The dependency on swapper has been replaced with an incredibly simply

"registry". Client projects register their models and views during import
time with a decorator. The cms views use the registered classes to generate
pages and forms.

Furthermore, the example application now combines the app and the project in
one, inspired by this line in the Django documentation:

    There’s no restriction that a project package can’t also be considered
    an application and have models, etc.

cms/__init__.py

@@ -1,4 +1 @@
-from .decorators import register
-from .cms import SectionView, SectionFormView
-
 default_app_config = 'cms.apps.CmsConfig'

cms/cms.py

@@ -1,25 +0,0 @@
-from django.views.generic import edit
-from django.http import HttpResponseRedirect
-
-class SectionView:
-    '''Generic section view'''
-    template_name = 'cms/sections/section.html'
-
-    def __init__(self, request):
-        '''Initialize request attribute'''
-        self.request = request
-
-    def get_context_data(self, **kwargs):
-        '''Override this to customize a section's context'''
-        return kwargs
-
-class SectionFormView(edit.FormMixin, SectionView):
-    '''Generic section with associated form'''
-
-    def post(self, request):
-        '''Process form'''
-        form = self.get_form()
-        if form.is_valid():
-            form.save(request)
-            return HttpResponseRedirect(self.get_success_url())
-        return form

cms/decorators.py

@@ -1,25 +1,17 @@
-def register(verbose_name):
-    import swapper
-    Section = swapper.load_model('cms', 'Section')
+from cms import registry
 
-    '''Decorator to register a specific section type'''
-    def wrapper(view):
-        Section._cms_views[view.__name__.lower()] = view
-        Section.TYPES.append((view.__name__.lower(), verbose_name))
-        return view
-    return wrapper
+def page_model(cls):
+    '''Decorator to register the Page model'''
+    registry.page_class = cls
+    return cls
 
-# def register_model(verbose_name):
-#     '''Decorator to register a section subclass'''
-#     def wrapper(model):
-#         parent_model = model.__bases__[-1]
-#         parent_model.TYPES.append((model.__name__.lower(), verbose_name))
-#         return model
-#     return wrapper
+def section_model(cls):
+    '''Decorator to register the Section model'''
+    registry.section_class = cls
+    return cls
 
-# def register_view(section_class):
-#     '''Decorator to connect a section model to a view class'''
-#     def wrapper(model):
-#         section_class.view_class = model
-#         return model
-#     return wrapper
+def section_view(cls):
+    '''Decorator to register a view for a specific section'''
+    registry.views_per_type[cls.__name__.lower()] = cls
+    registry.section_class.TYPES.append((cls.__name__.lower(), cls.verbose_name))
+    return cls

cms/forms.py

@@ -1,4 +1,3 @@
-import swapper
 from django import forms
 from django.conf import settings
 from django.db.models import Prefetch
@@ -6,8 +5,7 @@ from django.contrib.contenttypes.models import ContentType
 from django.core.mail import EmailMessage
 from django.utils.translation import gettext_lazy as _
 
-Page = swapper.load_model('cms', 'Page')
-Section = swapper.load_model('cms', 'Section')
+from . import registry
 
 class PageForm(forms.ModelForm):
     def __init__(self, *args, **kwargs):
@@ -15,8 +13,8 @@ class PageForm(forms.ModelForm):
         self.label_suffix = ''
         extra = 1 if self.instance.pk else 2
         self.formsets = [forms.inlineformset_factory(
-            parent_model = Page,
-            model = Section,
+            parent_model = registry.page_class,
+            model = registry.section_class,
             form = SectionForm,
             extra=extra,
         )(
@@ -50,7 +48,7 @@ class PageForm(forms.ModelForm):
         return page
 
     class Meta:
-        model = Page
+        model = registry.page_class
         fields = '__all__'
 
