In TypeScript, I have created a QueryFactory class with two generic type parameters: TQuery and TResponse. My goal is to ensure type safety so that if the TResponse type does not match the expected response type of the TQuery type, the compiler will throw an error.
Below is a snippet of my code:
// Object examples
class Person {
name: string;
age: number;
gender: string;
}
class Book {
name: string;
author: string;
}
// Classes
interface IBaseRequest {}
class RequestBase<T> implements IRequest<T>, IBaseRequest { }
interface IRequest<TResponse> extends IBaseRequest { }
class GetPersonByIdQuery extends RequestBase<Person> implements IRequest<Person>, IBaseRequest { }
class QueryFactory<TQuery, TResponse> { }
// Implementation
new QueryFactory<GetPersonByIdQuery, Person>(); // This is allowed as expected.
new QueryFactory<GetPersonByIdQuery, Book>(); // This should trigger a compilation error
new QueryFactory<GetPersonByIdQuery, string>(); // This should also result in a compilation error
I am looking for a way to enforce that the TResponse type provided to QueryFactory matches the expected response type of the TQuery type. Specifically, the GetPersonByIdQuery class should only permit Person as the response type.
Is there a method to implement this type safety check in TypeScript? How can I modify the QueryFactory class to achieve this?