Elm: Json decoder timestamp to Date

Question

I\'m trying to convert a timestamp (ex: \"1493287973015\") from a JSON to a Date type.

So far I created this custom decoder:

stringToDate : Decoder Strin         


        

Answer 1

Two things, a JSON may actually have the milliseconds as an integer, not a string and things have changed since v 0.19 of Elm.

Given that your JSON looks something like.

{
    ...
    "someTime": 1552483995395,
    ...
}

Then this would decode to a Time.Posix:

import Json.Decode as Decode

decodeTime : Decode.Decoder Time.Posix
decodeTime =
    Decode.int
        |> Decode.andThen
            (\ms ->
                Decode.succeed <| Time.millisToPosix ms
            )