GraphQL Mutation how to make fields optional to update fields only by selection and generate schema

[Kalanamith]

I have a graphql mutation defined as follows

    updateParts(
      partId: String!
      parts: PartRequest!
    ): UpdatePartsResponse!

  input PartRequest {
    name: String!
    image: Strings!
    boltTypes: [Bolts]!
  }


  input Bolts {
    code: String!
    metadata: String!
  }

and the requirement was to update fields upon selection like

• update all

mutation {
  updateParts(
    partId: "0x1223"
    parts: {
      name: "some"
      image: "dark.png"
      boltTypes: [
        { code: "A", metadata: "B" }
       
      ]
    }
  ) 
  }
}

• Update by selection name only

mutation {
  updateParts(
    partId: "0x1223"
    parts: {
      name: "some"
     
    }
  ) 
  }
}

Update by selection , parts only

mutation {
  updateParts(
    partId: "0x1223"
    parts: {
       
      boltTypes: [
        { code: "A", metadata: "B" }
       
      ]
    }
  ) 
  }
}

How to construct a schema to achieve this ?

[benjie]

Make the fields on PartRequest nullable, this makes them optional. Optionality and nullability are effectively equivalent in GraphQL inputs currently (with the exception of where default values are present).