Merge pull request #143 from CodeYellowBV/reduced-queries-in-full-clean

Reduced queries in full clean

binder/models.py

@@ -456,7 +456,7 @@ def save(self, *args, **kwargs):
 		return super().save(*args, **kwargs)
 
 
-	def full_clean(self, *args, **kwargs):
+	def full_clean(self, exclude=None, *args, **kwargs):
 		# Determine if the field needs an extra nullability check.
 		# Expects the field object (not the field name)
 		def field_needs_nullability_check(field):
@@ -467,10 +467,19 @@ def field_needs_nullability_check(field):
 			return False
 
 
+		# Gather unchanged fields if LoadedValues mixin available, to
+		# avoid querying uniqueness constraints for unchanged
+		# relations (an useful performance optimization).
+		if hasattr(self, 'field_changed'):
+			exclude = set(exclude) if exclude else set()
+			for f in self.binder_concrete_fields_as_dict(skip_deferred_fields=True):
+				if not self.field_changed(f):
+					exclude.add(f)
+
 		validation_errors = defaultdict(list)
 
 		try:
-			res = super().full_clean(*args, **kwargs)
+			res = super().full_clean(exclude=exclude, *args, **kwargs)
 		except ValidationError as ve:
 			if hasattr(ve, 'error_dict'):
 				for key, value in ve.error_dict.items():

binder/plugins/loaded_values.py

@@ -27,14 +27,14 @@ def field_changed(self, *fields):
             return True
 
         for field in fields:
+            field_def = self._meta.get_field(field)
+
             try:
-                current_value = getattr(self, field)
+                current_value = getattr(self, field_def.attname)
             except ObjectDoesNotExist:
                 current_value = None
 
-            if isinstance(current_value, Model):
-                current_value = current_value.pk
-            elif isinstance(current_value, FieldFile):
+            if isinstance(current_value, FieldFile):
                 current_value = current_value.name
                 if current_value is None:
                     current_value = ''