elm-toulouse/cbor/1.0.0

RFC 7049

The Concise Binary Object Representation (CBOR) is a data format whose design goals include the possibility of extremely small code size, fairly small message size, and extensibility without the need for version negotiation. These design goals make it different from earlier binary serializations such as ASN.1 and MessagePack.

Getting Started

Installation

elm install elm-toulouse/cbor

Usage

import Url exposing (Url)
import Cbor.Decode as D
import Cbor.Encode as E


type alias Album =
    { artist : String
    , title : String
    , year : Int
    , tracks : List ( String, Duration )
    , links : List Url
    }

type Duration
    = Duration Int


-- ENCODER

encodeAlbum : Album -> E.Encoder
encodeAlbum { artist, title, year, tracks, links } =
    let 
        link =  
            Url.toString >> E.string
      
        track = 
            E.pair E.string (\(Duration d) -> E.int d)
    in
    E.sequence 
      [ E.string artist
      , E.string title
      , E.int year
      , E.list track tracks
      , E.list link links
      ]


-- DECODER

decodeAlbum : D.Decoder Album
decodeAlbum =
    let
        link =
            D.string
                |> D.map Url.fromString
                |> D.andThen (Maybe.map D.succeed >> Maybe.withDefault D.fail)

        track =
            D.pair D.string (D.map Duration D.int)
    in
    D.map5 Album
        D.string
        D.string
        D.int
        (D.list track)
        (D.list link)

Testing

Code coverage available here

Changelog

CHANGELOG.md