 class SectionForm(forms.ModelForm):
@@ -73,7 +71,7 @@ class SectionForm(forms.ModelForm):
         for field in self.instance._meta.get_fields():
             if field.one_to_many:
                 formset = forms.inlineformset_factory(
-                    parent_model=Section,
+                    parent_model=registry.section_class,
                     model=field.related_model,
                     fields='__all__',
                     extra=extra,
@@ -116,7 +114,7 @@ class SectionForm(forms.ModelForm):
         return section
 
     class Meta:
-        model = Section
+        model = registry.section_class
         exclude = ['page']
 
 class ContactForm(forms.Form):

cms/migrations/0001_initial.py

@@ -1,61 +0,0 @@
-# Generated by Django 3.0.2 on 2020-02-16 14:27
-
-import cms.models
-from django.conf import settings
-from django.db import migrations, models
-import django.db.models.deletion
-import embed_video.fields
-
-
-class Migration(migrations.Migration):
-
-    initial = True
-
-    dependencies = [
-        migrations.swappable_dependency(settings.CMS_PAGE_MODEL),
-        ('contenttypes', '0002_remove_content_type_name'),
-    ]
-
-    operations = [
-        migrations.CreateModel(
-            name='Page',
-            fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('number', models.PositiveIntegerField(blank=True, verbose_name='number')),
-                ('title', cms.models.VarCharField(verbose_name='page')),
-                ('slug', models.SlugField(blank=True, unique=True, verbose_name='slug')),
-                ('menu', models.BooleanField(default=True, verbose_name='visible in menu')),
-            ],
-            options={
-                'verbose_name': 'Page',
-                'verbose_name_plural': 'Pages',
-                'ordering': ['number'],
-                'abstract': False,
-                'swappable': 'CMS_PAGE_MODEL',
-            },
-            bases=(cms.models.Numbered, models.Model),
-        ),
-        migrations.CreateModel(
-            name='Section',
-            fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('type', cms.models.VarCharField(verbose_name='type')),
-                ('number', models.PositiveIntegerField(blank=True, verbose_name='number')),
-                ('title', cms.models.VarCharField(verbose_name='section')),
-                ('content', models.TextField(blank=True, verbose_name='content')),
-                ('image', models.ImageField(blank=True, upload_to='', verbose_name='image')),
-                ('video', embed_video.fields.EmbedVideoField(blank=True, help_text='Paste a YouTube, Vimeo, or SoundCloud link', verbose_name='video')),
-                ('href', cms.models.VarCharField(blank=True, verbose_name='link')),
-                ('page', models.ForeignKey(on_delete=django.db.models.deletion.PROTECT, related_name='sections', to=settings.CMS_PAGE_MODEL, verbose_name='page')),
-                ('polymorphic_ctype', models.ForeignKey(editable=False, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='polymorphic_cms.section_set+', to='contenttypes.ContentType')),
-            ],
-            options={
-                'verbose_name': 'section',
-                'verbose_name_plural': 'sections',
-                'ordering': ['number'],
-                'abstract': False,
-                'swappable': 'CMS_SECTION_MODEL',
-            },
-            bases=(cms.models.Numbered, models.Model),
-        ),
-    ]

cms/migrations/0003_remove_section_polymorphic_ctype.py

@@ -1,17 +0,0 @@
-# Generated by Django 3.0.3 on 2020-03-21 10:23
-
-from django.db import migrations
-
-
-class Migration(migrations.Migration):
-
-    dependencies = [
-        ('cms', '0002_initial_homepage'),
-    ]
-
-    operations = [
-        migrations.RemoveField(
-            model_name='section',
-            name='polymorphic_ctype',
-        ),
-    ]

cms/models.py

@@ -1,5 +1,3 @@
-import swapper
-
 from django.db import models
 from django.urls import reverse
 from django.utils.text import slugify
@@ -89,16 +87,10 @@ class BasePage(Numbered, models.Model):
 
