package melange-transit

melange-transit

Transit JSON reader and writer bindings for Melange.

This library wraps the cognitect/transit-js JSON reader and writer while exposing OCaml values through the existing Transit.Json API. MessagePack is intentionally out of scope because transit-js does not support MessagePack encoding.

The Transit.Json.value constructors mirror the transit-js runtime kinds that can be represented consistently: Binary maps to transit-js binary values, and Date maps to JavaScript Date values stored as milliseconds since the Unix epoch. Transit char and quote ground values are exposed as their underlying values because the transit-js reader unwraps them.

Usage

let payload =
  Transit.Json.Map
    [
      (Transit.Json.Keyword "name", Transit.Json.String "Ada");
      (Transit.Json.Keyword "roles", Transit.Json.Array [ Transit.Json.String "admin" ]);
    ]

let json = Transit.Json.to_string payload
let decoded = Transit.Json.of_string json

Normal JSON mode uses transit.writer("json"). Verbose mode uses transit.writer("json-verbose"):

let json = Transit.Json.to_string ~mode:Transit.Json.Verbose payload

transit-js runtime semantics are preserved. For example, top-level scalar values are quote-wrapped by the writer, duplicate map keys follow JavaScript Map semantics, and json-verbose date values are written as ISO timestamps.

Development

dune runtest