# -*- coding: utf-8 -*-
#
# Copyright (c) 2007-2008 RightScale Inc
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#

module Aws

  # = Aws::EC2 -- RightScale Amazon EC2 interface
  # The Aws::EC2 class provides a complete interface to Amazon's
  # Elastic Compute Cloud service, as well as the associated EBS (Elastic Block
  # Store).
  # For explanations of the semantics
  # of each call, please refer to Amazon's documentation at
  # http://developer.amazonwebservices.com/connect/kbcategory.jspa?categoryID=87
  #
  # Examples:
  #
  # Create an EC2 interface handle:
  #
  #   @ec2   = Aws::Ec2.new(aws_access_key_id,
  #                               aws_secret_access_key)
  # Create a new SSH key pair:
  #  @key   = 'right_ec2_awesome_test_key'
  #  new_key = @ec2.create_key_pair(@key)
  #  keys = @ec2.describe_key_pairs
  #
  # Create a security group:
  #  @group = 'right_ec2_awesome_test_security_group'
  #  @ec2.create_security_group(@group,'My awesome test group')
  #  group = @ec2.describe_security_groups([@group])[0]
  #
  # Configure a security group:
  #  @ec2.authorize_security_group_named_ingress(@group, account_number, 'default')
  #  @ec2.authorize_security_group_IP_ingress(@group, 80,80,'udp','192.168.1.0/8')
  #
  # Describe the available images:
  #  images = @ec2.describe_images
  #
  # Launch an instance:
  #  ec2.run_instances('ami-9a9e7bf3', 1, 1, ['default'], @key, 'SomeImportantUserData', 'public')
  #
  #
  # Describe running instances:
  #  @ec2.describe_instances
  #
  # Error handling: all operations raise an Aws::AwsError in case
  # of problems. Note that transient errors are automatically retried.

  class Ec2 < AwsBase
    include AwsBaseInterface

    # Amazon EC2 API version being used
    API_VERSION             = "2010-08-31"
    DEFAULT_HOST            = "ec2.amazonaws.com"
    DEFAULT_PATH            = '/'
    DEFAULT_PROTOCOL        = 'https'
    DEFAULT_PORT            = 443

    # Default addressing type (public=NAT, direct=no-NAT) used when launching instances.
    DEFAULT_ADDRESSING_TYPE = 'public'
    DNS_ADDRESSING_SET      = ['public', 'direct']

    # Amazon EC2 Instance Types : http://www.amazon.com/b?ie=UTF8&node=370375011
    # Default EC2 instance type (platform)
    DEFAULT_INSTANCE_TYPE   = 'm1.small'
    INSTANCE_TYPES          = ['t1.micro', 'm1.small', 'c1.medium', 'm1.large', 'm1.xlarge', 'c1.xlarge']

    def self.connection_name
      :ec2_connection
    end

    @@bench                 = AwsBenchmarkingBlock.new
    def self.bench
      @@bench
    end

    def self.bench_xml
      @@bench.xml
    end

    def self.bench_ec2
      @@bench.service
    end

    # Current API version (sometimes we have to check it outside the GEM).
    @@api = ENV['EC2_API_VERSION'] || API_VERSION

    def self.api
      @@api
    end

    # Create a new handle to an EC2 account. All handles share the same per process or per thread
    # HTTP connection to Amazon EC2. Each handle is for a specific account. The params have the
    # following options:
    # * <tt>:endpoint_url</tt> a fully qualified url to Amazon API endpoint (this overwrites: :server, :port, :service, :protocol and :region). Example: 'https://eu-west-1.ec2.amazonaws.com/'
    # * <tt>:server</tt>: EC2 service host, default: DEFAULT_HOST
    # * <tt>:region</tt>: EC2 region (North America by default)
    # * <tt>:port</tt>: EC2 service port, default: DEFAULT_PORT
    # * <tt>:protocol</tt>: 'http' or 'https', default: DEFAULT_PROTOCOL
    # * <tt>:multi_thread</tt>: true=HTTP connection per thread, false=per process
    # * <tt>:logger</tt>: for log messages, default: Rails.logger else STDOUT
    # * <tt>:signature_version</tt>:  The signature version : '0' or '1'(default)
    # * <tt>:cache</tt>: true/false: caching for: ec2_describe_images, describe_instances,
    # describe_images_by_owner, describe_images_by_executable_by, describe_availability_zones,
    # describe_security_groups, describe_key_pairs, describe_addresses,
    # describe_volumes, describe_snapshots methods, default: false.
    #
    def initialize(aws_access_key_id=nil, aws_secret_access_key=nil, params={})
      init({:name             => 'EC2',
            :default_host     => ENV['EC2_URL'] ? URI.parse(ENV['EC2_URL']).host : DEFAULT_HOST,
            :default_port     => ENV['EC2_URL'] ? URI.parse(ENV['EC2_URL']).port : DEFAULT_PORT,
            :default_service  => ENV['EC2_URL'] ? URI.parse(ENV['EC2_URL']).path : DEFAULT_PATH,
            :default_protocol => ENV['EC2_URL'] ? URI.parse(ENV['EC2_URL']).scheme : DEFAULT_PROTOCOL,
            :api_version      => API_VERSION},
           aws_access_key_id || ENV['AWS_ACCESS_KEY_ID'],
           aws_secret_access_key|| ENV['AWS_SECRET_ACCESS_KEY'],
           params)
      # EC2 doesn't really define any transient errors to retry, and in fact,
      # when they return a 503 it is usually for 'request limit exceeded' which
      # we most certainly should not retry.  So let's pare down the list of
      # retryable errors to InternalError only (see AwsBase for the default
      # list)
      amazon_problems = ['InternalError']
    end