 class BaseSection(Numbered, models.Model):
     '''Abstract base model for sections'''
-
-    # These will be populated by @register
     TYPES = []
-    _cms_views = {}
-
-    page = models.ForeignKey(swapper.get_model_name('cms', 'Page'), verbose_name=_('page'), related_name='sections', on_delete=models.PROTECT)
     title = VarCharField(_('section'))
     type = VarCharField(_('type'))
     number = models.PositiveIntegerField(_('number'), blank=True)
-
     content = models.TextField(_('content'), blank=True)
     image = models.ImageField(_('image'), blank=True)
     video = EmbedVideoField(_('video'), blank=True, help_text=_('Paste a YouTube, Vimeo, or SoundCloud link'))
@@ -118,33 +110,8 @@ class BaseSection(Numbered, models.Model):
         else:
             return self.title
 
-    def get_view(self, request):
-        '''Try to instantiate the registered view for this section'''
-        try:
-            return self.__class__._cms_views[self.type](request)
-        except:
-            raise ImproperlyConfigured(
-                f'No view registered for sections of type {self.type}!')
-
-    @classmethod
-    def get_fields_per_type(cls):
-        fields_per_type = {}
-        for name, view in cls._cms_views.items():
-            fields_per_type[name] = ['type', 'number'] + view.fields
-        return fields_per_type
-
     class Meta:
         abstract = True
         verbose_name = _('section')
         verbose_name_plural = _('sections')
         ordering = ['number']
-
-class Page(BasePage):
-    '''Swappable page model'''
-    class Meta(BasePage.Meta):
-        swappable = swapper.swappable_setting('cms', 'Page')
-
-class Section(BaseSection):
-    '''Swappable section model'''
-    class Meta(BaseSection.Meta):
-        swappable = swapper.swappable_setting('cms', 'Section')

cms/registry.py

@@ -0,0 +1,13 @@
+views_per_type = {}
+page_class = None
+section_class = None
+
+def get_view(section, request):
+    '''Instantiate the registered view of a section'''
+    return views_per_type[section.type](request)
+
+def get_fields_per_type():
+    fields_per_type = {}
+    for name, view in views_per_type.items():
+        fields_per_type[name] = ['title', 'type', 'number'] + view.fields
+    return fields_per_type

cms/templatetags/cms.py

@@ -5,6 +5,8 @@ from django.shortcuts import reverse
 from django.utils.safestring import mark_safe
 from django.utils.translation import gettext_lazy as _
 
+from cms import registry
+
 MARKDOWN_EXTENSIONS = ['extra', 'smarty']
 register = template.Library()
 
@@ -51,7 +53,7 @@ class IncludeSectionNode(template.Node):
         csrf_token = self.csrf_token.resolve(context)
         request = self.request.resolve(context)
         perms = self.perms.resolve(context)
-        view = section.get_view(request)
+        view = registry.get_view(section, request)
         section_context = view.get_context_data(
             csrf_token=csrf_token,
             section=section,

cms/views.py

@@ -1,19 +1,39 @@
 import json
-import swapper
 
 from django.shortcuts import redirect
 from django.views.generic import base, detail, edit
 from django.contrib.auth.mixins import UserPassesTestMixin
 from django.http import Http404, HttpResponse, HttpResponseRedirect, HttpResponseBadRequest
 
+from . import registry
 from .forms import PageForm, SectionForm
 
-Page = swapper.load_model('cms', 'Page')
-Section = swapper.load_model('cms', 'Section')
+class SectionView:
+    '''Generic section view'''
+    template_name = 'cms/sections/section.html'
+
+    def __init__(self, request):
+        '''Initialize request attribute'''
+        self.request = request
+
+    def get_context_data(self, **kwargs):
+        '''Override this to customize a section's context'''
+        return kwargs
+
+class SectionFormView(edit.FormMixin, SectionView):
+    '''Generic section with associated form'''
+
+    def post(self, request):
+        '''Process form'''
+        form = self.get_form()
+        if form.is_valid():
+            form.save(request)
+            return HttpResponseRedirect(self.get_success_url())
+        return form
 
