Custom scalar that maps to arbitrary type?

[spencerwilson]

Hello,

I'm wondering if there's a way to use @graphql-codegen/cli's custom scalar support with an arbitrary, non-globally-defined type. E.g.,

config:
  scalars:
    Foo: MyExoticScalar  # not just `any`, or `string`, etc.

But when compiled, tsc rejects the resulting .ts file due to

src/generated/graphql.ts:15:9 - error TS2304: Cannot find name 'MyExoticScalar'.

15   Foo: MyExoticScalar;
          ~~~~~~~~~~~~~~

Alternatively, if I omit the ScalarsMap shown above altogether, the default behavior is akin to if I'd given the following ScalarsMap:

config:
  scalars:
    Foo: any

...which is unappealing for reasons of being weakly typed.

Is there some @graphql-codegen/cli config I'm missing that would "teach" it add some import statements to emitted TypeScript modules so that they contain all the names they need to in order to be valid? Thanks in advance.

[dotansimha]

@spencerwilson sure! we support a format like this:

scalars:
  Upload: 'graphql-upload#FileUpload'

(it's PACKAGE_NAME#IDENTIFIER_NAME)

In more complex use-cases, you can use the identifier name and use add plugin, for example:

config:
  MyGqlType: 'A'
plugins:
  - add:
      content: "import A from 'somewhere'";
  - typescript

[spencerwilson]

This looks great, thanks! I'll follow up if I have trouble getting this working.

[gblikas]

@spencerwilson sure! we support a format like this:

scalars:
  Upload: 'graphql-upload#FileUpload'

(it's PACKAGE_NAME#IDENTIFIER_NAME)

In more complex use-cases, you can use the identifier name and use add plugin, for example:

config:
  MyGqlType: 'A'
plugins:
  - add:
      content: "import A from 'somewhere'";
  - typescript

@dotansimha Why is this not documented anywhere?! If it is, a stronger reference to it should be made clear.

[Urigo]

@gblikas could you help us send a pull request to the docs to add it in the right places?