let tryUploadFileAsync fileType =
  async {
    match fileType with
    | "image" -> return Some 1L
    | "uploading_not_required" -> return None
    | _ -> return failwithf "%s uploading is not supported" fileType
  }

module Async =
  let map f x = async.Bind(x, f >> async.Return)

let files = []

let maybeAsyncUploadedFiles =
  files
  |> Seq.map tryUploadFileAsync
  |> Async.Sequential
  |> Async.Catch
  |> Async.map (function
    | Choice1Of2 allIdList -> ()
    | Choice2Of2 error -> ()
  )