feat: Enforce validation for updating nested relations (#405)

* Perform full_clean for updating nested relations

* Add tests for validation on nested updates

* Perform full clean only if obj is not None

* Pass full_clean options to updatem2m as well

strawberry_django/mutations/resolvers.py

@@ -349,7 +349,7 @@ def update(
         instance.save()
 
         for field, value in m2m:
-            update_m2m(info, instance, field, value)
+            update_m2m(info, instance, field, value, full_clean)
 
         retval.append(instance.__class__._default_manager.get(pk=instance.pk))
 
@@ -422,6 +422,7 @@ def update_m2m(
     instance: Model,
     field: ManyToManyField | ForeignObjectRel,
     value: Any,
+    full_clean: bool | FullCleanOptions = True,
 ):
     if value is UNSET:
         return
@@ -457,6 +458,8 @@ def update_m2m(
     to_delete = []
     need_remove_cache = False
 
+    full_clean_options = full_clean if isinstance(full_clean, dict) else {}
+
     values = value.set if isinstance(value, ParsedObjectList) else value
     if isinstance(values, list):
         if isinstance(value, ParsedObjectList) and getattr(value, "add", None):
@@ -474,6 +477,8 @@ def update_m2m(
                 if data:
                     for k, inner_value in data.items():
                         setattr(obj, k, inner_value)
+                    if full_clean:
+                        obj.full_clean(**full_clean_options)
                     obj.save()
 
                 if hasattr(manager, "through"):
@@ -496,13 +501,17 @@ def update_m2m(
 
                     for k, inner_value in through_defaults.items():
                         setattr(im, k, inner_value)
+                    if full_clean:
+                        im.full_clean(**full_clean_options)
                     im.save()
                 elif obj not in existing:
                     to_add.append(obj)
 
                 existing.discard(obj)
             else:
                 obj, _ = manager.get_or_create(**data)
+                if full_clean:
+                    obj.full_clean(**full_clean_options)
                 existing.discard(obj)
 
         for remaining in existing:
@@ -516,6 +525,8 @@ def update_m2m(
         for v in value.add or []:
             obj, data = _parse_data(info, manager.model, v)
             if obj and data:
+                if full_clean:
+                    obj.full_clean(**full_clean_options)
                 manager.add(obj, **data)
             elif obj:
                 # Do this later in a bulk

tests/models.py

@@ -1,6 +1,6 @@
 from typing import TYPE_CHECKING, Optional
 
-from django.core.exceptions import ImproperlyConfigured
+from django.core.exceptions import ImproperlyConfigured, ValidationError
 from django.db import models
 
 from strawberry_django.descriptors import model_property
@@ -9,6 +9,11 @@
     from django.db.models.manager import RelatedManager
 
 
+def validate_fruit_type(value: str):
+    if "rotten" in value:
+        raise ValidationError("We do not allow rotten fruits.")
+
+
 class Fruit(models.Model):
     name = models.CharField(max_length=20)
     color_id: Optional[int]
@@ -43,7 +48,7 @@ class Color(models.Model):
 
 
 class FruitType(models.Model):
-    name = models.CharField(max_length=20)
+    name = models.CharField(max_length=20, validators=[validate_fruit_type])
 
 
 class User(models.Model):

tests/mutations/test_mutations.py

@@ -57,6 +57,15 @@ def test_update(mutation, fruits):
     ]
 
 
+def test_update_m2m_with_validation_error(mutation, fruit):
+    result = mutation(
+        '{ fruits: updateFruits(data: { types: [{ name: "rotten"} ] }) { id types {'
+        " name } }}",
+    )
+    assert result.errors
+    assert result.errors[0].message == "{'name': ['We do not allow rotten fruits.']}"
+
+
 def test_update_lazy_object(mutation, fruit):
     result = mutation(
         '{ fruit: updateLazyFruit(data: { name: "orange" }) { id name } }',

tests/types.py

@@ -55,7 +55,7 @@ class GeoFieldPartialInput(GeoField):
 
 @strawberry_django.input(models.Fruit)
 class FruitInput(Fruit):
-    pass
+    types: List[FruitTypeInput] | None  # noqa: UP006
 
 
 @strawberry_django.input(models.Color)
@@ -70,7 +70,7 @@ class FruitTypeInput(FruitType):
 
 @strawberry_django.input(models.Fruit, partial=True)
 class FruitPartialInput(FruitInput):
-    pass
+    types: List[FruitTypePartialInput] | None  # noqa: UP006
 
 
 @strawberry_django.input(models.Color, partial=True)