Generate Random Strings in Ruby

require 'securerandom'

def generate_random_string(length = 16, custom_chars = nil)
  chars = custom_chars || ('a'..'z').to_a + ('A'..'Z').to_a + ('0'..'9').to_a

  Array.new(length) { chars[SecureRandom.random_number(chars.length)] }.join
end

# Generate a 16-character alphanumeric string
random_string = generate_random_string(16)
puts random_string  # Example: aB3xY7mN2pQ9zR5t

# Generate a 12-character hex string
hex_string = generate_random_string(12, ('0'..'9').to_a + ('a'..'f').to_a)
puts hex_string  # Example: a3f7b2e9c4d1

# Generate a 10-character lowercase string
lowercase_string = generate_random_string(10, ('a'..'z').to_a)
puts lowercase_string  # Example: xmkpqrstuv

# Alternative: use built-in methods
hex_token = SecureRandom.hex(8)  # 16 hex characters
puts hex_token

urlsafe_token = SecureRandom.urlsafe_base64(12)
puts urlsafe_token