Accessing a field with arguments in cache.readFragment

[vitosamson]

I'm trying to do something like the following inside an optimistic update:

modifyCapabilities({ userId, groupId }, cache) {
  const user = cache.readFragment(
    gql`
      fragment _ on UserQuery {
        id
        capabilities(byGroup: $groupId)
      }
    `,
    { id: userId, groupId, __typename: 'UserQuery' }
  )

  return {
    // ... modified user object
  }
}

where capabilities is just a [String!]! type.

Whenever I include the capabilities field in the fragment, readFragment returns null. If I remove that field, the readFragment successfully returns that user. The field definitely exists in the cache, according to the urql dev tools.

Is it not possible to query a field with variables like that in readFragment?

[JoviDeCroock]

Have you tried passing the variable to the thirth argument, the second is meant to be a describing entity and the thirth one is used to signal variables https://github.com/FormidableLabs/urql/blob/main/exchanges/graphcache/src/store/store.ts#L191

[vitosamson]

That did it, thanks!

[vitosamson]

Where do the docs live? I'd like to open a PR to include that information.

[JoviDeCroock]

In here: https://github.com/FormidableLabs/urql/tree/main/docs/graphcache