From 167be0c24e74805ca20278c2ca7597ce7fbce0d0 Mon Sep 17 00:00:00 2001
From: mpeltriaux <Michel.Peltriaux@sgdnord.rlp.de>
Date: Fri, 16 Sep 2022 12:09:25 +0200
Subject: [PATCH] Bugfix Parcel calculation

* fixes a bug where neighbouring parcels would be detected using Intersection operation as well
---
 konova/forms/geometry_form.py                 |  2 +-
 konova/utils/wfs/spatial.py                   | 31 +++++++++----------
 .../map/client/libs/netgis/MapOpenLayers.js   |  2 +-
 3 files changed, 17 insertions(+), 18 deletions(-)

diff --git a/konova/forms/geometry_form.py b/konova/forms/geometry_form.py
index 3c957aa..5d25a85 100644
--- a/konova/forms/geometry_form.py
+++ b/konova/forms/geometry_form.py
@@ -130,4 +130,4 @@ class SimpleGeomForm(BaseForm):
             )
         # Start the parcel update procedure in a background process
         celery_update_parcels.delay(geometry.id)
-        return geometry
\ No newline at end of file
+        return geometry
diff --git a/konova/utils/wfs/spatial.py b/konova/utils/wfs/spatial.py
index e6cae84..5578c35 100644
--- a/konova/utils/wfs/spatial.py
+++ b/konova/utils/wfs/spatial.py
@@ -11,10 +11,11 @@ from json import JSONDecodeError
 from time import sleep
 
 import requests
-from django.contrib.gis.db.models.functions import AsGML, Transform, MakeValid
+from django.contrib.gis.db.models.functions import AsGML, MakeValid
+from django.db.models import Func, F
 from requests.auth import HTTPDigestAuth
 
-from konova.settings import DEFAULT_SRID_RLP, PARCEL_WFS_USER, PARCEL_WFS_PW, PROXIES
+from konova.settings import PARCEL_WFS_USER, PARCEL_WFS_PW, PROXIES
 
 
 class AbstractWFSFetcher:
@@ -72,33 +73,34 @@ class ParcelWFSFetcher(AbstractWFSFetcher):
         self.geometry_property_name = geometry_property_name
 
     def _create_spatial_filter(self,
-                               geometry_operation: str,
-                               filter_srid: str = None):
+                               geometry_operation: str):
         """ Creates a xml spatial filter according to the WFS filter specification
 
+        The geometry needs to be shrinked by a very small factor (-0.01) before a GML can be created for intersection
+        checking. Otherwise perfect parcel outline placement on top of a neighbouring parcel would result in an
+        intersection hit, despite the fact they do not truly intersect just because their vertices match.
+
         Args:
             geometry_operation (str): One of the WFS supported spatial filter operations (according to capabilities)
-            filter_srid (str): Used to transform the geometry into the spatial reference system identified by this srid
 
         Returns:
             spatial_filter (str): The spatial filter element
         """
         from konova.models import Geometry
-        if filter_srid is None:
-            filter_srid = DEFAULT_SRID_RLP
-        geom_gml = Geometry.objects.filter(
+
+        geom = Geometry.objects.filter(
             id=self.geometry_id
         ).annotate(
-            transformed=Transform(srid=filter_srid, expression="geom")
+            smaller=Func(F('geom'), -0.001, function="ST_Buffer")
         ).annotate(
-            gml=AsGML(MakeValid('transformed'))
-        ).first().gml
+            gml=AsGML(MakeValid('smaller'))
+        ).first()
+        geom_gml = geom.gml
         spatial_filter = f"<Filter><{geometry_operation}><PropertyName>{self.geometry_property_name}</PropertyName>{geom_gml}</{geometry_operation}></Filter>"
         return spatial_filter
 
     def _create_post_data(self,
                           geometry_operation: str,
-                          filter_srid: str = None,
                           typenames: str = None,
                           start_index: int = 0,
                           ):
@@ -106,15 +108,13 @@ class ParcelWFSFetcher(AbstractWFSFetcher):
 
         Args:
             geometry_operation (str): One of the WFS supported spatial filter operations (according to capabilities)
-            filter_srid (str): Used to transform the geometry into the spatial reference system identified by this srid
 
         Returns:
             _filter (str): A proper xml WFS filter
         """
         start_index = str(start_index)
         spatial_filter = self._create_spatial_filter(
-            geometry_operation,
-            filter_srid
+            geometry_operation
         )
         _filter = f'<wfs:GetFeature service="WFS" version="{self.version}" xmlns:wfs="http://www.opengis.net/wfs/2.0" xmlns:fes="http://www.opengis.net/fes/2.0" xmlns:myns="http://www.someserver.com/myns" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/wfs/2.0 http://schemas.opengis.net/wfs/2.0.0/wfs.xsd" count="{self.count}" startindex="{start_index}" outputFormat="application/json; subtype=geojson"><wfs:Query typeNames="{typenames}">{spatial_filter}</wfs:Query></wfs:GetFeature>'
         return _filter
@@ -144,7 +144,6 @@ class ParcelWFSFetcher(AbstractWFSFetcher):
         while start_index is not None:
             post_body = self._create_post_data(
                 spatial_operator,
-                filter_srid,
                 typenames,
                 start_index
             )
diff --git a/templates/map/client/libs/netgis/MapOpenLayers.js b/templates/map/client/libs/netgis/MapOpenLayers.js
index 807b057..392b1c7 100644
--- a/templates/map/client/libs/netgis/MapOpenLayers.js
+++ b/templates/map/client/libs/netgis/MapOpenLayers.js
@@ -396,7 +396,7 @@ netgis.MapOpenLayers.prototype.clearAll = function()
 	{
 		if(this.layers[i] === this.editLayer){
 			continue;
-		};
+		}
 		this.map.removeLayer( this.layers[ i ] );
 	}
 	
-- 
2.38.5