    def generate_request(action, params={}) #:nodoc:
      service_hash = {"Action"         => action,
                      "AWSAccessKeyId" => @aws_access_key_id,
                      "Version"        => @@api}
      service_hash.update(params)
      service_params = signed_service_params(@aws_secret_access_key, service_hash, :get, @params[:server], @params[:service])

      # use POST method if the length of the query string is too large
      if service_params.size > 2000
        if signature_version == '2'
          # resign the request because HTTP verb is included into signature
          service_params = signed_service_params(@aws_secret_access_key, service_hash, :post, @params[:server], @params[:service])
        end
        request                 = Net::HTTP::Post.new(@params[:service])
        request.body            = service_params
        request['Content-Type'] = 'application/x-www-form-urlencoded'
      else
        request = Net::HTTP::Get.new("#{@params[:service]}?#{service_params}")
      end
      # prepare output hash
      {:request  => request,
       :server   => @params[:server],
       :port     => @params[:port],
       :protocol => @params[:protocol]}
    end

    # Sends request to Amazon and parses the response
    # Raises AwsError if any banana happened
    # todo: remove this and switch to using request_info2
    def request_info(request, parser, options={}) #:nodoc:
      conn = get_conn(self.class.connection_name, @params, @logger)
      request_info_impl(conn, @@bench, request, parser, options)
    end

    def hash_params(prefix, list) #:nodoc:
      groups = {}
      list.each_index { |i| groups.update("#{prefix}.#{i+1}"=>list[i]) } if list
      return groups
    end

    def hash_params_with_suffix(prefix, suffix, list) #:nodoc:
      groups = {}
      list.each_index { |i| groups.update("#{prefix}.#{i+1}.suffix"=>list[i]) }
      return groups
    end

    #-----------------------------------------------------------------
    #      Images
    #-----------------------------------------------------------------

    # params:
    #   { 'ImageId'      => ['id1', ..., 'idN'],
    #     'Owner'        => ['self', ..., 'userN'],
    #     'ExecutableBy' => ['self', 'all', ..., 'userN']
    #   }
    def ec2_describe_images(params={}, image_type=nil, cache_for=nil) #:nodoc:
      request_hash = {}
      params.each do |list_by, list|
        request_hash.merge! hash_params(list_by, list.to_a)
      end
      if image_type
        request_hash['Filter.1.Name']    = "image-type"
        request_hash['Filter.1.Value.1'] = image_type
      end
      link = generate_request("DescribeImages", request_hash)
      request_cache_or_info cache_for, link, QEc2DescribeImagesParser, @@bench, cache_for
    rescue Exception
      on_exception
    end

    # Retrieve a list of images. Returns array of hashes describing the images or an exception:
    # +image_type+ = 'machine' || 'kernel' || 'ramdisk'
    #
    #  ec2.describe_images #=>
    #    [{:aws_owner => "522821470517",
    #      :aws_id => "ami-e4b6538d",
    #      :aws_state => "available",
    #      :aws_location => "marcins_cool_public_images/ubuntu-6.10.manifest.xml",
    #      :aws_is_public => true,
    #      :aws_architecture => "i386",
    #      :aws_image_type => "machine"},
    #     {...},
    #     {...} ]
    #
    # If +list+ param is set, then retrieve information about the listed images only:
    #
    #  ec2.describe_images(['ami-e4b6538d']) #=>
    #    [{:aws_owner => "522821470517",
    #      :aws_id => "ami-e4b6538d",
    #      :aws_state => "available",
    #      :aws_location => "marcins_cool_public_images/ubuntu-6.10.manifest.xml",
    #      :aws_is_public => true,
    #      :aws_architecture => "i386",
    #      :aws_image_type => "machine"}]
    #
    def describe_images(list=[], image_type=nil)
      list      = list.to_a
      cache_for = list.empty? && !image_type ? :describe_images : nil
      ec2_describe_images({'ImageId' => list}, image_type, cache_for)
    end

