Remove remaining Django 1.7 code and deprecate wagtail.utils.compat functions

wagtail/contrib/wagtailapi/serializers.py

@@ -10,7 +10,6 @@ from rest_framework import serializers
 from rest_framework.fields import Field
 from rest_framework import relations
 
-from wagtail.utils.compat import get_related_model
 from wagtail.wagtailcore import fields as wagtailcore_fields
 
 from .utils import get_full_url, pages_for_site
@@ -265,7 +264,7 @@ class PageSerializer(BaseSerializer):
         if relation_info.to_many:
             model = getattr(self.Meta, 'model')
             child_relations = {
-                child_relation.field.rel.related_name: get_related_model(child_relation)
+                child_relation.field.rel.related_name: child_relation.related_model
                 for child_relation in get_all_child_relations(model)
             }
 

wagtail/utils/compat.py

@@ -1,40 +1,37 @@
-import django
+import warnings
+
 from django.template import loader
 
+from wagtail.utils.deprecation import RemovedInWagtail16Warning
+
 
 def get_related_model(rel):
-    # In Django 1.7 and under, the related model is accessed by doing: rel.model
-    # This was renamed in Django 1.8 to rel.related_model. rel.model now returns
-    # the base model.
-    if django.VERSION >= (1, 8):
-        return rel.related_model
-    else:
-        return rel.model
+    warnings.warn(
+        'wagtail.utils.compat.get_related_model(rel) is deprecated. '
+        'Use rel.related_model instead',
+        RemovedInWagtail16Warning, stacklevel=2
+    )
+    return rel.related_model
 
 
 def get_related_parent_model(rel):
-    # In Django 1.7 and under, the parent model is accessed by doing: rel.parent_model
-    # This was renamed in Django 1.8 to rel.model.
-    if django.VERSION >= (1, 8):
-        return rel.model
-    else:
-        return rel.parent_model
+    warnings.warn(
+        'wagtail.utils.compat.get_related_parent_model(rel) is deprecated. '
+        'Use rel.model instead',
+        RemovedInWagtail16Warning, stacklevel=2
+    )
+    return rel.model
 
 
 def render_to_string(template_name, context=None, request=None, **kwargs):
-    if django.VERSION >= (1, 8):
-        return loader.render_to_string(
-            template_name,
-            context=context,
-            request=request,
-            **kwargs
-        )
-    else:
-        # Backwards compatibility for Django 1.7 and below
-        from django.template.context import RequestContext
-        return loader.render_to_string(
-            template_name,
-            dictionary=context,
-            context_instance=RequestContext(request),
-            **kwargs
-        )
+    warnings.warn(
+        'wagtail.utils.compat.render_to_string is deprecated. '
+        'Use django.template.loader.render_to_string instead',
+        RemovedInWagtail16Warning, stacklevel=2
+    )
+    return loader.render_to_string(
+        template_name,
+        context=context,
+        request=request,
+        **kwargs
+    )

wagtail/wagtailadmin/edit_handlers.py

@@ -20,7 +20,6 @@ from taggit.managers import TaggableManager
 from wagtail.wagtailadmin import widgets
 from wagtail.wagtailcore.models import Page
 from wagtail.wagtailcore.utils import camelcase_to_underscore, resolve_model_string
-from wagtail.utils.compat import get_related_model, get_related_parent_model
 
 
 # Form field properties to override whenever we encounter a model field
@@ -526,7 +525,7 @@ class BaseChooserPanel(BaseFieldPanel):
 
     def get_chosen_item(self):
         field = self.instance._meta.get_field(self.field_name)
-        related_model = get_related_parent_model(field.related)
+        related_model = field.related.model
         try:
             return getattr(self.instance, self.field_name)
         except related_model.DoesNotExist:
@@ -617,7 +616,7 @@ class BaseInlinePanel(EditHandler):
         # Failing that, get it from the model
         else:
             return extract_panel_definitions_from_model_class(
-                get_related_model(cls.related),
+                cls.related.related_model,
                 exclude=[cls.related.field.name]
             )
 
