Add a generator of a SafeString.

CHANGELOG.org

@@ -7,4 +7,6 @@
     Updated the Links model to have a unique shorten.
 ** 0.1.2 <2023-07-06 Thu>
     Renamed the Links.get_one_by_name to get_one_by_shorten.
+** 0.2.0 <2023-07-07 Fri>
+    Added a generator of a SafeString.
 

lib/link_shortener/generators/safe_string.ex

@@ -0,0 +1,15 @@
+defmodule LinkShortener.Generators.SafeString do
+  @moduledoc """
+  This module provides a generator.
+  """
+
+  @doc """
+  Generate a random string with the length.
+  The string can be used as part of a url.
+  """
+  def generate(length) do
+    :crypto.strong_rand_bytes(length)
+    |> Base.url_encode64()
+    |> binary_part(0, length)
+  end
+end