    #
    #  Example:
    #
    #   ec2.describe_images_by_owner('522821470517')
    #   ec2.describe_images_by_owner('self')
    #
    def describe_images_by_owner(list=['self'], image_type=nil)
      list      = list.to_a
      cache_for = list==['self'] && !image_type ? :describe_images_by_owner : nil
      ec2_describe_images({'Owner' => list}, image_type, cache_for)
    end

    #
    #  Example:
    #
    #   ec2.describe_images_by_executable_by('522821470517')
    #   ec2.describe_images_by_executable_by('self')
    #   ec2.describe_images_by_executable_by('all')
    #
    def describe_images_by_executable_by(list=['self'], image_type=nil)
      list      = list.to_a
      cache_for = list==['self'] && !image_type ? :describe_images_by_executable_by : nil
      ec2_describe_images({'ExecutableBy' => list}, image_type, cache_for)
    end


    # Register new image at Amazon.
    # Returns new image id or an exception.
    #
    #  ec2.register_image('bucket/key/manifest') #=> 'ami-e444444d'
    #
    def register_image(image_location)
      link = generate_request("RegisterImage",
                              'ImageLocation' => image_location.to_s)
      request_info(link, QEc2RegisterImageParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Deregister image at Amazon. Returns +true+ or an exception.
    #
    #  ec2.deregister_image('ami-e444444d') #=> true
    #
    def deregister_image(image_id)
      link = generate_request("DeregisterImage",
                              'ImageId' => image_id.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end


    # Describe image attributes. Currently 'launchPermission', 'productCodes', 'kernel', 'ramdisk' and 'blockDeviceMapping'  are supported.
    #
    #  ec2.describe_image_attribute('ami-e444444d') #=> {:groups=>["all"], :users=>["000000000777"]}
    #
    def describe_image_attribute(image_id, attribute='launchPermission')
      link = generate_request("DescribeImageAttribute",
                              'ImageId'   => image_id,
                              'Attribute' => attribute)
      request_info(link, QEc2DescribeImageAttributeParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Reset image attribute. Currently, only 'launchPermission' is supported. Returns +true+ or an exception.
    #
    #  ec2.reset_image_attribute('ami-e444444d') #=> true
    #
    def reset_image_attribute(image_id, attribute='launchPermission')
      link = generate_request("ResetImageAttribute",
                              'ImageId'   => image_id,
                              'Attribute' => attribute)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Modify an image's attributes. It is recommended that you use
    # modify_image_launch_perm_add_users, modify_image_launch_perm_remove_users, etc.
    # instead of modify_image_attribute because the signature of
    # modify_image_attribute may change with EC2 service changes.
    #
    #  operation_type : currently, only 'Add' & 'Remove' are supported.
    #  vars:
    #    :user_group  : currently, only 'all' is supported.
    #    :user_id
    #    :product_code
    #    :description
    def modify_image_attribute(image_id, operation_type = nil, vars = {})
      params = {'ImageId' => image_id }
      params.update(hash_params_with_suffix("LaunchPermission.#{operation_type}", 'UserId', vars[:user_id].to_a)) if vars[:user_id]
      params.update(hash_params_with_suffix("LaunchPermission.#{operation_type}", 'Group', vars[:user_group].to_a)) if vars[:user_group]
      params.update(hash_params('ProductCode', vars[:product_code])) if vars[:product_code]
      params.update('Description.Value' => vars[:description].to_s) if vars[:description]
      link = generate_request("ModifyImageAttribute", params)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Grant image launch permissions to users.
    # Parameter +userId+ is a list of user AWS account ids.
    # Returns +true+ or an exception.
    #
    #  ec2.modify_image_launch_perm_add_users('ami-e444444d',['000000000777','000000000778']) #=> true
    def modify_image_launch_perm_add_users(image_id, user_id=[])
      modify_image_attribute(image_id, 'Add', :user_id => user_id.to_a)
    end

    # Revokes image launch permissions for users. +userId+ is a list of users AWS accounts ids. Returns +true+ or an exception.
    #
    #  ec2.modify_image_launch_perm_remove_users('ami-e444444d',['000000000777','000000000778']) #=> true
    #
    def modify_image_launch_perm_remove_users(image_id, user_id=[])
      modify_image_attribute(image_id, 'Remove', :user_id => user_id.to_a)
    end

