Specta Serde

Serde support for Specta.

This applies Serde macro attributes on your types to the Specta generated types.

Using with Specta TypeScript

specta-serde exposes two format implementations for usage with any of the exporter crates, like specta-typescript:

• specta_serde::format: unified shape for both serialize and deserialize.
• specta_serde::format_phases: split serialize/deserialize shapes.

format (unified shape)

Use format when serde behavior is symmetric and only a single TypeScript type is produced.

Note: This will error with certain Serde attributes like #[serde(rename(serialize = "a", deserialize = "b"))] as it's unclear what is correct.

use specta::Types;
use specta_typescript::Typescript;

#[derive(specta::Type, serde::Serialize, serde::Deserialize)]
#[serde(rename_all = "camelCase")]
struct User {
    user_id: u32,
}

let types = Types::default().register::<User>();

let output = Typescript::default()
    .export(&types, specta_serde::format)
    .unwrap();

assert!(output.contains("export type User"));
assert!(output.contains("userId: number"));

You should always prefer format_phases where possible as it will generate a more accurate type.

format_phases (split by direction)

Use format_phases when the wire format can differ between serialization and deserialization. This may produce two different types, TypeName_Serialize and TypeName_Deserialize, to accurately represent both phases. It will produce TypeName as TypeName_Serialize | TypeName_Deserialize so the type can be used in a general format when needed.

This is common with directional serde metadata (serialize_with, deserialize_with, from, into, try_from) or explicit #[specta(type = specta_serde::Phased<SerializeTy, DeserializeTy>)] overrides.

use serde::{Deserialize, Serialize};
use serde_with::{OneOrMany, serde_as};
use specta::{Type, Types};
use specta_typescript::Typescript;

#[derive(Type, Serialize, Deserialize)]
#[serde(untagged)]
enum OneOrManyString {
    One(String),
    Many(Vec<String>),
}

#[serde_as]
#[derive(Type, Serialize, Deserialize)]
struct Filters {
    #[serde_as(as = "OneOrMany<_>")]
    #[specta(type = specta_serde::Phased<Vec<String>, OneOrManyString>)]
    tags: Vec<String>,
}

let types = Types::default().register::<Filters>();

let output = Typescript::default()
    .export(&types, specta_serde::format_phases)
    .unwrap();

assert!(output.contains("Filters_Serialize"));
assert!(output.contains("Filters_Deserialize"));
assert!(output.contains("OneOrManyString"));