optimize traffic for editor geometries / cache objects locally

src/c3nav/editor/api.py

@@ -1,3 +1,4 @@
+from functools import wraps
 from itertools import chain
 
 from django.db.models import Prefetch, Q
@@ -31,6 +32,29 @@ class EditorViewSetMixin(ViewSet):
         return super().initial(request, *args, **kwargs)
 
 
+def api_etag_with_update_cache_key(**outkwargs):
+    outkwargs.setdefault('cache_kwargs', {})['update_cache_key_match'] = bool
+
+    def wrapper(func):
+        func = api_etag(**outkwargs)(func)
+
+        @wraps(func)
+        def wrapped_func(self, request, *args, **kwargs):
+            try:
+                changeset = request.changeset
+            except AttributeError:
+                changeset = ChangeSet.get_for_request(request)
+                request.changeset = changeset
+
+            update_cache_key = request.changeset.raw_cache_key_without_changes
+            update_cache_key_match = request.GET.get('update_cache_key') == update_cache_key
+            return func(self, request, *args,
+                        update_cache_key=update_cache_key, update_cache_key_match=update_cache_key_match,
+                        **kwargs)
+        return wrapped_func
+    return wrapper
+
+
 class EditorViewSet(EditorViewSetMixin, ViewSet):
     """
     Editor API
@@ -103,8 +127,8 @@ class EditorViewSet(EditorViewSetMixin, ViewSet):
 
     # noinspection PyPep8Naming
     @action(detail=False, methods=['get'])
-    @api_etag(etag_func=etag_func, cache_parameters={'level': str, 'space': str})
-    def geometries(self, request, *args, **kwargs):
+    @api_etag_with_update_cache_key(etag_func=etag_func, cache_parameters={'level': str, 'space': str})
+    def geometries(self, request, update_cache_key, update_cache_key_match, *args, **kwargs):
         Level = request.changeset.wrap_model('Level')
         Space = request.changeset.wrap_model('Space')
         Column = request.changeset.wrap_model('Column')
@@ -180,8 +204,6 @@ class EditorViewSet(EditorViewSetMixin, ViewSet):
                 # graphedges,
                 # graphnodes,
             )
-
-            return Response([obj.to_geojson(instance=obj) for obj in results])
         elif space is not None:
             space_q_for_request = Space.q_for_request(request)
             qs = Space.objects.filter(space_q_for_request)
@@ -295,10 +317,21 @@ class EditorViewSet(EditorViewSetMixin, ViewSet):
                 graphedges,
                 graphnodes
             )
-            return Response([obj.to_geojson(instance=obj) for obj in results])
         else:
             raise ValidationError('No level or space specified.')
 
+        return Response({
+            'update_cache_key': update_cache_key,
+            'geometries': [
+                (
+                    obj.get_geojson_key()
+                    if update_cache_key_match and not obj._affected_by_changeset
+                    else obj.to_geojson(instance=obj)
+                )
+                for obj in results
+            ],
+        })
+
     @action(detail=False, methods=['get'])
     @api_etag(etag_func=MapUpdate.current_cache_key, cache_parameters={})
     def geometrystyles(self, request, *args, **kwargs):

src/c3nav/editor/models/changeset.py

@@ -799,6 +799,12 @@ class ChangeSet(models.Model):
     def cache_key_by_changes(self):
         return 'editor:changeset:' + self.raw_cache_key_by_changes
 
+    @property
+    def raw_cache_key_without_changes(self):
+        if self.pk is None:
+            return MapUpdate.current_cache_key()
+        return ':'.join((str(self.pk), MapUpdate.current_cache_key()))
+
     @property
     def raw_cache_key_by_changes(self):
         if self.pk is None:

src/c3nav/editor/static/editor/js/editor.js

@@ -671,8 +671,11 @@ editor = {
         editor.map.setMaxBounds(bounds);
     },
     _last_geometry_url: null,
+    _last_geometry_update_cache_key: null,
+    _last_geometry_cache: {},
     load_geometries: function (geometry_url, highlight_type, editing_id) {
         // load geometries from url
+        var same_url = (editor._last_geometry_url == geometry_url);
         editor._last_geometry_url = geometry_url;
         editor._loading_geometry = true;
         editor._highlight_type = highlight_type;
@@ -688,15 +691,34 @@ editor = {
         editor._graph_edges_to = {};
 