@@ -630,7 +629,7 @@ class BaseInlinePanel(EditHandler):
             cls._child_edit_handler_class = MultiFieldPanel(
                 panels,
                 heading=cls.heading
-            ).bind_to_model(get_related_model(cls.related))
+            ).bind_to_model(cls.related.related_model)
 
         return cls._child_edit_handler_class
 

wagtail/wagtailadmin/menu.py

@@ -2,13 +2,11 @@ from __future__ import unicode_literals
 
 from django.forms import MediaDefiningClass, Media
 from django.forms.utils import flatatt
+from django.template.loader import render_to_string
 from django.utils.text import slugify
 from django.utils.safestring import mark_safe
-from django.utils.six import text_type
+from django.utils.six import text_type, with_metaclass
 
-from django.utils.six import with_metaclass
-
-from wagtail.utils.compat import render_to_string
 from wagtail.wagtailcore import hooks
 
 

wagtail/wagtailadmin/modal_workflow.py

@@ -1,8 +1,7 @@
 import json
 
 from django.http import HttpResponse
-
-from wagtail.utils.compat import render_to_string
+from django.template.loader import render_to_string
 
 
 def render_modal_workflow(request, html_template, js_template, template_vars=None):

wagtail/wagtailadmin/search.py

@@ -2,6 +2,7 @@ from __future__ import unicode_literals
 
 from django.forms import MediaDefiningClass, Media
 from django.forms.utils import flatatt
+from django.template.loader import render_to_string
 from django.utils.text import slugify
 from django.utils.safestring import mark_safe
 from django.utils.six import text_type
@@ -9,7 +10,6 @@ from django.utils.functional import cached_property, total_ordering
 
 from django.utils.six import with_metaclass
 
-from wagtail.utils.compat import render_to_string
 from wagtail.wagtailcore import hooks
 from wagtail.wagtailadmin.forms import SearchForm
 

wagtail/wagtailadmin/site_summary.py

@@ -1,6 +1,7 @@
+from django.template.loader import render_to_string
+
 from wagtail.wagtailcore import hooks
 from wagtail.wagtailcore.models import Page, Site
-from wagtail.utils.compat import render_to_string
 
 
 class SummaryItem(object):

wagtail/wagtailadmin/userbar.py

@@ -1,4 +1,4 @@
-from wagtail.utils.compat import render_to_string
+from django.template.loader import render_to_string
 
 
 class BaseItem(object):

wagtail/wagtailadmin/utils.py

@@ -12,7 +12,6 @@ from modelcluster.fields import ParentalKey
 
 from wagtail.wagtailcore.models import Page, PageRevision, GroupPagePermission
 from wagtail.wagtailusers.models import UserProfile
-from wagtail.utils.compat import get_related_model
 
 
 def get_object_usage(obj):
@@ -26,7 +25,7 @@ def get_object_usage(obj):
         include_proxy_eq=True
     )
     for relation in relations:
-        related_model = get_related_model(relation)
+        related_model = relation.related_model
 
         # if the relation is between obj and a page, get the page
         if issubclass(related_model, Page):

wagtail/wagtailadmin/views/home.py

@@ -1,10 +1,10 @@
 from django.shortcuts import render
 from django.conf import settings
 from django.db.models import F
+from django.template.loader import render_to_string
 
 from wagtail.wagtailcore import hooks
 from wagtail.wagtailcore.models import PageRevision, UserPagePermissionsProxy
-from wagtail.utils.compat import render_to_string
 
 from wagtail.wagtailadmin.site_summary import SiteSummaryPanel
 

wagtail/wagtailcore/models.py

@@ -7,7 +7,6 @@ import warnings
 
 from collections import defaultdict
 from modelcluster.models import ClusterableModel, get_all_child_relations
-import django
 from django.db import models, connection, transaction
 from django.db.models import Q
 from django.db.models.signals import post_save, pre_delete, post_delete
@@ -941,31 +940,25 @@ class Page(six.with_metaclass(PageBase, MP_Node, ClusterableModel, index.Indexed
         specific_self = self.specific
         specific_dict = {}
 
-        if django.VERSION >= (1, 8):
-            for field in specific_self._meta.get_fields():
-                # Ignore explicitly excluded fields
-                if field.name in exclude_fields:
-                    continue
+        for field in specific_self._meta.get_fields():
+            # Ignore explicitly excluded fields
+            if field.name in exclude_fields:
+                continue
 
-                # Ignore reverse relations
-                if field.auto_created:
-                    continue
+            # Ignore reverse relations
+            if field.auto_created:
+                continue
 
-                # Ignore m2m relations - they will be copied as child objects
-                # if modelcluster supports them at all (as it does for tags)
-                if field.many_to_many:
-                    continue
+            # Ignore m2m relations - they will be copied as child objects
+            # if modelcluster supports them at all (as it does for tags)
+            if field.many_to_many:
+                continue
 