 class PageView(detail.DetailView):
     '''View of a page with heterogeneous sections'''
-    model = Page
+    model = registry.page_class
     template_name = 'cms/page.html'
 
     def setup(self, *args, slug='', **kwargs):
@@ -25,9 +45,14 @@ class PageView(detail.DetailView):
         try:
             page = self.object = self.get_object()
         except Http404:
-            if self.request.user.has_perm('cms_page_create'):
+            if self.kwargs['slug'] == '':
+                page = registry.page_class(title='Homepage', slug='')
+                page.save()
+                self.object = page
+            elif self.request.user.has_perm('cms_page_create'):
                 return redirect('cms:updatepage', self.kwargs['slug'])
-            raise
+            else:
+                raise
         context = self.get_context_data(**kwargs)
         sections = page.sections.all()
         context.update({
@@ -48,7 +73,7 @@ class PageView(detail.DetailView):
         sections = page.sections.all()
         for section in sections:
             if section.pk == pk:
-                view = section.get_view(request)
+                view = registry.get_view(section, request)
                 result = view.post(request)
                 if isinstance(result, HttpResponse):
                     return result
@@ -62,7 +87,7 @@ class PageView(detail.DetailView):
 
     def get_context_data(self, **kwargs):
         context = super().get_context_data(**kwargs)
-        pages = Page.objects.filter(menu=True)
+        pages = registry.page_class.objects.filter(menu=True)
         context.update({
             'pages': pages,
         })
@@ -70,7 +95,7 @@ class PageView(detail.DetailView):
 
 class EditPage(UserPassesTestMixin, edit.ModelFormMixin, base.TemplateResponseMixin, base.View):
     '''Base view with nested forms for editing the page and all its sections'''
-    model = Page
+    model = registry.page_class
     form_class = PageForm
     template_name = 'cms/edit.html'
 
@@ -88,7 +113,7 @@ class EditPage(UserPassesTestMixin, edit.ModelFormMixin, base.TemplateResponseMi
     def get_context_data(self, **kwargs):
         '''Populate the fields_per_type dict for use in javascript'''
         context = super().get_context_data(**kwargs)
-        context['fields_per_type'] = json.dumps(Section.get_fields_per_type())
+        context['fields_per_type'] = json.dumps(registry.get_fields_per_type())
         return context
 
     def get_object(self):
@@ -118,13 +143,13 @@ class EditPage(UserPassesTestMixin, edit.ModelFormMixin, base.TemplateResponseMi
 class CreatePage(EditPage):
     '''View for creating new pages'''
     def get_object(self):
-        return Page()
+        return registry.page_class()
 
 class UpdatePage(EditPage):
     '''View for editing existing pages'''
 
 class EditSection(UserPassesTestMixin, edit.ModelFormMixin, base.TemplateResponseMixin, base.View):
-    model = Section
+    model = registry.section_class
     form_class = SectionForm
     template_name = 'cms/edit.html'
 
@@ -140,20 +165,20 @@ class EditSection(UserPassesTestMixin, edit.ModelFormMixin, base.TemplateRespons
 
     def get_context_data(self, **kwargs):
         context = super().get_context_data(**kwargs)
-        context['fields_per_type'] = json.dumps(Section.get_fields_per_type())
+        context['fields_per_type'] = json.dumps(registry.get_fields_per_type())
         return context
 
     def get_object(self, queryset=None):
         try:
-            self.page = Page.objects.get(slug=self.kwargs['slug'])
-        except Page.DoesNotExist:
+            self.page = registry.page_class.objects.get(slug=self.kwargs['slug'])
+        except registry.page_class.DoesNotExist:
             raise Http404()
         return self.get_section()
 
     def get_section(self):
         try:
             section = self.page.sections.get(number=self.kwargs['number'])
-        except Section.DoesNotExist:
+        except self.page.sections.DoesNotExist:
             raise Http404()
         return section
 
