#49 Calculation implementation

* implements update routine for Geometry model
* reorganizes fields of Parcel and District
* adds tests
* simplifies usage of ParcelWFSFetcher

konova/models/parcel.py

@@ -22,28 +22,30 @@ class Parcel(UuidModel):
     To avoid conflicts due to german Umlaute, the field names are shortened and vocals are dropped.
 
     """
-    geometries = models.ManyToManyField("konova.Geometry", related_name="parcels", null=True, blank=True)
+    geometries = models.ManyToManyField("konova.Geometry", related_name="parcels", blank=True)
     district = models.ForeignKey("konova.District", on_delete=models.SET_NULL, null=True, blank=True, related_name="parcels")
     flrstck_nnr = models.CharField(
         max_length=1000,
-        help_text="Flurstücksnenner"
+        help_text="Flurstücksnenner",
+        null=True,
+        blank=True,
     )
     flrstck_zhlr = models.CharField(
         max_length=1000,
-        help_text="Flurstückszähler"
+        help_text="Flurstückszähler",
+        null=True,
+        blank=True,
     )
     flr = models.CharField(
         max_length=1000,
-        help_text="Flur"
-    )
-    gmrkng = models.CharField(
-        max_length=1000,
-        help_text="Gemarkung"
+        help_text="Flur",
+        null=True,
+        blank=True,
     )
     updated_on = models.DateTimeField(auto_now_add=True)
 
     def __str__(self):
-        return f"{self.gmrkng} | {self.flr} | {self.flrstck_nnr} | {self.flrstck_zhlr}"
+        return f"{self.flr} | {self.flrstck_nnr} | {self.flrstck_zhlr}"
 
 
 class District(UuidModel):
@@ -54,18 +56,24 @@ class District(UuidModel):
     District.
 
     """
+    gmrkng = models.CharField(
+        max_length=1000,
+        help_text="Gemarkung",
+        null=True,
+        blank=True,
+    )
     gmnd = models.CharField(
         max_length=1000,
-        help_text="Gemeinde"
-    )
-    vg = models.CharField(
-        max_length=1000,
-        help_text="Verbandsgemeinde",
+        help_text="Gemeinde",
+        null=True,
+        blank=True,
     )
     krs = models.CharField(
         max_length=1000,
-        help_text="Kreis"
+        help_text="Kreis",
+        null=True,
+        blank=True,
     )
 
     def __str__(self):
-        return f"{self.krs} | {self.vg} | {self.gmnd}"
+        return f"{self.gmrkng} | {self.gmnd} | {self.krs}"