Missing selection set for object GraphQL+Apollo error

Question

I have a set of mutations that trigger the local state of certain types of popups. They\'re generally set up like this:

  openDialog: (_, variables, { cache }) =         


        

Answer 1

Answer to the actual problem seems lay in the query. Initially Apollo client was not validating types for @client queries/mutations so your mutation could look like you wrote it in the question:

mutation AlertOpenDialog($type: String!) {
  openDialog(type: $type) @client
}

the correct way of writing above is to specify (select) all the simple type (scalar) fields you wanna get in a response. So in regard to the @Vic answer the mutation should look more like:

mutation AlertOpenDialog($type: String!) {
  openDialog(type: $type) @client {
    dialog {
      id
    }
  }
}

Answer 2

Solution is to add fields to the query (vs. declaring the top-level object you want to fetch without specifying the fields to fetch). If you have something like:

{
  popups @client {
    id
    dialog
  }
}

you must declare some fields to fetch inside dialog, for example id:

{
  popups @client {
    id
    dialog {
      id
    }
  }
}

Answer 3

The fix for this turned out to work by treating the dialog field as a string instead of an object. Changing the function to this did the trick and made the errors go away:

  openDialog: (_, variables, { cache }) => {
    const data = {
      popups: {
        ...popups,
        dialog: variables.type
      }
    };

    cache.writeData({
      data: data
    });
    return null;
  }