Remove .related many to many relationship, it's not really useful

since we always have to restrict on the relationship type anyway,
instead add two helpers for doing the necessary queries (in both
directions)
 - Legacy-Id: 5205

ietf/doc/admin.py

@@ -93,7 +93,7 @@ class DocumentAdmin(admin.ModelAdmin):
     list_display = ['name', 'rev', 'group', 'pages', 'intended_std_level', 'author_list', 'time']
     search_fields = ['name']
     list_filter = ['type']
-    raw_id_fields = ['authors', 'related', 'group', 'shepherd', 'ad']
+    raw_id_fields = ['authors', 'group', 'shepherd', 'ad']
     inlines = [DocAliasInline, DocAuthorInline, RelatedDocumentInline, ]
     form = DocumentForm
 

ietf/doc/models.py

@@ -4,6 +4,7 @@ from django.db import models
 from django.core.urlresolvers import reverse as urlreverse
 from django.contrib.contenttypes.models import ContentType
 from django.conf import settings
+from django.utils.html import mark_safe
 
 from ietf.group.models import *
 from ietf.name.models import *
@@ -168,7 +169,7 @@ class DocumentAuthor(models.Model):
     
 class Document(DocumentInfo):
     name = models.CharField(max_length=255, primary_key=True)           # immutable
-    related = models.ManyToManyField('DocAlias', through=RelatedDocument, blank=True, related_name="reversely_related_document_set")
+    #related = models.ManyToManyField('DocAlias', through=RelatedDocument, blank=True, related_name="reversely_related_document_set")
     authors = models.ManyToManyField(Email, through=DocumentAuthor, blank=True)
 
     def __unicode__(self):
@@ -231,6 +232,14 @@ class Document(DocumentInfo):
             name = name.upper()
         return name
 
+    def related_that(self, relationship):
+        """Return the documents that are source of relationship targeting self."""
+        return Document.objects.filter(relateddocument__target__document=self, relateddocument__relationship=relationship)
+
+    def related_that_doc(self, relationship):
+        """Return the doc aliases that are target of relationship originating from self."""
+        return DocAlias.objects.filter(relateddocument__source=self, relateddocument__relationship=relationship)
+
     #TODO can/should this be a function instead of a property? Currently a view uses it as a property
     @property
     def telechat_date(self):
@@ -285,9 +294,6 @@ class Document(DocumentInfo):
         qs = self.docalias_set.filter(name__startswith='rfc')
         return qs[0].name[3:] if qs else None
 
-    def replaced_by(self):
-        return [ rel.source for alias in self.docalias_set.all() for rel in alias.relateddocument_set.filter(relationship='replaces') ]
-
     def friendly_state(self):
         """ Return a concise text description of the document's current state """
         if self.type_id=='draft':
@@ -306,11 +312,12 @@ class Document(DocumentInfo):
                      iesg_state_summary = iesg_state_summary + "::"+"::".join(tag.name for tag in iesg_substate)
              
             if self.get_state_slug() == "rfc":
-                return "<a href=\"%s\">RFC %d</a>" % (urlreverse('doc_view', args=['rfc%d' % self.rfc_number]), self.rfc_number)
+                n = self.rfc_number()
+                return "<a href=\"%s\">RFC %s</a>" % (urlreverse('doc_view', kwargs=dict(name='rfc%s' % n)), n)
             elif self.get_state_slug() == "repl":
-                rs = self.replaced_by()
+                rs = self.related_that("replaces")
                 if rs:
-                    return "Replaced by "+", ".join("<a href=\"%s\">%s</a>" % (urlreverse('doc_view', args=[name]),name) for name in rs)
+                    return mark_safe("Replaced by " + ", ".join("<a href=\"%s\">%s</a>" % (urlreverse('doc_view', args=[name]), name) for name in rs))
                 else:
                     return "Replaced"
             elif self.get_state_slug() == "active":