Finding FIELD directives on a SelectedField

[ee-usgs]

I've created a @tabular(name: String!) on FIELD directive. It's only defined in my schema - there are no associated classes. The purpose of the directive is to provide the column name for a field if it is later exported as tabular data (CSV, TSV, etc.).

For a query like this:

{
  resultConnection(first: 100) {
    pageInfo {
      hasNextPage, endCursor, tabularMappings { path, name }
    }
    nodes {
      FIRST_FIELD,
      SOME_FIELD_I_DONT_LIKE_THE_NAME_OF @tabular(name: "A_BETTER_NAME")
    }
  }
}

I have one DataFetcher that is wired to provide the entire response. The intention is that it fills in the tabularMappings section with the paths and names to use for exporting the values to tabular formats, e.g. like this:

        "tabularMappings": [
          {
            "path": "FIRST_FIELD",
            "name": "firstField" // pretty column name
          }, {
            "path": "SOME_FIELD_I_DONT_LIKE_THE_NAME_OF",
            "name": "A_BETTER_NAME" // The user is specifically requesting this name
          }
        ]

The problem is, cannot find the directive anywhere within the SelectedField or anywhere else in the DataFetchingEnvironment. Where can I find it?

Any suggestions appreciated,

--Eric Everman

[bbakerman]

graphql.schema.DataFetchingEnvironment#getQueryDirectives will give you access to the query directives on a field

SOME_FIELD_I_DONT_LIKE_THE_NAME_OF @tabular(name: "A_BETTER_NAME")

I am not sure this will work the way you think it will. The engine REALLY wants to return data results using the field names as they are defined in the schema

A client can use a field alias to rename field names in results

nodes {
      FIRST_FIELD,
     A_BETTER_NAME :  SOME_FIELD_I_DONT_LIKE_THE_NAME_OF
    }

https://graphql.org/learn/queries/#aliases

[eeverman]

I will try graphql.schema.DataFetchingEnvironment#getQueryDirectives.

Just to be clear, the intention is not to create an alias: It is to create some extra metadata, returned in the pageInfo section, that can be used by a downstream system to export the data into a tabular format. In some cases the tabular export name is not a valid GraphQL field name.