Custom type mapping

[thebluefish]

I would like to support rust_decimal's Decimal type. Depending on configuration, this type can be represented in serde as either a float or a string. This is further complicated by options covering the whole crate or just specific fields. While generating TypeScript types via tsync, I would like to somehow specify which representation to use.

Currently I can create a separate module exclusively for inclusion in tsync and export custom type mappings there, however I would prefer to erase the type entirely.

Alternatively, I can fork the project and and add the additional type to convert_type directly as a global type mapping. This produces results closer to what I want, but requires more work to maintain.

Neither of these solutions would help the per-field case.

I am wondering about adding a field parameter to override types in-line, something like:

#[derive(Debug, Serialize, Deserialize)]
#[tsync]
pub struct Foo {
    name: Option<String>,
    #[tsync(type = "number")]
    quantity: Decimal,
}

[Wulf]

Yeah, we definitely need something like this. You've probably noticed the hard-coded types for something like chrono's NaiveDate/Time types... it isn't an ideal solution, but it was a hack that got us this far 😅 .

I would love to see something like added to tsync. I really appreciate your detailed explanation of the problem and approaches you've thought of.