    # Add image launch permissions for users groups (currently only 'all' is supported, which gives public launch permissions).
    # Returns +true+ or an exception.
    #
    #  ec2.modify_image_launch_perm_add_groups('ami-e444444d') #=> true
    #
    def modify_image_launch_perm_add_groups(image_id, user_group=['all'])
      modify_image_attribute(image_id, 'Add', :user_group => user_group.to_a)
    end

    # Remove image launch permissions for users groups (currently only 'all' is supported, which gives public launch permissions).
    #
    #  ec2.modify_image_launch_perm_remove_groups('ami-e444444d') #=> true
    #
    def modify_image_launch_perm_remove_groups(image_id, user_group=['all'])
      modify_image_attribute(image_id, 'Remove', :user_group => user_group.to_a)
    end

    # Add product code to image
    #
    #  ec2.modify_image_product_code('ami-e444444d','0ABCDEF') #=> true
    #
    def modify_image_product_code(image_id, product_code=[])
      modify_image_attribute(image_id, nil, :product_code => product_code.to_a)
    end

    # Change image description
    #
    #  ec2.modify_image_description('ami-e444444d','My new AMI') #=> true
    #
    def modify_image_description(image_id, description='')
      modify_image_attribute(image_id, nil, :description => description)
    end

    #-----------------------------------------------------------------
    #      Instances
    #-----------------------------------------------------------------

    def get_desc_instances(instances) # :nodoc:
      result = []
      instances.each do |reservation|
        reservation[:instances_set].each do |instance|
          # Parse and remove timestamp from the reason string. The timestamp is of
          # the request, not when EC2 took action, thus confusing & useless...
          instance[:aws_reason]         = instance[:aws_reason].sub(/\(\d[^)]*GMT\) */, '')
          instance[:aws_owner]          = reservation[:aws_owner]
          instance[:aws_reservation_id] = reservation[:aws_reservation_id]
          instance[:aws_groups]         = reservation[:aws_groups]
          result << instance
        end
      end
      result
    rescue Exception
      on_exception
    end

    # Retrieve information about EC2 instances. If +list+ is omitted then returns the
    # list of all instances.
    #
    #  ec2.describe_instances #=>
    #    [{:aws_image_id       => "ami-e444444d",
    #      :aws_reason         => "",
    #      :aws_state_code     => "16",
    #      :aws_owner          => "000000000888",
    #      :aws_instance_id    => "i-123f1234",
    #      :aws_reservation_id => "r-aabbccdd",
    #      :aws_state          => "running",
    #      :dns_name           => "domU-12-34-67-89-01-C9.usma2.compute.amazonaws.com",
    #      :ssh_key_name       => "staging",
    #      :aws_groups         => ["default"],
    #      :private_dns_name   => "domU-12-34-67-89-01-C9.usma2.compute.amazonaws.com",
    #      :aws_instance_type  => "m1.small",
    #      :aws_launch_time    => "2008-1-1T00:00:00.000Z"},
    #      :aws_availability_zone => "us-east-1b",
    #      :aws_kernel_id      => "aki-ba3adfd3",
    #      :aws_ramdisk_id     => "ari-badbad00",
    #      :monitoring_state         => ...,
    #       ..., {...}]
    #
    def describe_instances(list=[])
      link = generate_request("DescribeInstances", hash_params('InstanceId', list.to_a))
      request_cache_or_info(:describe_instances, link, QEc2DescribeInstancesParser, @@bench, list.nil? || list.empty?) do |parser|
        get_desc_instances(parser.result)
      end
    rescue Exception
      on_exception
    end

    # Return the product code attached to instance or +nil+ otherwise.
    #
    #  ec2.confirm_product_instance('ami-e444444d','12345678') #=> nil
    #  ec2.confirm_product_instance('ami-e444444d','00001111') #=> "000000000888"
    #
    def confirm_product_instance(instance, product_code)
      link = generate_request("ConfirmProductInstance", {'ProductCode' => product_code,
                                                         'InstanceId'  => instance})
      request_info(link, QEc2ConfirmProductInstanceParser.new(:logger => @logger))
    end

