Elm: File Upload Request

FileUploadRequest.elm

doUploadFile : Maybe AuthToken -> String -> File -> (Result Http.Error UploadedFile -> msg) ->  Cmd msg
doUploadFile mbToken name file msg  =
    Http.request
        { method = "PUT"
        , headers = [Http.header "Authorization" <| "Bearer " ++ (tokenToString mbToken)]
        , url = "api/upload"
        , body =
            Http.multipartBody
                [ Http.stringPart "name" name
                , Http.filePart "file" file
                ]
        , expect = Http.expectJson msg uploadedFileDecoder
        , timeout = Nothing
        , tracker = Just (File.name file)
        }