patricksrobertson / secure_random.ex

Convenience library for random base64 strings modeled after my love for Ruby's SecureRandom

SecureRandom.ex

SecureRandom is an elixir module loosely based on Ruby's SecureRandom. I needed urlsafe, random, base64 strings and UUID generation, so I ported over what I needed :).

This gets its random from Erlang's strong_rand_bytes/1 and is strongly based from this gist. I had to remove some things that didn't make it to Elixir 1.0, and cut the stuff that I do not currently have use for.

Will accept PR's to flesh out further.

INSTALL

Add this to your mix.exs:

defp deps do
  [{:secure_random, "~> 0.5"}]
end

Fetch this motherlover:

mix deps.get

USAGE

UUID:

SecureRandom.uuid # => "e8bc6fde-3c11-cc2e-903b-745221154d8a"

base64 string:

SecureRandom.base64(8) # => "VsifwaD2HCk="

urlsafe_base64 string:

SecureRandom.urlsafe_base64 #=> "WAut546EWdXM3O_9sJGvmQ"

AUTHOR

Brought to you by Adequate Kitchen which is a vague way saying Patrick Robertson.

LICENSE

Apache 2.0

secure_random.ex's Issues

Length of returned hex string is not constant

When I execute SecureRandom.hex(12) multiple times, it returns quite often Strings with a length of 23 characters instead of 24 characters. I think this is not the expected behavior, as the Ruby counterpart returns strings with a constant size of the expected 24 characters.

iex(1)> SecureRandom.hex(12) |> String.length
24
iex(2)> SecureRandom.hex(12) |> String.length
24
iex(3)> SecureRandom.hex(12) |> String.length
24
iex(4)> SecureRandom.hex(12) |> String.length
23
iex(5)> SecureRandom.hex(12) |> String.length
24

urlsafe_base64 always ends in 09

Hi, I just noticed that urlsafe_base64 always ends in 09

UUID generated is not version 4

I noticed that the UUID being generated isn't following the UUID v4 schema.

This algorithm sets the version number (4 bits) as well as two reserved bits. All other bits (the remaining 122 bits) are set using a random or pseudorandom data source. Version 4 UUIDs have the form xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx where x is any hexadecimal digit and y is one of 8, 9, A, or B (e.g., f47ac10b-58cc-4372-a567-0e02b2c3d479).

For a conformant UUID v4 implementation, see the generate function in https://github.com/elixir-lang/ecto/blob/master/lib/ecto/uuid.ex