldsets(self, request, obj=None):
+        # If subclass declares fieldsets, this is respected
+        if (hasattr(self, 'declared_fieldset') and self.declared_fieldsets) \
+           or not self.base_fieldsets:
+            return super(PolymorphicChildModelAdmin, self).get_fieldsets(request, obj)
+
+        # Have a reasonable default fieldsets,
+        # where the subclass fields are automatically included.
+        other_fields = self.get_subclass_fields(request, obj)
+
+        if other_fields:
+            return (
+                self.base_fieldsets[0],
+                (self.extra_fieldset_title, {'fields': other_fields}),
+            ) + self.base_fieldsets[1:]
+        else:
+            return self.base_fieldsets
+
+    def get_subclass_fields(self, request, obj=None):
+        # Find out how many fields would really be on the form,
+        # if it weren't restricted by declared fields.
+        exclude = list(self.exclude or [])
+        exclude.extend(self.get_readonly_fields(request, obj))
+
+        # By not declaring the fields/form in the base class,
+        # get_form() will populate the form with all available fields.
+        form = self.get_form(request, obj, exclude=exclude)
+        subclass_fields = list(six.iterkeys(form.base_fields)) + list(self.get_readonly_fields(request, obj))
+
+        # Find which fields are not part of the common fields.
+        for fieldset in self.base_fieldsets:
+            for field in fieldset[1]['fields']:
+                try:
+                    subclass_fields.remove(field)
+                except ValueError:
+                    pass   # field not found in form, Django will raise exception later.
+        return subclass_fields

polymorphic/admin/filters.py

@@ -0,0 +1,29 @@
+from django.contrib import admin
+from django.core.exceptions import PermissionDenied
+from django.utils.translation import ugettext_lazy as _
+
+
+class PolymorphicChildModelFilter(admin.SimpleListFilter):
+    """
+    An admin list filter for the PolymorphicParentModelAdmin which enables
+    filtering by its child models.
+    """
+    title = _('Type')
+    parameter_name = 'polymorphic_ctype'
+
+    def lookups(self, request, model_admin):
+        return model_admin.get_child_type_choices(request, 'change')
+
+    def queryset(self, request, queryset):
+        try:
+            value = int(self.value())
+        except TypeError:
+            value = None
+        if value:
+            # ensure the content type is allowed
+            for choice_value, _ in self.lookup_choices:
+                if choice_value == value:
+                    return queryset.filter(polymorphic_ctype_id=choice_value)
+            raise PermissionDenied(
+                'Invalid ContentType "{0}". It must be registered as child model.'.format(value))
+        return queryset

polymorphic/admin/forms.py

@@ -0,0 +1,18 @@
+from django import forms
+from django.contrib.admin.widgets import AdminRadioSelect
+from django.utils.translation import ugettext_lazy as _
+
+
+class PolymorphicModelChoiceForm(forms.Form):
+    """
+    The default form for the ``add_type_form``. Can be overwritten and replaced.
+    """
+    #: Define the label for the radiofield
+    type_label = _('Type')
+
+    ct_id = forms.ChoiceField(label=type_label, widget=AdminRadioSelect(attrs={'class': 'radiolist'}))
+
+    def __init__(self, *args, **kwargs):
+        # Allow to easily redefine the label (a commonly expected usecase)
+        super(PolymorphicModelChoiceForm, self).__init__(*args, **kwargs)
+        self.fields['ct_id'].label = self.type_label

polymorphic/admin/parentadmin.py

@@ -1,27 +1,26 @@
 """
-ModelAdmin code to display polymorphic models.
+The parent admin displays the list view of the base model.
 """
 import sys
 import warnings
 
 import django
-from django import forms
 from django.conf.urls import url
 from django.contrib import admin
 from django.contrib.admin.helpers import AdminErrorList, AdminForm
-from django.contrib.admin.widgets import AdminRadioSelect
 from django.contrib.contenttypes.models import ContentType
 from django.core.exceptions import PermissionDenied
-from django.core.urlresolvers import RegexURLResolver, resolve
+from django.core.urlresolvers import RegexURLResolver
 from django.http import Http404, HttpResponseRedirect
 from django.shortcuts import render_to_response
 from django.template.context import RequestContext
-from django.utils import six
 from django.utils.encoding import force_text
 from django.utils.http import urlencode
 from django.utils.safestring import mark_safe
 from django.utils.translation import ugettext_lazy as _
 
