JSON deserialization from payload fails with i128 is not supported

[pocesar]

MetadatumRendition enum got a i128, but fails because of a serde bug when using #[serde(flatten)]. enabling arbitrary_precision flag doesn't help

see serde-rs/serde#1183
serde-rs/json#625

simple repro:

    let data = json!(oura::model::MetadataRecord {
      label: "hello".to_string(),
      content: oura::model::MetadatumRendition::IntScalar(2_i128.pow(90)),
    });

    let json_value: oura::model::MetadataRecord = serde_json::from_value(data).unwrap(); // unwrap fails here, Error("i128 is not supported", line: 0, column: 0)
    let parsed = serde_json::to_string(&json_value).unwrap();

    let data = serde_json::from_str::<oura::model::MetadataRecord>(&parsed).unwrap();
    println!("{:?}", parsed);
    println!("{:?}", data);

this change works:

#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq)]
pub struct MetadataRecord {
    pub label: String,
    // no #[serde(flatten)]
    pub content: MetadatumRendition,
}

a couple of solutions:

• remove the flatten. makes the nested struct messy
• serialize/deserialize to BigInt instead, including anything that is higher than Number.MAX_SAFE_INTEGER from JS
• create a custom se/deserializer to output as those >= Number.MAX_SAFE_INTEGER as string

regarding the interop in JSON types from the RFC https://datatracker.ietf.org/doc/html/rfc7159#page-7:

Note that when such software is used, numbers that are integers and
are in the range [-(2^53)+1, (2^53)-1] are interoperable in the
sense that implementations will agree exactly on their numeric
values