Key information validation clashes with the semantics of multi subscriptions

[DawidNiezgodka]

I wanted to test multi-subscriptions using CLI. I created a gateway and applied the following schema:

type Query {
    findPurchase(purchaseId: String): Purchase @topic(name: "purchase", keyArgument: "purchaseId")
    allPurchases: [Purchase!] @topic(name: "purchase")
}

type Purchase {
    purchaseId: String!
    productId: Int!
    userId: Int!
    product: Product @topic(name: "product", keyField: "productId")
    amount: Int
    price: Price
}

type Product {
    productId: Int!
    name: String
    description: String
    price: Price
}

type Price {
    total: Float
    currency: String
}

type Click {
    userId: Int!
    timestamp: Int
}

type Subscription {
    userStatistics: UserStatistics
}

type UserStatistics {
    purchase: Purchase @topic(name: "purchase")
    click: Click @topic(name: "click")
}

I received the following error: Internal Server Error: {"type":"errors/serverError","title":"Internal Server Error","code":500,"detail":"An unexpected error occurred:When the return type is not a list for a non-mutation and non-subscription type, key information (keyArgument or keyField) is needed.","uriPath":"/control/schema"} Could not apply schema to gateway: multisubstest

Investigation of the error message led me to the one of the Validation Rules - KeyInformation

The semantics of multi subscription that transfers topic directives from the Subscription type to the user-defined type clashes with this rule.

[DawidNiezgodka]

This has been solved by disabling the validation rule. We will refactor the validation rules so that the one that was disabled can be enabled again. See: #94.