Attempt to generate a compressed public key from EC private key

compressed_public_key.rb

#!/usr/bin/env ruby
require 'bundler/inline'
gemfile do
  gem "openssl"
end

# See https://github.com/ruby/openssl/issues/29
def real_public_key(k)
  # TODO? .point_conversion_form = :compressed
  point = k.public_key
  pub = OpenSSL::PKey::EC.new(point.group)
  pub.public_key = point
  pub
end

ec1 = OpenSSL::PKey::EC.new('secp256k1').generate_key

# Write a file to file to covert it via the CLI
File.open("test-compressed-key.pem", 'w') {|f| f.write(ec1.to_pem) }

# CLI Version:
puts `openssl ec -in test-compressed-key.pem  -pubout -conv_form compressed`

# Ruby Version:
puts real_public_key(ec1).to_pem