How to make return type of resolvers partial?

[mrctrifork]

Hi I am using this configuration file:

overwrite: true
schema: "src/**/*.(resolver|type).ts"
documents: null
generates:
  src/graphql/generated/graphql.ts:
    plugins:
      - "typescript"
      - "typescript-resolvers"
    config:
      typesSuffix: GQL
      resolverTypeSuffix: Resolver

Works fine but it's really annoying to cast as any as TypeGQL every time I want to delegate a property of the returned object to another resolver.

I've also tried adding the option:

config:
  defaultMapper: Partial<{T}>

But that also modifies the parameters of my resolvers to be Partial<Parent> or something like that.

How do I go about making only the return type of the resolver Partial?

[ayaanqui]

Were you able to find a solution to this, I'm also facing a similar problem and can't find any resources online that explain how this can be achieved.

[mrctrifork]

No I did not find a solution, I just moved on with de-structuring patterns and unsafe casts

[ardatan]

What you return from the resolver is the root argument of the field resolver. I am not sure I understand the usecase. cc @dotansimha

[mrctrifork]

Hi, essentially what the code generator produces is something like

export type SomeResolver<TContext> = {
  sample(parent: Parent, arguments: SampleArguments, context: TContext, info: any): Sample
}

To which, whenever I implement the resolver that provides some of the fields I find myself having to do something like:

return response as any as Sample

On the other hand there's the defaultMapper option:

config:
  defaultMapper: Partial<{T}>

When setting it it generates such thing

export type SomeResolver<TContext> = {
  sample(parent: Partial<Parent>, arguments: SampleArguments, context: TContext, info: any): Partial<Sample> 
}

Which works, the return type is Partial<Sample> but the parent is also Partial<Parent> which is undesired.

So my question is: How can I have the complete Parent as an argument and only mark as partial the return type of my resolver?

[stabai]

I came to this question because I'm new to GraphQL and didn't know of defaultMapper. From reading this, it sounds like all you need is a TypeScript type that you plug into that, and then everything will work.

It seems that a type structure like this would work well:

interface DataObject {
  id: string;
}
type RootDataObject<Type extends DataObject> = {
  [Key in keyof Type]: Type[Key] extends DataObject ? PartialDataObject<Type[Key]> : Type[Key];
};
type PartialDataObject<Type extends DataObject> = Pick<Type, 'id'> & {
  [Key in Exclude<keyof Type, 'id'>]?: Type[Key] extends DataObject ? Partial<Type[Key]> : Type[Key];
};

This allows you to keep the entire root object intact, but any of its properties that are objects with an id field will be stripped down so that only the id field is required and all of the rest are optional. This may not be exactly the behavior you want, but it was the desired behavior in my case.

I'm also not entirely sure I understand the original question and that it's somewhat old now, but I'd be curious to know if anyone finds this helpful.