As using proxy type

[carlocorradini]

Description of the feature

I would like to include a feature similar to serde_with::FromInto:

Serialize value by converting to/from a proxy type with serde support.

This adapter serializes a type O by converting it into a second type T and serializing T. Deserializing works analogue, by deserializing a > T and then converting into O.

struct S {
    #[serde_as(as = "FromInto<T>")]
    #[graphql(as = "T")]
    value: O,
}

The latter eliminates the requirement for wrapper types and/or additional logic because it uses something that GraphQL already understands (i.e. u8, u16, String, ...).

Additionally, it can be used in conjunction with skip_input to eliminate it from an InputObject.

Code example

#[serde_as]
#[derive(Serialize, Deserialize, SimpleObject, InputObject, Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub struct MyObject {
    #[serde_as(as = "FromInto<u8>")]
    #[graphql(as = "u8")]
    pub type: external::enum::Type, // Assume u8 via impl From<u8> and impl From<external::enum::Type>
    #[serde_as(as = "FromInto<u16>")]
    #[serde_as(skip_input, as = "u16")]
    pub only_object: external::Obj, // Assume u16 (only Object) via impl From<external::Obj> for u16
    pub name: String,
}

• type is external::enum::Type, however it is seen as an u8 in both SimpleObject and InputObject thanks to impl From<u8> for external::enum::Type and impl From<external::enum::Type> for u8
• only_object is external::Obj, however it is seen as an u16 in SimpleObject thanks to impl From<external::enum::Type> for u16
• only_object is skipped in InputObject thanks to skip_input

query {
  myObj {
    type, # 100
    onlyObject, # 65535
    name # "Hello World!"
  }
}