Unable to deserialize JsonProvider types

Hi, thank you for your library.

I successfully serialized the type generated by the JsonProvider type provider, but when I try to deserialize I get an exception:

Could not create an instance of type FSharp.Data.Runtime.BaseTypes.IJsonDocument. Type is an interface or abstract class and cannot be instantiated. Path ‘folders[0].JsonValue’, line 1, position 25.

use db = new LiteDatabase("wunderlist.db", FSharpBsonMapper())

type F = JsonProvider<"FoldersJsonSample.json",  RootName = "Folder">
let folders = F.Load(....)
{ folders = folders } |> db.GetCollection<BackUp>().Insert |> ignore

let get = db.GetCollection<BackUp>().FindAll() // <- exception

would you be able to suggest a workaround or fix it?

Thank you.

[UnoSD]

Here it is:

let rec toBsonValue value =
    let toBsonDictionary (record : (string * JsonValue)[]) =
        record |>
        Array.map (fun (name, value) -> 
                        KeyValuePair((if name = "id" then "_id" else name), toBsonValue value)) |>
        (fun x -> new Dictionary<string, BsonValue>(x))

    let toBsonArray (array : JsonValue[]) =
        array |>
        Array.map (fun value -> toBsonValue value)

    let (|Integer|Decimal|) input =
        match System.Int64.TryParse (input.ToString()) with
        | true, value -> Integer value
        | false, _ -> Decimal input

    match value with
        | JsonValue.String  value -> BsonValue    (value)
        | JsonValue.Number  value -> match value with
                                        | Integer i -> BsonValue(i)
                                        | Decimal d -> BsonValue(d)
        | JsonValue.Float   value -> BsonValue    (value)
        | JsonValue.Boolean value -> BsonValue    (value)
        | JsonValue.Record  value -> BsonDocument (toBsonDictionary value) :> BsonValue
        | JsonValue.Array   value -> BsonArray    (toBsonArray      value) :> BsonValue
        | JsonValue.Null          -> BsonValue    ()

from https://github.com/UnoSD/WunderlistBackup

and deserializing is easy… JsonValue.Parse(bson.ToString()) although you may have to add some converters for types like long that get serialized as objects.

[Zaid-Ajaj]

@UnoSD I am glad you could figure it out, maybe you could share it for others who come across this issue 😃