IronFunctions help Seif Lotfy

ironfunctions.test.fs

// code converted for http://seif.codes/playing-with-net-dotnet-and-ironfunctions/
// https://twitter.com/SeifLotfy/status/805901527659540480

open System
open System.IO
open System.Security.Cryptography
open System.Text

let downloadRemoteImageFile (url: string) =
  let request = url |> System.Net.WebRequest.CreateHttp
  use response = request.GetResponseAsync().Result
  use stream = response.GetResponseStream()
  use memoryStream = new MemoryStream(Capacity = int response.ContentLength)
  stream.CopyTo memoryStream
  memoryStream.ToArray()

let isPipedInput () =
  try
    let _ = Console.KeyAvailable
    false
  with
  | _ -> true

let createCheckSum (data: byte array) =
  use md5 = MD5.Create()
  let hash = md5.ComputeHash data
  let builder = StringBuilder()
  for b in hash do
    sprintf "%x" b |> (builder.Append >> ignore)
  builder.ToString()

[<EntryPoint>]
let main args =
  if not (isPipedInput()) then
    1
  else
    Console.In.ReadToEnd()
    |> downloadRemoteImageFile
    |> createCheckSum
    |> Console.WriteLine

    0