lozlow / bs-atdgen-codec-runtime

bs-atdgen-codec-runtime

bs-atdgen-codec-runtime is a bucklescript runtime for atdgen. It is based on the json type provided by bucklescript and combinators of @glennsl/bs-json.

Installation

yarn add @ahrefs/bs-atdgen-codec-runtime

This package doesn't take care of running atdgen to derive code from type definitions. This step requires the atdgen binary which can be obtained using opam or esy.

Alternatively, if your project is using BuckleScript exclusively (i.e. not using native OCaml or Reason in the backend), you might consider using bs-atdgen-generator in combination with this runtime library, in order to generate the .ml and .mli files from .atd sources without having to use native package managers like esy or opam.

Usage

Add @ahrefs/bs-atdgen-codec-runtime to the bs-dependencies of bsconfig.json.

To write atd type definitions, please have a look at the great atd documentation.

Simple example

Reason code to query and deserialize the response of a REST API. It requires bs-fetch.

let get = (url, decode) =>
  Js.Promise.(
    Fetch.fetchWithInit(
      url,
      Fetch.RequestInit.make(~method_=Get, ()),
    )
    |> then_(Fetch.Response.json)
    |> then_(json => json |> decode |> resolve)
  );

let v: Meetup_t.events =
  get(
    "http://localhost:8000/events",
    Atdgen_codec_runtime.Decode.decode(Meetup_bs.read_events),
  );

Full example

The example directory contains a full example of a simple cli to read and write data in a JSON file.

For a complete introduction from atdgen installation to json manipulation, please refer to Getting started with atdgen and bucklescript.