在 GraphQL 中不能有带有嵌套字段的输入类型。 错误：预期类型是 GraphQLInputType，但它不是

Question

I have a query where I want to give as input a nested structure of a shopping cart object. I also defined the very same structure as data classes in Kotlin.

This is the schema.graphqls :

type Query {
    calculatePalletDeliveryCosts(input: ShoppingCartInput): Int
}

input ShoppingCartInput {
    products: [ShoppingCartProductInput!]!,
}

input ShoppingCartProductInput {
    productOrderDetails: ProductOrderDetailsInput
}

input ProductOrderDetailsInput {
    orderUnits: [OrderUnitInput]
    quantity: Float!
}

input OrderUnitInput {
    code: String!
}

And this these are the corresponding classes:

data class ShoppingCartInput (
    val products: List<ShoppingCartProductInput>,
)

data class ShoppingCartProductInput(
    val productOrderDetails: ProductOrderDetailsInput
)

data class ProductOrderDetailsInput(
    val orderUnit: OrderUnitInput,
    val quantity: Float
)

data class OrderUnitInput(
    val code: String
)

However starting the application context always yields:

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'graphQLSchema' defined in class path resource [graphql/kickstart/tools/boot/GraphQLJavaToolsAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [graphql.schema.GraphQLSchema]: Factory method 'graphQLSchema' threw exception; nested exception is graphql.kickstart.tools.SchemaError: Expected type 'OrderUnitInput' to be a GraphQLInputType, but it wasn't! Was a type only permitted for object types incorrectly used as an input type, or vice-versa?

Answer 1

I just realized I had inconsistency in my schema.graphqls .

Schema says:

input ProductOrderDetailsInput {
    orderUnits: [OrderUnitInput]
    quantity: Float!
}

But the class was

data class ProductOrderDetailsInput(
    val orderUnit: OrderUnitInput,
    val quantity: Float
)

I matched them both so now it works