-                # Ignore parent links (page_ptr)
-                if isinstance(field, models.OneToOneField) and field.parent_link:
-                    continue
+            # Ignore parent links (page_ptr)
+            if isinstance(field, models.OneToOneField) and field.parent_link:
+                continue
 
-                specific_dict[field.name] = getattr(specific_self, field.name)
-        else:
-            # Django 1.7
-            for field in specific_self._meta.fields:
-                if field.name not in exclude_fields and not (field.rel is not None and field.rel.parent_link):
-                    specific_dict[field.name] = getattr(specific_self, field.name)
+            specific_dict[field.name] = getattr(specific_self, field.name)
 
         # New instance from prepared dict values, in case the instance class implements multiple levels inheritance
         page_copy = self.specific_class(**specific_dict)

wagtail/wagtailimages/models.py

@@ -33,7 +33,6 @@ from wagtail.wagtailsearch.queryset import SearchableQuerySetMixin
 from wagtail.wagtailimages.rect import Rect
 from wagtail.wagtailimages.exceptions import InvalidFilterSpecError
 from wagtail.wagtailadmin.utils import get_object_usage
-from wagtail.utils.compat import get_related_model
 
 
 class SourceImageIOError(IOError):
@@ -231,9 +230,9 @@ class AbstractImage(models.Model, TagSearchable):
     def get_rendition_model(cls):
         """ Get the Rendition model for this Image model """
         if django.VERSION >= (1, 9):
-            return get_related_model(cls.renditions.rel)
+            return cls.renditions.rel.related_model
         else:
-            return get_related_model(cls.renditions.related)
+            return cls.renditions.related.related_model
 
     def get_rendition(self, filter):
         if isinstance(filter, string_types):

wagtail/wagtailimages/views/multiple.py

@@ -3,6 +3,7 @@ from django.views.decorators.http import require_POST
 from django.core.exceptions import PermissionDenied
 from django.views.decorators.vary import vary_on_headers
 from django.http import JsonResponse, HttpResponseBadRequest
+from django.template.loader import render_to_string
 from django.utils.encoding import force_text
 
 from wagtail.wagtailadmin.utils import permission_required
@@ -12,7 +13,6 @@ from wagtail.wagtailsearch.backends import get_search_backends
 from wagtail.wagtailimages.models import get_image_model
 from wagtail.wagtailimages.forms import get_image_form
 from wagtail.wagtailimages.fields import ALLOWED_EXTENSIONS
-from wagtail.utils.compat import render_to_string
 
 
 def get_image_edit_form(ImageModel):

wagtail/wagtailsearch/index.py

@@ -1,4 +1,3 @@
-import django
 from django.db import models
 from django.db.models.fields import FieldDoesNotExist
 from django.db.models.fields.related import RelatedField, ForeignObjectRel, OneToOneRel
@@ -173,8 +172,6 @@ class RelatedFields(object):
         It decides which method to call based on the number of related objects:
          - single (eg ForeignKey, OneToOne), it runs select_related
          - multiple (eg ManyToMany, reverse ForeignKey) it runs prefetch_related
-
-        This optimisation currently doesn't support reverse relations on Django 1.7.
         """
         try:
             field = self.get_field(queryset.model)
@@ -182,20 +179,10 @@ class RelatedFields(object):
             return queryset
 
         if isinstance(field, RelatedField):
-            if django.VERSION >= (1, 8):
-                if field.many_to_one or field.one_to_one:
-                    queryset = queryset.select_related(self.field_name)
-                elif field.one_to_many or field.many_to_many:
-                    queryset = queryset.prefetch_related(self.field_name)
-            else:
-                from django.db.models.fields.related import ForeignKey
-
-                if isinstance(field, ForeignKey):
-                    # select_related for ForeignKey and OneToOneField
-                    queryset = queryset.select_related(self.field_name)
-                else:
-                    # prefetch_related for anything else (ManyToManyField, tags)
-                    queryset = queryset.prefetch_related(self.field_name)
+            if field.many_to_one or field.one_to_one:
+                queryset = queryset.select_related(self.field_name)
+            elif field.one_to_many or field.many_to_many:
+                queryset = queryset.prefetch_related(self.field_name)
 
         elif isinstance(field, ForeignObjectRel):
             # Reverse relation