@@ -177,7 +202,7 @@ class EditSection(UserPassesTestMixin, edit.ModelFormMixin, base.TemplateRespons
 
 class CreateSection(EditSection):
     def get_section(self):
-        return Section(page=self.page)
+        return registry.section_class(page=self.page)
 
 class UpdateSection(EditSection):
     pass

example/app/migrations/0002_sectionimage.py

@@ -1,26 +0,0 @@
-# Generated by Django 3.0.2 on 2020-03-21 16:58
-
-from django.conf import settings
-from django.db import migrations, models
-import django.db.models.deletion
-
-
-class Migration(migrations.Migration):
-
-    dependencies = [
-        ('app', '0001_initial'),
-    ]
-
-    operations = [
-        migrations.CreateModel(
-            name='SectionImage',
-            fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('image', models.ImageField(upload_to='', verbose_name='Image')),
-                ('section', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='images', to=settings.CMS_SECTION_MODEL)),
-            ],
-            options={
-                'ordering': ['pk'],
-            },
-        ),
-    ]

example/cms.py

@@ -1,24 +1,29 @@
-import cms
+from cms.views import SectionView, SectionFormView
+from cms.decorators import section_view
 from cms.forms import ContactForm
 from django.utils.translation import gettext_lazy as _
 
-@cms.register(_('Text'))
-class Text(cms.SectionView):
+@section_view
+class Text(SectionView):
+    verbose_name = _('Text')
     fields = ['title', 'content']
     template_name = 'app/sections/text.html'
 
-@cms.register(_('Images'))
-class Images(cms.SectionView):
+@section_view
+class Images(SectionView):
+    verbose_name = _('Images')
     fields = ['title', 'images']
     template_name = 'app/sections/images.html'
 
-@cms.register(_('Video'))
-class Video(cms.SectionView):
+@section_view
+class Video(SectionView):
+    verbose_name = _('Video')
     fields = ['title', 'video']
     template_name = 'app/sections/video.html'
 
-@cms.register(_('Contact'))
-class Contact(cms.SectionFormView):
+@section_view
+class Contact(SectionFormView):
+    verbose_name = _('Contact')
     fields = ['title']
     form_class = ContactForm
     success_url = '/thanks/'

example/migrations/0001_initial.py

@@ -1,7 +1,6 @@
-# Generated by Django 3.0.2 on 2020-03-21 16:44
+# Generated by Django 3.0.2 on 2020-03-22 11:11
 
 import cms.models
-from django.conf import settings
 from django.db import migrations, models
 import django.db.models.deletion
 import embed_video.fields
@@ -32,6 +31,16 @@ class Migration(migrations.Migration):
             },
             bases=(cms.models.Numbered, models.Model),
         ),
+        migrations.CreateModel(
+            name='SectionImage',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('image', models.ImageField(upload_to='', verbose_name='Image')),
+            ],
+            options={
+                'ordering': ['pk'],
+            },
+        ),
         migrations.CreateModel(
             name='Section',
             fields=[
@@ -43,7 +52,7 @@ class Migration(migrations.Migration):
                 ('image', models.ImageField(blank=True, upload_to='', verbose_name='image')),
                 ('video', embed_video.fields.EmbedVideoField(blank=True, help_text='Paste a YouTube, Vimeo, or SoundCloud link', verbose_name='video')),
                 ('href', cms.models.VarCharField(blank=True, verbose_name='link')),
-                ('page', models.ForeignKey(on_delete=django.db.models.deletion.PROTECT, related_name='sections', to=settings.CMS_PAGE_MODEL, verbose_name='page')),
+                ('page', models.ForeignKey(on_delete=django.db.models.deletion.PROTECT, related_name='sections', to='example.Page', verbose_name='page')),
             ],
             options={
                 'verbose_name': 'section',

example/models.py

@@ -1,21 +1,25 @@
 from django.db import models
-from cms.models import BasePage, BaseSection
 from django.utils.translation import gettext_lazy as _
+from cms.models import BasePage, BaseSection
+from cms.decorators import page_model, section_model
 