    # DEPRECATED, USE launch_instances instead.
    #
    # Launch new EC2 instances. Returns a list of launched instances or an exception.
    #
    #  ec2.run_instances('ami-e444444d',1,1,['my_awesome_group'],'my_awesome_key', 'Woohoo!!!', 'public') #=>
    #   [{:aws_image_id       => "ami-e444444d",
    #     :aws_reason         => "",
    #     :aws_state_code     => "0",
    #     :aws_owner          => "000000000888",
    #     :aws_instance_id    => "i-123f1234",
    #     :aws_reservation_id => "r-aabbccdd",
    #     :aws_state          => "pending",
    #     :dns_name           => "",
    #     :ssh_key_name       => "my_awesome_key",
    #     :aws_groups         => ["my_awesome_group"],
    #     :private_dns_name   => "",
    #     :aws_instance_type  => "m1.small",
    #     :aws_launch_time    => "2008-1-1T00:00:00.000Z"
    #     :aws_ramdisk_id     => "ari-8605e0ef"
    #     :aws_kernel_id      => "aki-9905e0f0",
    #     :ami_launch_index   => "0",
    #     :aws_availability_zone => "us-east-1b"
    #     }]
    #
    def run_instances(image_id, min_count, max_count, group_ids, key_name, user_data='',
        addressing_type = nil, instance_type = nil,
        kernel_id = nil, ramdisk_id = nil, availability_zone = nil,
        block_device_mappings = nil)
      launch_instances(image_id, {:min_count             => min_count,
                                  :max_count             => max_count,
                                  :user_data             => user_data,
                                  :group_ids             => group_ids,
                                  :key_name              => key_name,
                                  :instance_type         => instance_type,
                                  :addressing_type       => addressing_type,
                                  :kernel_id             => kernel_id,
                                  :ramdisk_id            => ramdisk_id,
                                  :availability_zone     => availability_zone,
                                  :block_device_mappings => block_device_mappings
      })
    end


    # Launch new EC2 instances. Returns a list of launched instances or an exception.
    #
    # +lparams+ keys (default values in parenthesis):
    #  :min_count              fixnum, (1)
    #  :max_count              fixnum, (1)
    #  :group_ids              array or string ([] == 'default')
    #  :instance_type          string (DEFAULT_INSTACE_TYPE)
    #  :addressing_type        string (DEFAULT_ADDRESSING_TYPE
    #  :key_name               string
    #  :kernel_id              string
    #  :ramdisk_id             string
    #  :availability_zone      string
    #  :block_device_mappings  string
    #  :user_data              string
    #  :monitoring_enabled     boolean (default=false)
    #
    #  ec2.launch_instances('ami-e444444d', :group_ids => 'my_awesome_group',
    #                                       :user_data => "Woohoo!!!",
    #                                       :addressing_type => "public",
    #                                       :key_name => "my_awesome_key",
    #                                       :availability_zone => "us-east-1c") #=>
    #   [{:aws_image_id       => "ami-e444444d",
    #     :aws_reason         => "",
    #     :aws_state_code     => "0",
    #     :aws_owner          => "000000000888",
    #     :aws_instance_id    => "i-123f1234",
    #     :aws_reservation_id => "r-aabbccdd",
    #     :aws_state          => "pending",
    #     :dns_name           => "",
    #     :ssh_key_name       => "my_awesome_key",
    #     :aws_groups         => ["my_awesome_group"],
    #     :private_dns_name   => "",
    #     :aws_instance_type  => "m1.small",
    #     :aws_launch_time    => "2008-1-1T00:00:00.000Z",
    #     :aws_ramdisk_id     => "ari-8605e0ef"
    #     :aws_kernel_id      => "aki-9905e0f0",
    #     :ami_launch_index   => "0",
    #     :aws_availability_zone => "us-east-1c"
    #     }]
    #
    def launch_instances(image_id, options={})
      @logger.info("Launching instance of image #{image_id}, " +
                       "key: #{options[:key_name]}, groups: #{(options[:group_ids]).to_a.join(',')}")
      # careful: keyName and securityGroups may be nil
      params = hash_params('SecurityGroup', options[:group_ids].to_a)
      params.update({'ImageId'        => image_id,
                     'MinCount'       => (options[:min_count] || 1).to_s,
                     'MaxCount'       => (options[:max_count] || 1).to_s,
                     'AddressingType' => options[:addressing_type] || DEFAULT_ADDRESSING_TYPE,
                     'InstanceType'   => options[:instance_type] || DEFAULT_INSTANCE_TYPE})
      # optional params
      params.merge!(hash_params('SecurityGroupId',options[:SecurityGroupId].to_a)) unless Aws::Utils.blank?(options[:SecurityGroupId])
      params['KeyName'] = options[:key_name] unless Aws::Utils.blank?(options[:key_name])
      params['KernelId'] = options[:kernel_id] unless Aws::Utils.blank?(options[:kernel_id])
      params['RamdiskId'] = options[:ramdisk_id] unless Aws::Utils.blank?(options[:ramdisk_id])
      params['Placement.AvailabilityZone'] = options[:availability_zone] unless Aws::Utils.blank?(options[:availability_zone])
      params['BlockDeviceMappings'] = options[:block_device_mappings] unless Aws::Utils.blank?(options[:block_device_mappings])
      params['Monitoring.Enabled'] = options[:monitoring_enabled] unless Aws::Utils.blank?(options[:monitoring_enabled])
      params['SubnetId'] = options[:subnet_id] unless Aws::Utils.blank?(options[:subnet_id])
      params['AdditionalInfo'] = options[:additional_info] unless Aws::Utils.blank?(options[:additional_info])
      params['DisableApiTermination'] = options[:disable_api_termination].to_s unless options[:disable_api_termination].nil?
      params['InstanceInitiatedShutdownBehavior'] = options[:instance_initiated_shutdown_behavior] unless Aws::Utils.blank?(options[:instance_initiated_shutdown_behavior])
      unless Aws::Utils.blank?(options[:user_data])
        options[:user_data].strip!
        # Do not use CGI::escape(encode64(...)) as it is done in Amazons EC2 library.
        # Amazon 169.254.169.254 does not like escaped symbols!
        # And it doesn't like "\n" inside of encoded string! Grrr....
        # Otherwise, some of UserData symbols will be lost...
        params['UserData'] = Base64.encode64(options[:user_data]).delete("\n").strip unless Aws::Utils.blank?(options[:user_data])
      end
      unless Aws::Utils.blank?(options[:block_device_mappings])
        options[:block_device_mappings].size.times do |n|
          if options[:block_device_mappings][n][:virtual_name]
            params["BlockDeviceMapping.#{n+1}.VirtualName"] = options[:block_device_mappings][n][:virtual_name]
          end
          if options[:block_device_mappings][n][:device_name]
            params["BlockDeviceMapping.#{n+1}.DeviceName"] = options[:block_device_mappings][n][:device_name]
          end
          if options[:block_device_mappings][n][:ebs_snapshot_id]
            params["BlockDeviceMapping.#{n+1}.Ebs.SnapshotId"] = options[:block_device_mappings][n][:ebs_snapshot_id]
          end
        end
      end
      link      = generate_request("RunInstances", params)
      #debugger
      instances = request_info(link, QEc2DescribeInstancesParser.new(:logger => @logger))
      get_desc_instances(instances)
    rescue Exception
      on_exception
    end

