thoth_json_net_demo.fsx

#r "nuget: Thoth.Json.Net, 7.1.0"

open Thoth.Json.Net

type Foo =
    { Name: string
      Age: int }

module Encoders =
    let fooDecoder : Decoder<Foo> =
        Decode.object (fun fields -> {
            Name = fields.Required.At [ "n" ] Decode.string
            Age = fields.Required.At [ "a" ] Decode.int
        })

    let fooEncoder (foo: Foo) =
        Encode.object 
            [ ("n", Encode.string foo.Name)
              ("a", Encode.int foo.Age)
            ]

type Bar = 
    { Name: string
      FooThingie: Foo }

    static member Decoder : Decoder<Bar> =
        Decode.object (fun fields -> {
            Name = fields.Required.At [ "n" ] Decode.string
            FooThingie = fields.Required.At [ "f" ] Encoders.fooDecoder
        })

    static member Encoder (bar: Bar) =
        Encode.object 
            [ ("n", Encode.string bar.Name)
              ("f", Encoders.fooEncoder bar.FooThingie) ]

let enrich x =
    x
    |> Extra.withCustom Encoders.fooEncoder Encoders.fooDecoder
    |> Extra.withCustom Bar.Encoder Bar.Decoder

[<EntryPoint>]
let main argv =

    let myExtraCoders =
        Extra.empty
        |> enrich

    let f = { Name = "bar"; FooThingie = { Name = "Christian"; Age = 49 } }
    let json = Encode.Auto.toString (1, f, extra = myExtraCoders)
    let f2 = Decode.Auto.fromString<Bar>(json, extra = myExtraCoders)
    
    printfn "%s" json
    printfn "%A" f2
    1