niftycloud-describe-Instances.rb

#! /usr/bin/env ruby
# NIFTY Cloud API - DescribeInstances
# Author::    Kei HAMANAKA <kei.hamanaka (at) gmail.com>
# License::   Distributes under the same terms as Ruby

require 'uri'
require 'time'
require 'net/https'
require 'cgi'
require 'openssl'

ACCESS_KEY        = ""
SECRET_ACCESS_KEY = ""

class NIFTYCloud
  REQUEST_URI_BASE  = URI.parse('https://cp.cloud.nifty.com/api/')
  SIGNATURE_VERSION = 0
  API_VERSION       = 1.5
  TIME_STAMP        = Time.now.utc.iso8601
  ACTION_NAME       = "DescribeInstances"

  def initialize(access_key, secret_access_key)
    @access_key        = access_key
    @secret_access_key = secret_access_key
  end

  def describe_instances
    request(create_path)
  end

  private

  def request(path)
    https = Net::HTTP.new(REQUEST_URI_BASE.host, REQUEST_URI_BASE.port)
    https.use_ssl = true
    https.verify_mode = OpenSSL::SSL::VERIFY_NONE
    https.start do |request|
      response = request.get(path)
      response.body
    end
  end

  def create_path
    [REQUEST_URI_BASE.path, create_parameters].join("?")
  end

  def create_parameters
    signature  = create_signature(ACTION_NAME, @secret_access_key, TIME_STAMP)
    create_params(@access_key, SIGNATURE_VERSION, signature,
                  API_VERSION, TIME_STAMP, ACTION_NAME
                  ).join("&")
  end

  def create_signature(action_name, secret_access_key, time_stamp)
    signature = action_name + time_stamp.to_s
    base64(digest_hmac_sha1(secret_access_key, signature))
  end

  def digest_hmac_sha1(secret_access_key, value)
    OpenSSL::HMAC.digest(OpenSSL::Digest::SHA1.new, secret_access_key, value)
  end

  def base64(value)
    [ value ].pack('m').strip!
  end

  def create_params(access_key, signature_version, signature,
                    api_version, time_stamp, action_name)
    params = {
      "AccessKeyId" => access_key,
      "Action" => action_name,
      "SignatureVersion" => signature_version,
      "Signature" => signature,
      "Version"   => api_version,
      "Timestamp" => time_stamp
    }
    encode_params(params)
  end

  def encode_params(params)
    params.collect do |k, v|
      encoded = (CGI.escape(k.to_s) +
                 "=" + CGI.escape(v.to_s))
      encoded = encoded.gsub('+', '%20')
      encoded = encoded.gsub('%7E', '~')
    end
  end
end

niftycloud = NIFTYCloud.new(ACCESS_KEY, SECRET_ACCESS_KEY)
puts niftycloud.describe_instances