    def monitor_instances(list=[])
      link = generate_request("MonitorInstances", hash_params('InstanceId', list.to_a))
      request_info(link, QEc2TerminateInstancesParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Terminates EC2 instances. Returns a list of termination params or an exception.
    #
    #  ec2.terminate_instances(['i-f222222d','i-f222222e']) #=>
    #    [{:aws_shutdown_state      => "shutting-down",
    #      :aws_instance_id         => "i-f222222d",
    #      :aws_shutdown_state_code => 32,
    #      :aws_prev_state          => "running",
    #      :aws_prev_state_code     => 16},
    #     {:aws_shutdown_state      => "shutting-down",
    #      :aws_instance_id         => "i-f222222e",
    #      :aws_shutdown_state_code => 32,
    #      :aws_prev_state          => "running",
    #      :aws_prev_state_code     => 16}]
    #
    def terminate_instances(list=[])
      link = generate_request("TerminateInstances", hash_params('InstanceId', list.to_a))
      request_info(link, QEc2TerminateInstancesParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Stop EBS-backed EC2 instances. Returns a list of instance state changes or an exception.
    #
    #  ec2.stop_instances(['i-f222222d', 'i-f222222e']) #=>
    #    [{:aws_instance_id         => "i-f222222d",
    #      :aws_current_state_code  => 64,
    #      :aws_current_state       => "stopping",
    #      :aws_prev_state_code     => 16,
    #      :aws_prev_state          => "running"},
    #     {:aws_instance_id         => "i-f222222e",
    #      :aws_current_state_code  => 64,
    #      :aws_current_state       => "stopping",
    #      :aws_prev_state_code     => 16,
    #      :aws_prev_state          => "running"}]
    #
    def stop_instances(list=[])
      link = generate_request("StopInstances", hash_params('InstanceId', list.to_a))
      request_info(link, QEc2StopInstancesParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Start EBS-backed EC2 instances. Returns a list of instance state changes or an exception.
    #
    #  ec2.start_instances(['i-f222222d', 'i-f222222e']) #=>
    #    [{:aws_instance_id         => "i-f222222d",
    #      :aws_current_state_code  => 0,
    #      :aws_current_state       => "pending",
    #      :aws_prev_state_code     => 80,
    #      :aws_prev_state          => "stopped"},
    #     {:aws_instance_id         => "i-f222222e",
    #      :aws_current_state_code  => 0,
    #      :aws_current_state       => "pending",
    #      :aws_prev_state_code     => 80,
    #      :aws_prev_state          => "stopped"}]
    #
    def start_instances(list=[])
      link = generate_request("StartInstances", hash_params('InstanceId', list.to_a))
      request_info(link, QEc2StartInstancesParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Retreive EC2 instance OS logs. Returns a hash of data or an exception.
    #
    #  ec2.get_console_output('i-f222222d') =>
    #    {:aws_instance_id => 'i-f222222d',
    #     :aws_timestamp   => "2007-05-23T14:36:07.000-07:00",
    #     :timestamp       => Wed May 23 21:36:07 UTC 2007,          # Time instance
    #     :aws_output      => "Linux version 2.6.16-xenU (builder@patchbat.amazonsa) (gcc version 4.0.1 20050727 ..."
    def get_console_output(instance_id)
      link = generate_request("GetConsoleOutput", {'InstanceId.1' => instance_id})
      request_info(link, QEc2GetConsoleOutputParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Reboot an EC2 instance. Returns +true+ or an exception.
    #
    #  ec2.reboot_instances(['i-f222222d','i-f222222e']) #=> true
    #
    def reboot_instances(list)
      link = generate_request("RebootInstances", hash_params('InstanceId', list.to_a))
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    #-----------------------------------------------------------------
    #      Instances: Windows addons
    #-----------------------------------------------------------------

