Dynamic response types for rtkq endpoints

[sbruinsje]

Is it possible to have dynamic response types for an endpoint? Our endpoints support a field parameter that allows you to specify which fields you want to retrieve (retrieving a subset of the fields can be needed for performance reasons).

getContact: build.query<Contact, { field: string[] }>(queryArgs);

When we use the getContact endpoint I want to be able to specify that the return type is Pick<Contact, "id", "name"> when we are requesting the "id" and "name" field.

[EskiMojo14]

no, this isn't possible to support with Typescript.

[sbruinsje]

Just to clarify I didn't mean whether its possible to dynamically determine the return type based on the fields that I specify in the queryArgs, what I meant is whether its possible to achieve something like this:

useGetContactQuery<Pick<Contact, "id" | "name">>({ field: ["id", "name"] });

If not, is there any other option than to always just use Partial<Contact> as return type?

[EskiMojo14]

you could do a type assertion in selectFromResult, i suppose:

useGetContactQuery({ field: ["id", "name"] }, {
  selectFromResult: ({ data, ...rest }) => ({
    ...rest,
    data: data as Pick<Contact, "id" | "name">
  })
});