graphql - GraphQL 和石墨烯

Question

我有一个具有一对多关系的数据库模式。例如，一个部门有很多客户。是否有可能有一个突变来创建一个客户和一个部门并将它们关联起来？或者正确的方法是创建一个客户而不是一个部门，然后相互关联？

在第二种方法中，我需要进行三次而不是一次。有人可以为我提供处理这种情况的 GraphQL 吗？

Answer 1

您可以定义您的突变输入以支持嵌套类型。这将允许您同时发送Department和发送Customer单个突变。

在返回负载中，您可以在查询中指定返回新创建Department的及其关联的Customer.

class Customer(graphene.ObjectType):
    customer_id = graphene.Int(required=True)
    name = graphene.String(required=True)


class Department(graphene.ObjectType):
    department_id = graphene.Int(required=True)
    name = graphene.String(required=True)
    customers = graphene.List(Customer)


class CustomerInput(graphene.InputObjectType):
    name = graphene.String(required=True)


class DepartmentMutation(graphene.relay.ClientIDMutation):

    class Input:
        name = graphene.String(required=True)
        customer = graphene.Field(CustomerInput)

    department = graphene.Field(Department)

    @classmethod
    def mutate_and_get_payload(cls, input, context, info):
        new_department_name = input.get('name')
        new_customer = input.get('customer')
        logger.debug(new_department_name)
        logger.debug(new_customer)
        # validate and persist...
        # we return dummy objects for brevity
        customer = Customer(
            customer_id=1,
            name=new_customer.get('name')
        )
        department = Department(
            department_id=1,
            name=new_department_name,
            customers=[customer]
        )
        return cls(department=department)

您将允许您在一次旅行中变异和查询关联实体。

如果你用Connections它来定义关系，事情会变得有点复杂，但基本原理是一样的。