feat: support bulk actions (#63)

.vscode/extensions/autoDocstring/docstring.mustache

@@ -0,0 +1,35 @@
+{{! Based off of: https://github.com/NilsJPWerner/autoDocstring/blob/master/src/docstring/templates/google-notypes.mustache }}
+{{summaryPlaceholder}}
+
+{{extendedSummaryPlaceholder}}
+{{#parametersExist}}
+
+Args:
+{{#args}}
+    {{var}}: {{descriptionPlaceholder}}
+{{/args}}
+{{#kwargs}}
+    {{var}}: {{descriptionPlaceholder}}
+{{/kwargs}}
+{{/parametersExist}}
+{{#exceptionsExist}}
+
+Raises:
+{{#exceptions}}
+    {{type}}: {{descriptionPlaceholder}}
+{{/exceptions}}
+{{/exceptionsExist}}
+{{#returnsExist}}
+
+Returns:
+{{#returns}}
+    {{descriptionPlaceholder}}
+{{/returns}}
+{{/returnsExist}}
+{{#yieldsExist}}
+
+Yields:
+{{#yields}}
+    {{descriptionPlaceholder}}
+{{/yields}}
+{{/yieldsExist}}

codeforlife/serializers/__init__.py

@@ -3,4 +3,4 @@
 Created on 20/01/2024 at 11:19:12(+00:00).
 """
 
-from .base import *
+from .model import *

codeforlife/serializers/model.py

@@ -0,0 +1,124 @@
+"""
+© Ocado Group
+Created on 20/01/2024 at 11:19:24(+00:00).
+
+Base model serializers.
+"""
+
+import typing as t
+
+from django.db.models import Model
+from rest_framework.serializers import ListSerializer as _ListSerializer
+from rest_framework.serializers import ModelSerializer as _ModelSerializer
+from rest_framework.serializers import ValidationError as _ValidationError
+
+AnyModel = t.TypeVar("AnyModel", bound=Model)
+
+
+class ModelSerializer(_ModelSerializer[AnyModel], t.Generic[AnyModel]):
+    """Base model serializer for all model serializers."""
+
+    # pylint: disable-next=useless-parent-delegation
+    def update(self, instance, validated_data: t.Dict[str, t.Any]):
+        return super().update(instance, validated_data)
+
+    # pylint: disable-next=useless-parent-delegation
+    def create(self, validated_data: t.Dict[str, t.Any]):
+        return super().create(validated_data)
+
+
+class ModelListSerializer(
+    t.Generic[AnyModel],
+    _ListSerializer[t.List[AnyModel]],
+):
+    """Base model list serializer for all model list serializers.
+
+    Inherit this class if you wish to custom handle bulk create and/or update.
+
+    class UserListSerializer(ModelListSerializer[User]):
+        def create(self, validated_data):
+            ...
+
+        def update(self, instance, validated_data):
+            ...
+
+    class UserSerializer(ModelSerializer[User]):
+        class Meta:
+            model = User
+            list_serializer_class = UserListSerializer
+    """
+
+    batch_size: t.Optional[int] = None
+
+    @classmethod
+    def get_model_class(cls) -> t.Type[AnyModel]:
+        """Get the model view set's class.
+
+        Returns:
+            The model view set's class.
+        """
+
+        # pylint: disable-next=no-member
+        return t.get_args(cls.__orig_bases__[0])[  # type: ignore[attr-defined]
+            0
+        ]
+
+    def create(self, validated_data: t.List[t.Dict[str, t.Any]]):
+        """Bulk create many instances of a model.
+
+        https://www.django-rest-framework.org/api-guide/serializers/#customizing-multiple-create
+
+        Args:
+            validated_data: The data used to create the models.
+
+        Returns:
+            The models.
+        """
+
+        model_class = self.get_model_class()
+        return model_class.objects.bulk_create(  # type: ignore[attr-defined]
+            objs=[model_class(**data) for data in validated_data],
+            batch_size=self.batch_size,
+        )
+
+    def update(self, instance, validated_data: t.List[t.Dict[str, t.Any]]):
+        """Bulk update many instances of a model.
+
+        https://www.django-rest-framework.org/api-guide/serializers/#customizing-multiple-update
+
+        Args:
+            instance: The models to update.
+            validated_data: The field-value pairs to update for each model.
+
+        Returns:
+            The models.
+        """
+
+        # Models and data must have equal length and be ordered the same!
+        for model, data in zip(instance, validated_data):
+            for field, value in data.items():
+                setattr(model, field, value)
+
+        model_class = self.get_model_class()
+        model_class.objects.bulk_update(  # type: ignore[attr-defined]
+            objs=instance,
+            fields={field for data in validated_data for field in data.keys()},
+            batch_size=self.batch_size,
+        )
+
+        return instance
+
+    def validate(self, attrs: t.List[t.Dict[str, t.Any]]):
+        # If performing a bulk create.
+        if self.instance is None:
+            if len(attrs) == 0:
+                raise _ValidationError("Nothing to create.")
+
+        # Else, performing a bulk update.
+        else:
+            if len(attrs) == 0:
+                raise _ValidationError("Nothing to update.")
+            if len(attrs) != len(self.instance):
+                raise _ValidationError("Some models do not exist.")
+
+        return attrs