Correct and validate JSON dates when they are read from file

core/models/survex.py

@@ -239,7 +239,20 @@ class Wallet(models.Model):
         if not self.get_json():
             return None
         jsondata = self.get_json()
-        return jsondata["date"]
+
+        datestr = jsondata["date"]
+        if not datestr:
+            return None
+        else:
+            datestr = datestr.replace('.','-')    
+            try:
+                samedate = datetime.date.fromisoformat(datestr)
+            except:
+                try:
+                    samedate = datetime.date.fromisoformat(datestr[:10])
+                except:
+                    samedate = None
+            return samedate.isoformat()
         
     def people(self):
         if not self.get_json():