A Pydantic integration for Graphene.
pip install "graphene-pydantic"Here is a simple Pydantic model:
import pydantic class PersonModel(pydantic.BaseModel): id: uuid.UUID first_name: str last_name: strTo create a GraphQL schema for it you simply have to write the following:
import graphene from graphene_pydantic import PydanticObjectType class Person(PydanticObjectType): class Meta: model = PersonModel # only return specified fields only_fields = ("name",) # exclude specified fields exclude_fields = ("id",) class Query(graphene.ObjectType): people = graphene.List(Person) def resolve_people(self, info): return get_people() # function returning `PersonModel`s schema = graphene.Schema(query=Query)Then you can simply query the schema:
query = ''' query { people { firstName, lastName } } ''' result = schema.execute(query)graphene_pydantic supports forward declarations and circular references, but you will need to call the resolve_placeholders() method to ensure the types are fully updated before you execute a GraphQL query. For instance:
class NodeModel(BaseModel): id: int name: str labels: 'LabelsModel' class LabelsModel(BaseModel): node: NodeModel labels: typing.List[str] class Node(PydanticObjectType): class Meta: model = NodeModel class Labels(PydanticObjectType): class Meta: model = LabelsModel Node.resolve_placeholders() # make the `labels` field work Labels.resolve_placeholders() # make the `node` field workPlease see the examples directory for more.
This project is under the Apache License.
This project depends on third-party code which is subject to the licenses set forth in Third Party Licenses.
Please see the Contributing Guide. Note that you must sign the CLA.
Note that even though Pydantic is perfectly happy with fields that hold mappings (e.g. dictionaries), because GraphQL's type system doesn't have them those fields can't be exported to Graphene types. For instance, this will fail with an error Don't know how to handle mappings in Graphene:
import typing from graphene_pydantic import PydanticObjectType class Pet: pass class Person: name: str pets_by_name: typing.Dict[str, Pet] class GraphQLPerson(PydanticObjectType): class Meta: model = PersonHowever, note that if you use exclude_fields or only_fields to exclude those values, there won't be a problem:
class GraphQLPerson(PydanticObjectType): class Meta: model = Person exclude_fields = ("pets_by_name",)
