util/id.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2017 Matthew Wild
   3 -- Copyright (C) 2008-2017 Waqas Hussain
   4 -- Copyright (C) 2008-2017 Kim Alvefur
   5 --
   6 -- This project is MIT/X11 licensed. Please see the
   7 -- COPYING file in the source package for more information.
   8 --
   9
  10 local s_gsub = string.gsub;
  11 local random_bytes = require "util.random".bytes;
  12 local base64_encode = require "util.encodings".base64.encode;
  13
  14 local b64url = { ["+"] = "-", ["/"] = "_", ["="] = "" };
  15 local function b64url_random(len)
  16         return (s_gsub(base64_encode(random_bytes(len)), "[+/=]", b64url));
  17 end
  18
  19 return {
  20         short =  function () return b64url_random(6); end;
  21         medium = function () return b64url_random(12); end;
  22         long =   function () return b64url_random(24); end;
  23         custom = function (size)
  24                 return function () return b64url_random(size); end;
  25         end;
  26 }