    # Get initial Windows Server setup password from an instance console output.
    #
    #  my_awesome_key = ec2.create_key_pair('my_awesome_key') #=>
    #    {:aws_key_name    => "my_awesome_key",
    #     :aws_fingerprint => "01:02:03:f4:25:e6:97:e8:9b:02:1a:26:32:4e:58:6b:7a:8c:9f:03",
    #     :aws_material    => "-----BEGIN RSA PRIVATE KEY-----\nMIIEpQIBAAK...Q8MDrCbuQ=\n-----END RSA PRIVATE KEY-----"}
    #
    #  my_awesome_instance = ec2.run_instances('ami-a000000a',1,1,['my_awesome_group'],'my_awesome_key', 'WindowsInstance!!!') #=>
    #   [{:aws_image_id       => "ami-a000000a",
    #     :aws_instance_id    => "i-12345678",
    #     ...
    #     :aws_availability_zone => "us-east-1b"
    #     }]
    #
    #  # wait until instance enters 'operational' state and get it's initial password
    #
    #  puts ec2.get_initial_password(my_awesome_instance[:aws_instance_id], my_awesome_key[:aws_material]) #=> "MhjWcgZuY6"
    #
    def get_initial_password(instance_id, private_key)
      console_output   = get_console_output(instance_id)
      crypted_password = console_output[:aws_output][%r{<Password>(.+)</Password>}m] && $1
      unless crypted_password
        raise AwsError.new("Initial password was not found in console output for #{instance_id}")
      else
        OpenSSL::PKey::RSA.new(private_key).private_decrypt(Base64.decode64(crypted_password))
      end
    rescue Exception
      on_exception
    end

