Transforming Custom Input Type to Another Type in Middleware

[islamaliev]

I'm working on a GraphQL API where I have a custom input type, let's call it SpecialType. This type is used in various parts of the schema, particularly in mutations. The idea is to collect all these SpecialType inputs, process them through a specialized service, and then convert them to a string ID. This string ID should then be passed to the resolvers.

Here's a simplified schema to illustrate:

input SpecialType {
  field1: String!
  field2: String!
  # ... other fields
}

input SomeInput {
  specialField1: SpecialType!
  specialField2: SpecialType!
  # ... other fields
}

type Mutation {
  handleSomething(input: SomeInput!): Response!
}

I want to handle this transformation in a middleware so that the resolvers are completely unaware of the SpecialType and the specialized service. They should only receive the string ID.

I've tried using HandlerExtension and FieldMiddleware, but it's becoming complex and I'm not sure if it will work as expected.

I presume that I will need to create a custom plugin that alters a bit generation of golang code for the SpecialType.

Questions:

• Is there a recommended way to achieve this transformation in gqlgen middleware?
• How can I access and modify the SpecialType inputs before they reach the resolver?
• Are there any examples or best practices for this kind of operation?

Any guidance would be greatly appreciated.