Further fixes

* fixes race condition on geometry conflict calculation if performed in background process
* simplifies access to smaller buffered geometry
* adds mapping of "qm"->"m2" for UnitChoice in API usage for backwards compatibility

konova/models/geometry.py

@@ -8,13 +8,11 @@ Created on: 15.11.21
 import json
 
 from django.contrib.gis.db.models import MultiPolygonField
-from django.contrib.gis.geos import Polygon
 from django.db import models, transaction
 from django.utils import timezone
 
 from konova.models import BaseResource, UuidModel
 from konova.sub_settings.lanis_settings import DEFAULT_SRID_RLP
-from konova.tasks import celery_check_for_geometry_conflicts
 from konova.utils.wfs.spatial import ParcelWFSFetcher
 
 
@@ -29,7 +27,18 @@ class Geometry(BaseResource):
 
     def save(self, *args, **kwargs):
         super().save(*args, **kwargs)
-        celery_check_for_geometry_conflicts.delay(self.id)
+
+    @property
+    def geom_small_buffered(self):
+        """
+        Returns a smaller buffered version of the geometry.
+        Can be used to shrink the geometry used for intersection purposes to avoid intersection detection on
+        neighbouring geometries.
+
+        Returns:
+
+        """
+        return self.geom.buffer(-0.001)
 
     def check_for_conflicts(self):
         """ Checks for new geometry overlaps
@@ -44,9 +53,8 @@ class Geometry(BaseResource):
             return None
 
         self.recheck_existing_conflicts()
-
         overlapping_geoms = Geometry.objects.filter(
-            geom__intersects=self.geom,
+            geom__intersects=self.geom_small_buffered,
         ).exclude(
             id=self.id
         ).distinct()
@@ -68,14 +76,14 @@ class Geometry(BaseResource):
         """
         all_conflicts_as_conflicting = self.conflicts_geometries.all()
         still_conflicting_conflicts = all_conflicts_as_conflicting.filter(
-            affected_geometry__geom__intersects=self.geom
+            affected_geometry__geom__intersects=self.geom_small_buffered
         )
         resolved_conflicts = all_conflicts_as_conflicting.exclude(id__in=still_conflicting_conflicts)
         resolved_conflicts.delete()
 
         all_conflicted_by_conflicts = self.conflicted_by_geometries.all()
         still_conflicting_conflicts = all_conflicted_by_conflicts.filter(
-            conflicting_geometry__geom__intersects=self.geom
+            conflicting_geometry__geom__intersects=self.geom_small_buffered
         )
         resolved_conflicts = all_conflicted_by_conflicts.exclude(id__in=still_conflicting_conflicts)
         resolved_conflicts.delete()