Trivial HMAC ruby pattern

gistfile1.rb

#!/usr/bin/env ruby

# http://ruby-doc.org/stdlib-2.1.5/libdoc/openssl/rdoc/OpenSSL/HMAC.html#method-c-digest

require 'openssl'

secret_key = 'secret_key'
digest_algo = 'sha1'

input_data = 'The quick brown fox jumps over the lazy dog'

digest1 = OpenSSL::Digest.new(digest_algo)
hmac1 = OpenSSL::HMAC.new(secret_key, digest1)

mac_hex_1 = hmac1.update(input_data).hexdigest
puts "HMAC code is <#{mac_hex_1}>"
hmac1.reset

### ---------------------

digest2 = OpenSSL::Digest.new(digest_algo)
hmac2 = OpenSSL::HMAC.new(secret_key, digest2)

output_data = input_data

mac_hex_2 = hmac2.update(output_data).hexdigest

valid = mac_hex_1 == mac_hex_2

puts "HMAC validity is <#{valid}> for HMAC code of <#{mac_hex_1}>"