edit route descriptions: only suggest neighbor spaces

src/c3nav/editor/forms.py

@@ -1,8 +1,11 @@
 import json
 import operator
 from functools import reduce
+from itertools import chain
 
+from django.core.cache import cache
 from django.core.exceptions import FieldDoesNotExist
+from django.db.models import Q
 from django.forms import (BooleanField, CharField, ChoiceField, Form, ModelChoiceField, ModelForm, MultipleChoiceField,
                           ValidationError)
 from django.forms.widgets import HiddenInput
@@ -13,10 +16,11 @@ from c3nav.editor.models import ChangeSet, ChangeSetUpdate
 from c3nav.mapdata.fields import GeometryField
 from c3nav.mapdata.forms import I18nModelFormMixin
 from c3nav.mapdata.models import GraphEdge
+from c3nav.mapdata.models.access import AccessPermission
 
 
 class EditorFormBase(I18nModelFormMixin, ModelForm):
-    def __init__(self, *args, request=None, **kwargs):
+    def __init__(self, *args, space_id=None, request=None, **kwargs):
         self.request = request
         super().__init__(*args, **kwargs)
         creating = not self.instance.pk
@@ -71,9 +75,36 @@ class EditorFormBase(I18nModelFormMixin, ModelForm):
             self.fields['access_restriction'].label_from_instance = lambda obj: obj.title
             self.fields['access_restriction'].queryset = AccessRestriction.qs_for_request(self.request)
 
-        if 'target_space' in self.fields:
+        if space_id and 'target_space' in self.fields:
             Space = self.request.changeset.wrap_model('Space')
-            space_qs = Space.qs_for_request(self.request)
+
+            GraphNode = self.request.changeset.wrap_model('GraphNode')
+            GraphEdge = self.request.changeset.wrap_model('GraphEdge')
+
+            cache_key = 'editor:neighbor_spaces:%s:%s%d' % (
+                self.request.changeset.raw_cache_key_by_changes,
+                AccessPermission.cache_key_for_request(request, with_update=False),
+                space_id
+            )
+            other_spaces = cache.get(cache_key, None)
+            if other_spaces is None:
+                AccessPermission.cache_key_for_request(request, with_update=False) + ':' + str(request.user.pk or 0)
+                space_nodes = set(GraphNode.objects.filter(space_id=space_id).values_list('pk', flat=True))
+                space_edges = GraphEdge.objects.filter(
+                    Q(from_node_id__in=space_nodes) | Q(to_node_id__in=space_nodes)
+                ).values_list('from_node_id', 'to_node_id')
+                other_nodes = set(chain(*space_edges)) - space_nodes
+                other_spaces = set(GraphNode.objects.filter(pk__in=other_nodes).values_list('space_id', flat=True))
+                other_spaces.discard(space_id)
+                cache.set(cache_key, other_spaces, 900)
+
+            for space_field in ('origin_space', 'target_space'):
+                other_space_id = getattr(self.instance, space_field+'_id', None)
+                if other_space_id:
+                    other_spaces.add(other_space_id)
+
+            space_qs = Space.qs_for_request(self.request).filter(pk__in=other_spaces)
+
             for space_field in ('origin_space', 'target_space'):
                 if space_field in self.fields:
                     self.fields[space_field].label_from_instance = lambda obj: obj.title

src/c3nav/editor/views/edit.py

@@ -142,6 +142,7 @@ def edit(request, pk=None, model=None, level=None, space=None, on_top_of=None, e
             'geomtype': model._meta.get_field('geometry').geomtype,
         })
 
+    space_id = None
     if model == Level:
         ctx.update({
             'level': obj,
@@ -183,6 +184,7 @@ def edit(request, pk=None, model=None, level=None, space=None, on_top_of=None, e
             'geometry_url': '/api/editor/geometries/?level='+str(level.primary_level_pk),
         })
     elif hasattr(model, 'space'):
+        space_id = space.pk
         if not new:
             space = obj.space
         ctx.update({
@@ -234,7 +236,8 @@ def edit(request, pk=None, model=None, level=None, space=None, on_top_of=None, e
             ctx['obj_title'] = obj.title
             return render(request, 'editor/delete.html', ctx)
 
-        form = model.EditorForm(instance=model() if new else obj, data=request.POST, request=request)
+        form = model.EditorForm(instance=model() if new else obj, data=request.POST,
+                                request=request, space_id=space_id)
         if form.is_valid():
             # Update/create objects
             obj = form.save(commit=False)
@@ -266,7 +269,7 @@ def edit(request, pk=None, model=None, level=None, space=None, on_top_of=None, e
                     messages.error(request, _('You can not edit changes on this changeset.'))
 
     else:
-        form = model.EditorForm(instance=obj, request=request)
+        form = model.EditorForm(instance=obj, request=request, space_id=space_id)
 
     ctx.update({
         'form': form,
@@ -319,12 +322,28 @@ def list_objects(request, model=None, level=None, space=None, explicit_edit=Fals
         sub_qs = Space.objects.filter(Space.q_for_request(request)).select_related('level').defer('geometry')
         space = get_object_or_404(sub_qs, pk=space)
         queryset = queryset.filter(space=space)
+
         try:
             model._meta.get_field('geometry')
         except FieldDoesNotExist:
             pass
         else:
             queryset = queryset.defer('geometry')
+
+        try:
+            model._meta.get_field('origin_space')
+        except FieldDoesNotExist:
+            pass
+        else:
+            queryset = queryset.select_related('origin_space')
+
+        try:
+            model._meta.get_field('target_space')
+        except FieldDoesNotExist:
+            pass
+        else:
+            queryset = queryset.select_related('target_space')
+
         ctx.update({
             'levels': Level.objects.filter(Level.q_for_request(request), on_top_of__isnull=True),
             'level': space.level,