gem 'sip2'

client = Sip2::Client.new(host: 'my.sip2.host.net', port: 6001)
patron =
  client.connect do |connection|
    if connection.login 'sip_username', 'sip_password'
      connection.patron_information 'patron_username', 'patron_password'
    end
  end

puts 'Valid patron' if patron && patron.authenticated?

# Setup a cert store using the system certificates/trust chain
cert_store = OpenSSL::X509::Store.new
cert_store.set_default_paths

# Setup the SSL context
ssl_context = OpenSSL::SSL::SSLContext.new
ssl_context.verify_mode = OpenSSL::SSL::VERIFY_PEER # This is important. We want to verify the certificate is legitimate 
ssl_context.min_version = OpenSSL::SSL::TLS1_2_VERSION # Generally good practice to enforce the most recent TLS version
ssl_context.cert_store = cert_store # Use the certificate store we configured above

# Raise an exception if the certificate doesn't check out
ssl_context.verify_callback = proc do |preverify_ok, context|
  raise OpenSSL::SSL::SSLError, <<~ERROR.strip if preverify_ok != true || context.error != 0
    SSL Verification failed -- Preverify: #{preverify_ok}, Error: #{context.error_string} (#{context.error})
  ERROR

  true
end

client = Sip2::Client.new(host: 'my.sip2.host.net', port: 6001, ssl_context: ssl_context)