From 4d6de7cca540e95b4355cfbc14d068ee2e5b577b Mon Sep 17 00:00:00 2001
From: melinath <stephen.r.burrows@gmail.com>
Date: Thu, 10 Jun 2010 18:02:52 -0400
Subject: [PATCH] Added admin form validation to prevent: 1. a treemodel being
 its own parent (uses a validate_parents method added to the model.) 2. a node
 having the same path (i.e. parent+slug) as another Also added a ModelAdmin
 for the File model.

---
 admin.py  | 45 +++++++++++++++++++++++++++++++++++++++++++--
 models.py | 35 +++++++++++++++++++++++++++++++++--
 2 files changed, 76 insertions(+), 4 deletions(-)

diff --git a/admin.py b/admin.py
index 73dea0a..f63b576 100644
--- a/admin.py
+++ b/admin.py
@@ -8,6 +8,7 @@ from django.utils.safestring import mark_safe
 from django.utils.html import escape
 from django.utils.text import truncate_words
 from models import *
+from django.core.exceptions import ValidationError, ObjectDoesNotExist
 
 
 class AttributeInline(generic.GenericTabularInline):
@@ -94,6 +95,40 @@ class ModelLookupWidget(forms.TextInput):
 				pass
 		return mark_safe(output)
 
+class NodeForm(forms.ModelForm):
+	
+	def __init__(self, *args, **kwargs):
+		super(NodeForm, self).__init__(*args, **kwargs)
+		instance = self.instance
+		try:
+			self.fields['parent'].queryset = instance.node_ptr.__class__.objects.exclude(id=instance.id)
+		except ObjectDoesNotExist:
+			pass
+	
+	def clean(self):
+		cleaned_data = self.cleaned_data
+		parent = self.cleaned_data['parent']
+		self.instance.validate_parents(parent)
+			
+		try:
+			Node.objects.get(slug=self.cleaned_data['slug'], parent=parent)
+			raise ValidationError("A node with that path (parent and slug) already exists.")
+		except ObjectDoesNotExist:
+			pass
+		
+		return cleaned_data
+
+class PageAdminForm(NodeForm):
+	class Meta:
+		model=Page
+
+class RedirectAdminForm(NodeForm):
+	class Meta:
+		model=Redirect
+		
+class FileAdminForm(NodeForm):
+	class Meta:
+		model=File
 
 class PageAdmin(EntityAdmin):
 	prepopulated_fields = {'slug': ('title',)}
@@ -109,6 +144,7 @@ class PageAdmin(EntityAdmin):
 	list_display = ('title', 'path', 'template')
 	list_filter = ('template',)
 	search_fields = ['title', 'slug', 'contentlets__content']
+	form = PageAdminForm
 	
 	def get_fieldsets(self, request, obj=None, **kwargs):
 		fieldsets = list(self.fieldsets)
@@ -174,11 +210,16 @@ class PageAdmin(EntityAdmin):
 					contentreference.save()
 
 class RedirectAdmin(admin.ModelAdmin):
-	list_display=('slug', 'target', 'status_code',)
+	list_display=('slug', 'target', 'path', 'status_code',)
 	list_filter=('status_code',)
+	form = RedirectAdminForm
+
+class FileAdmin(admin.ModelAdmin):
+	form=FileAdminForm
+	list_display=('slug', 'mimetype', 'path', 'file',)
 
 admin.site.register(Collection, CollectionAdmin)
 admin.site.register(Redirect, RedirectAdmin)
-admin.site.register(File)
+admin.site.register(File, FileAdmin)
 admin.site.register(Page, PageAdmin)
 admin.site.register(Template, TemplateAdmin)
diff --git a/models.py b/models.py
index 6eac9de..878d3d4 100644
--- a/models.py
+++ b/models.py
@@ -10,7 +10,7 @@ from django.template import add_to_builtins as register_templatetags
 from django.template import Template as DjangoTemplate
 from django.template import TemplateDoesNotExist
 from django.template import Context, RequestContext
-from django.core.exceptions import ObjectDoesNotExist
+from django.core.exceptions import ObjectDoesNotExist, ValidationError
 try:
 	import json
 except ImportError:
@@ -157,7 +157,6 @@ class TreeManager(models.Manager):
 				return (obj, remainder)
 		raise self.model.DoesNotExist('%s matching query does not exist.' % self.model._meta.object_name)
 
-
 class TreeModel(models.Model):
 	objects = TreeManager()
 	parent = models.ForeignKey('self', related_name='children', null=True, blank=True)
@@ -167,6 +166,7 @@ class TreeModel(models.Model):
 		path = getattr(self, field, '?')
 		parent = self.parent
 		while parent:
+			self.validate_parent(parent)
 			path = getattr(parent, field, '?') + pathsep + path
 			parent = parent.parent
 		return path
@@ -177,6 +177,30 @@ class TreeModel(models.Model):
 	
 	class Meta:
 		abstract = True
+		
+	def validate_parents(self, parent=None):
+		if parent == None:
+			parent = self.parent
+		
+		while parent:
+			try:
+				self.validate_parent(parent)
+				parent = parent.parent
+			except ObjectDoesNotExist:
+				return # because it likely means the child doesn't exist 
+			
+	def validate_parent(self, parent):
+		#Why doesn't this stop the Admin site from saving a model with itself as parent?
+		if self == parent:
+			raise ValidationError("A %s can't be its own parent." % self.__class__.__name__)
+	
+	def clean(self):
+		super(TreeModel, self).clean()
+		self.validate_parents()
+	
+	def save(self, *args, **kwargs):
+		self.clean()
+		super(TreeModel, self).save(*args, **kwargs)
 
 
 class TreeEntity(TreeModel, Entity):
@@ -207,6 +231,10 @@ class InheritableTreeEntity(TreeEntity):
 	@property
 	def instance(self):
 		return self.instance_type.get_object_for_this_type(id=self.id)
+		
+	def validate_parent(self, parent):
+		if self.instance == parent.instance:
+			raise ValidationError("A %s can't be its own parent." % self.__class__.__name__)
 	
 	def get_path(self, pathsep='/', field='slug'):
 		path = getattr(self.instance, field, '?')
@@ -238,6 +266,9 @@ class Node(InheritableTreeEntity):
 	
 	def render_to_response(self, request, path=None, subpath=None):
 		return HttpResponseServerError()
+		
+	class Meta:
+		unique_together=(('parent', 'slug',),)
 
 
 class MultiNode(Node):
-- 
2.20.1