         editor._set_max_bounds();
-        $.getJSON(geometry_url, function(geometries) {
+
+        if (same_url && editor._last_geometry_update_cache_key) {
+            geometry_url += '&update_cache_key='+editor._last_geometry_update_cache_key;
+        }
+        $.getJSON(geometry_url, function(result) {
+            var geometries = [], feature, new_cache = {}, feature_type, feature_id;
+            // geometries cache logic
+            for (var i=0;i<result.geometries.length;i++) {
+                feature = result.geometries[i];
+                if (Array.isArray(feature)) {
+                    // load from cache
+                    feature = editor._last_geometry_cache[feature[0]][feature[1]];
+                }
+                if (!new_cache[feature.properties.type]) {
+                    new_cache[feature.properties.type] = {};
+                }
+                new_cache[feature.properties.type][feature.properties.id] = feature;
+                geometries.push(feature);
+            }
+            editor._last_geometry_cache = new_cache;
+            editor._last_geometry_update_cache_key = result.update_cache_key;
+
             editor.map.removeLayer(editor._highlight_layer);
             editor._highlight_layer.clearLayers();
             if (editor._geometries_layer !== null) {
                 editor.map.removeLayer(editor._geometries_layer);
             }
-            var feature = null,
-                remove_feature = null,
-                i;
+            var remove_feature = null;
             if (editor._editing_id !== null) {
                 for (i=0;i<geometries.length;i++) {
                     feature = geometries[i];

src/c3nav/editor/wrappers.py

@@ -191,8 +191,11 @@ class ModelInstanceWrapper(BaseWrapper):
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
+        self._affected_by_changeset = False
         if self._obj.pk is not None:
-            self._changeset.get_changed_object(self._obj).apply_to_instance(self)
+            changed_object = self._changeset.get_changed_object(self._obj)
+            self._affected_by_changeset = changed_object.pk is not None
+            changed_object.apply_to_instance(self)
 
     def __eq__(self, other):
         if isinstance(other, BaseWrapper):

src/c3nav/mapdata/api.py

@@ -69,7 +69,8 @@ def api_stats(view_name):
     return wrapper
 
 
-def api_etag(permissions=True, etag_func=AccessPermission.etag_func, cache_parameters=None, base_mapdata_check=False):
+def api_etag(permissions=True, etag_func=AccessPermission.etag_func,
+             cache_parameters=None, cache_kwargs=None, base_mapdata_check=False):
     def wrapper(func):
         @wraps(func)
         def wrapped_func(self, request, *args, **kwargs):
@@ -88,6 +89,12 @@ def api_etag(permissions=True, etag_func=AccessPermission.etag_func, cache_param
                     for param, type_ in cache_parameters.items():
                         value = int(param in request.GET) if type_ == bool else type_(request.GET.get(param))
                         cache_key += ':'+urlsafe_base64_encode(str(value).encode())
+                if cache_kwargs is not None:
+                    for name, type_ in cache_kwargs.items():
+                        value = type_(kwargs[name])
+                        if type_ == bool:
+                            value = int(value)
+                        cache_key += ':'+urlsafe_base64_encode(str(value).encode())
                 data = request_cache.get(cache_key)
                 if data is not None:
                     response = Response(data)

src/c3nav/mapdata/models/geometry/base.py

@@ -52,6 +52,9 @@ class GeometryMixin(SerializableMixin):
             result['bounds'] = True
         return result
 
+    def get_geojson_key(self):
+        return (self.__class__.__name__.lower(), self.id)
+
     def to_geojson(self, instance=None) -> dict:
         result = {
             'type': 'Feature',

src/c3nav/mapdata/models/graph.py

@@ -89,3 +89,6 @@ class GraphEdge(AccessRestrictionMixin, models.Model):
         if self.waytype_id is not None:
             result['properties']['color'] = self.waytype.color
         return result
+
+    def get_geojson_key(self):
+        return (self.__class__.__name__.lower(), self.pk)