+@page_model
 class Page(BasePage):
     '''Add custom fields here. Already existing fields: title, slug,
     number, menu
 
     '''
 
+@section_model
 class Section(BaseSection):
     '''Add custom fields here. Already existing fields: title, type,
     number, content, image, video, href
 
     '''
+    page = models.ForeignKey(Page, verbose_name=_('page'), related_name='sections', on_delete=models.PROTECT)
 
 class SectionImage(models.Model):
-    section = models.ForeignKey(Section, related_name='images', on_delete=models.CASCADE)
+    #section = models.ForeignKey(Section, related_name='images', on_delete=models.CASCADE)
     image = models.ImageField(_('Image'))
 
     class Meta:

example/settings.py

@@ -1,19 +1,13 @@
 import os, random, string
-try:
-    import uwsgi
-    DEBUG = False
-except ImportError:
-    DEBUG = True
-    EMAIL_BACKEND = 'django.core.mail.backends.console.EmailBackend'
 
-PROJECT_NAME = 'example'
+PROJECT_NAME = os.path.basename(os.path.dirname(os.path.abspath(__file__)))
 KEYFILE = f'/tmp/{PROJECT_NAME}.secret'
 ADMINS = [('JJ Vens', 'jj@rtts.eu')]
 DEFAULT_FROM_EMAIL = 'noreply@rtts.eu'
 DEFAULT_TO_EMAIL = 'jj@rtts.eu'
 ALLOWED_HOSTS = ['*']
-ROOT_URLCONF = 'project.urls'
-WSGI_APPLICATION = 'project.wsgi.application'
+ROOT_URLCONF = PROJECT_NAME + '.urls'
+WSGI_APPLICATION = PROJECT_NAME + '.wsgi.application'
 LANGUAGE_CODE = 'nl'
 TIME_ZONE = 'Europe/Amsterdam'
 USE_I18N = True
@@ -24,8 +18,13 @@ STATIC_ROOT = '/srv/' + PROJECT_NAME + '/static'
 MEDIA_URL = '/media/'
 MEDIA_ROOT = '/srv/' + PROJECT_NAME + '/media'
 LOGIN_REDIRECT_URL = '/'
-CMS_SECTION_MODEL = 'app.Section'
-CMS_PAGE_MODEL = 'app.Page'
+
+try:
+    import uwsgi
+    DEBUG = False
+except ImportError:
+    DEBUG = True
+    EMAIL_BACKEND = 'django.core.mail.backends.console.EmailBackend'
 
 def read(file):
     with open(file) as f:
@@ -40,7 +39,7 @@ except IOError:
     write(KEYFILE, SECRET_KEY)
 
 INSTALLED_APPS = [
-    'app',
+    PROJECT_NAME,
     'django.contrib.admin',
     'django.contrib.auth',
     'django.contrib.contenttypes',

manage.py

@@ -3,7 +3,7 @@ import os
 import sys
 
 if __name__ == '__main__':
-    os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'project.settings')
+    os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'example.settings')
     try:
         from django.core.management import execute_from_command_line
     except ImportError as exc:

setup.py

@@ -3,7 +3,7 @@ from setuptools import setup, find_packages
 
 setup(
     name = 'django-simplecms',
-    version = '2.3.1',
+    version = '3.0.0',
     url = 'https://github.com/rtts/django-simplecms',
     author = 'Jaap Joris Vens',
     author_email = 'jj@rtts.eu',
@@ -15,11 +15,9 @@ setup(
         'django',
         'django-extensions',
         'django-embed-video',
-        'django-polymorphic',
         'easy-thumbnails',
         'psycopg2',
         'markdown',
         'libsass',
-        'swapper',
     ],
 )