+from .forms import PolymorphicModelChoiceForm
+
 try:
     # Django 1.6 implements this
     from django.contrib.admin.templatetags.admin_urls import add_preserved_filters
@@ -33,12 +32,6 @@ if sys.version_info[0] >= 3:
     long = int
 
 
-__all__ = (
-    'PolymorphicModelChoiceForm', 'PolymorphicParentModelAdmin',
-    'PolymorphicChildModelAdmin', 'PolymorphicChildModelFilter'
-)
-
-
 class RegistrationClosed(RuntimeError):
     "The admin model can't be registered anymore at this point."
     pass
@@ -49,47 +42,6 @@ class ChildAdminNotRegistered(RuntimeError):
     pass
 
 
-class PolymorphicModelChoiceForm(forms.Form):
-    """
-    The default form for the ``add_type_form``. Can be overwritten and replaced.
-    """
-    #: Define the label for the radiofield
-    type_label = _('Type')
-
-    ct_id = forms.ChoiceField(label=type_label, widget=AdminRadioSelect(attrs={'class': 'radiolist'}))
-
-    def __init__(self, *args, **kwargs):
-        # Allow to easily redefine the label (a commonly expected usecase)
-        super(PolymorphicModelChoiceForm, self).__init__(*args, **kwargs)
-        self.fields['ct_id'].label = self.type_label
-
-
-class PolymorphicChildModelFilter(admin.SimpleListFilter):
-    """
-    An admin list filter for the PolymorphicParentModelAdmin which enables
-    filtering by its child models.
-    """
-    title = _('Type')
-    parameter_name = 'polymorphic_ctype'
-
-    def lookups(self, request, model_admin):
-        return model_admin.get_child_type_choices(request, 'change')
-
-    def queryset(self, request, queryset):
-        try:
-            value = int(self.value())
-        except TypeError:
-            value = None
-        if value:
-            # ensure the content type is allowed
-            for choice_value, _ in self.lookup_choices:
-                if choice_value == value:
-                    return queryset.filter(polymorphic_ctype_id=choice_value)
-            raise PermissionDenied(
-                'Invalid ContentType "{0}". It must be registered as child model.'.format(value))
-        return queryset
-
-
 class PolymorphicParentModelAdmin(admin.ModelAdmin):
     """
     A admin interface that can displays different change/delete pages, depending on the polymorphic model.
@@ -487,168 +439,6 @@ class PolymorphicParentModelAdmin(admin.ModelAdmin):
         ]
 
