Trait Codec

Source

pub trait Codec<T: ?Sized> {
    // Required methods
    fn content_type() -> ContentType;
    fn encode(value: &T) -> Result<Vec<u8>, DecodeError>;
}

Expand description

Encoding strategy for a typed body. Four first-party codecs ship here, all self-describing so LaserData Cloud’s projector can index their fields without a schema: Json (serde_json), Msgpack (rmp_serde), Cbor (ciborium), and Bson (bson, native-only feature). For a schema-first format (Avro or Protobuf), Arrow, or your own framing, implement Codec on a marker type. The codec advertises its ContentType so consumers can decode downstream.

The trait is generic on T so codecs can constrain the body type they accept. Serde-based codecs constrain T: Serialize, a Prost codec constrains T: prost::Message.

struct AvroCodec<S>(std::marker::PhantomData<S>);
// Where `S` is your generated Avro schema:
// impl<S: AvroSerialize> Codec<S> for AvroCodec<S> {
//     fn content_type() -> ContentType { ContentType::Avro }
//     fn encode(value: &S) -> Result<Vec<u8>, DecodeError> {
//         avro::to_avro_bytes(value).map_err(|e| DecodeError::Encode(e.to_string()))
//     }
// }