 
-class PolymorphicChildModelAdmin(admin.ModelAdmin):
-    """
-    The *optional* base class for the admin interface of derived models.
-
-    This base class defines some convenience behavior for the admin interface:
-
-    * It corrects the breadcrumbs in the admin pages.
-    * It adds the base model to the template lookup paths.
-    * It allows to set ``base_form`` so the derived class will automatically include other fields in the form.
-    * It allows to set ``base_fieldsets`` so the derived class will automatically display any extra fields.
-
-    The ``base_model`` attribute must be set.
-    """
-    base_model = None
-    base_form = None
-    base_fieldsets = None
-    extra_fieldset_title = _("Contents")  # Default title for extra fieldset
-    show_in_index = False
-
-    def get_form(self, request, obj=None, **kwargs):
-        # The django admin validation requires the form to have a 'class Meta: model = ..'
-        # attribute, or it will complain that the fields are missing.
-        # However, this enforces all derived ModelAdmin classes to redefine the model as well,
-        # because they need to explicitly set the model again - it will stick with the base model.
-        #
-        # Instead, pass the form unchecked here, because the standard ModelForm will just work.
-        # If the derived class sets the model explicitly, respect that setting.
-        kwargs.setdefault('form', self.base_form or self.form)
-
-        # prevent infinite recursion in django 1.6+
-        if not getattr(self, 'declared_fieldsets', None):
-            kwargs.setdefault('fields', None)
-
-        return super(PolymorphicChildModelAdmin, self).get_form(request, obj, **kwargs)
-
-    def get_model_perms(self, request):
-        match = resolve(request.path)
-
-        if not self.show_in_index and match.app_name == 'admin' and match.url_name in ('index', 'app_list'):
-            return {'add': False, 'change': False, 'delete': False}
-        return super(PolymorphicChildModelAdmin, self).get_model_perms(request)
-
-    @property
-    def change_form_template(self):
-        opts = self.model._meta
-        app_label = opts.app_label
-
-        # Pass the base options
-        base_opts = self.base_model._meta
-        base_app_label = base_opts.app_label
-
-        return [
-            "admin/%s/%s/change_form.html" % (app_label, opts.object_name.lower()),
-            "admin/%s/change_form.html" % app_label,
-            # Added:
-            "admin/%s/%s/change_form.html" % (base_app_label, base_opts.object_name.lower()),
-            "admin/%s/change_form.html" % base_app_label,
-            "admin/polymorphic/change_form.html",
-            "admin/change_form.html"
-        ]
-
-    @property
-    def delete_confirmation_template(self):
-        opts = self.model._meta
-        app_label = opts.app_label
-
-        # Pass the base options
-        base_opts = self.base_model._meta
-        base_app_label = base_opts.app_label
-
-        return [
-            "admin/%s/%s/delete_confirmation.html" % (app_label, opts.object_name.lower()),
-            "admin/%s/delete_confirmation.html" % app_label,
-            # Added:
-            "admin/%s/%s/delete_confirmation.html" % (base_app_label, base_opts.object_name.lower()),
-            "admin/%s/delete_confirmation.html" % base_app_label,
-            "admin/polymorphic/delete_confirmation.html",
-            "admin/delete_confirmation.html"
-        ]
-
-    @property
-    def object_history_template(self):
-        opts = self.model._meta
-        app_label = opts.app_label
-
-        # Pass the base options
-        base_opts = self.base_model._meta
-        base_app_label = base_opts.app_label
-
-        return [
-            "admin/%s/%s/object_history.html" % (app_label, opts.object_name.lower()),
-            "admin/%s/object_history.html" % app_label,
-            # Added:
-            "admin/%s/%s/object_history.html" % (base_app_label, base_opts.object_name.lower()),
-            "admin/%s/object_history.html" % base_app_label,
-            "admin/polymorphic/object_history.html",
-            "admin/object_history.html"
-        ]
-
-    def render_change_form(self, request, context, add=False, change=False, form_url='', obj=None):
-        context.update({
-            'base_opts': self.base_model._meta,
-        })
-        return super(PolymorphicChildModelAdmin, self).render_change_form(request, context, add=add, change=change, form_url=form_url, obj=obj)
-
-    def delete_view(self, request, object_id, context=None):
-        extra_context = {
-            'base_opts': self.base_model._meta,
-        }
-        return super(PolymorphicChildModelAdmin, self).delete_view(request, object_id, extra_context)
-
-    def history_view(self, request, object_id, extra_context=None):
-        # Make sure the history view can also display polymorphic breadcrumbs
-        context = {
-            'base_opts': self.base_model._meta,
-        }
-        if extra_context:
-            context.update(extra_context)
-        return super(PolymorphicChildModelAdmin, self).history_view(request, object_id, extra_context=context)
-
-
-    # ---- Extra: improving the form/fieldset default display ----
-
-    def get_fieldsets(self, request, obj=None):
-        # If subclass declares fieldsets, this is respected
-        if (hasattr(self, 'declared_fieldset') and self.declared_fieldsets) \
-           or not self.base_fieldsets:
-            return super(PolymorphicChildModelAdmin, self).get_fieldsets(request, obj)
-
-        # Have a reasonable default fieldsets,
-        # where the subclass fields are automatically included.
-        other_fields = self.get_subclass_fields(request, obj)
-
-        if other_fields:
-            return (
-                self.base_fieldsets[0],
-                (self.extra_fieldset_title, {'fields': other_fields}),
-            ) + self.base_fieldsets[1:]
-        else:
-            return self.base_fieldsets
-
-    def get_subclass_fields(self, request, obj=None):
-        # Find out how many fields would really be on the form,
-        # if it weren't restricted by declared fields.
-        exclude = list(self.exclude or [])
-        exclude.extend(self.get_readonly_fields(request, obj))
-
-        # By not declaring the fields/form in the base class,
-        # get_form() will populate the form with all available fields.
-        form = self.get_form(request, obj, exclude=exclude)
-        subclass_fields = list(six.iterkeys(form.base_fields)) + list(self.get_readonly_fields(request, obj))
-
-        # Find which fields are not part of the common fields.
-        for fieldset in self.base_fieldsets:
-            for field in fieldset[1]['fields']:
-                try:
-                    subclass_fields.remove(field)
-                except ValueError:
-                    pass   # field not found in form, Django will raise exception later.
-        return subclass_fields
-
-
 def _get_opt(model):
     try:
         return model._meta.app_label, model._meta.model_name  # Django 1.7 format