    # Bundle a Windows image.
    # Internally, it queues the bundling task and shuts down the instance.
    # It then takes a snapshot of the Windows volume bundles it, and uploads it to
    # S3. After bundling completes, Aws::Ec2#register_image may be used to
    # register the new Windows AMI for subsequent launches.
    #
    #   ec2.bundle_instance('i-e3e24e8a', 'my-awesome-bucket', 'my-win-image-1') #=>
    #    [{:aws_update_time => "2008-10-16T13:58:25.000Z",
    #      :s3_bucket       => "kd-win-1",
    #      :s3_prefix       => "win2pr",
    #      :aws_state       => "pending",
    #      :aws_id          => "bun-26a7424f",
    #      :aws_instance_id => "i-878a25ee",
    #      :aws_start_time  => "2008-10-16T13:58:02.000Z"}]
    #
    def bundle_instance(instance_id, s3_bucket, s3_prefix,
        s3_owner_aws_access_key_id=nil, s3_owner_aws_secret_access_key=nil,
        s3_expires = S3Interface::DEFAULT_EXPIRES_AFTER,
        s3_upload_policy='ec2-bundle-read')
      # S3 access and signatures
      s3_owner_aws_access_key_id     ||= @aws_access_key_id
      s3_owner_aws_secret_access_key ||= @aws_secret_access_key
      s3_expires = Time.now.utc + s3_expires if s3_expires.is_a?(Fixnum) && (s3_expires < S3Interface::ONE_YEAR_IN_SECONDS)
      # policy
      policy          = {'expiration' => s3_expires.strftime('%Y-%m-%dT%H:%M:%SZ'),
                         'conditions' => [{'bucket' => s3_bucket},
                                          {'acl' => s3_upload_policy},
                                          ['starts-with', '$key', s3_prefix]]}.to_json
      policy64        = Base64.encode64(policy).gsub("\n", "")
      signed_policy64 = Utils.sign(s3_owner_aws_secret_access_key, policy64)
      # fill request params
      params          = {'InstanceId'                       => instance_id,
                         'Storage.S3.AWSAccessKeyId'        => s3_owner_aws_access_key_id,
                         'Storage.S3.UploadPolicy'          => policy64,
                         'Storage.S3.UploadPolicySignature' => signed_policy64,
                         'Storage.S3.Bucket'                => s3_bucket,
                         'Storage.S3.Prefix'                => s3_prefix,
      }
      link            = generate_request("BundleInstance", params)
      request_info(link, QEc2BundleInstanceParser.new)
    rescue Exception
      on_exception
    end

    # Describe the status of the Windows AMI bundlings.
    # If +list+ is omitted the returns the whole list of tasks.
    #
    #  ec2.describe_bundle_tasks(['bun-4fa74226']) #=>
    #    [{:s3_bucket         => "my-awesome-bucket"
    #      :aws_id            => "bun-0fa70206",
    #      :s3_prefix         => "win1pr",
    #      :aws_start_time    => "2008-10-14T16:27:57.000Z",
    #      :aws_update_time   => "2008-10-14T16:37:10.000Z",
    #      :aws_error_code    => "Client.S3Error",
    #      :aws_error_message =>
    #       "AccessDenied(403)- Invalid according to Policy: Policy Condition failed: [\"eq\", \"$acl\", \"aws-exec-read\"]",
    #      :aws_state         => "failed",
    #      :aws_instance_id   => "i-e3e24e8a"}]
    #
    def describe_bundle_tasks(list=[])
      link = generate_request("DescribeBundleTasks", hash_params('BundleId', list.to_a))
      request_info(link, QEc2DescribeBundleTasksParser.new)
    rescue Exception
      on_exception
    end

    # Cancel an in‐progress or pending bundle task by id.
    #
    #  ec2.cancel_bundle_task('bun-73a7421a') #=>
    #   [{:s3_bucket         => "my-awesome-bucket"
    #     :aws_id            => "bun-0fa70206",
    #     :s3_prefix         => "win02",
    #     :aws_start_time    => "2008-10-14T13:00:29.000Z",
    #     :aws_error_message => "User has requested bundling operation cancellation",
    #     :aws_state         => "failed",
    #     :aws_update_time   => "2008-10-14T13:01:31.000Z",
    #     :aws_error_code    => "Client.Cancelled",
    #     :aws_instance_id   => "i-e3e24e8a"}
    #
    def cancel_bundle_task(bundle_id)
      link = generate_request("CancelBundleTask", {'BundleId' => bundle_id})
      request_info(link, QEc2BundleInstanceParser.new)
    rescue Exception
      on_exception
    end

    #-----------------------------------------------------------------
    #      Security groups
    #-----------------------------------------------------------------

    # Retrieve Security Group information. If +list+ is omitted the returns the whole list of groups.
    #
    #  ec2.describe_security_groups #=>
    #    [{:aws_group_name  => "default-1",
    #      :aws_owner       => "000000000888",
    #      :aws_description => "a default security group",
    #      :aws_perms       =>
    #        [ {:protocol => "tcp", :from_port=>"1000", :to_port=>"2000",
    #           :ip_ranges=>[{cidr_ip=>"10.1.2.3/32"}, {cidr_ip=>"192.168.1.10/24"}],
    #           :groups =>  [{:owner=>"123456789012", :group_name="default"}] },
    #
    #          {:protocol ="icmp", :from_port="-1", :to_port=>"-1",
    #           :ip_ranges=>[{:cidr_ip=>"0.0.0.0/0"}],
    #           :groups=>[] },
    #
    #          {:protocol=>"udp", :from_port=>"0", :to_port=>"65535",
    #           :ip_ranges=>[],
    #           :groups=>[{:owner=>"123456789012", :group_name=>"newgroup"}, {:owner=>"123456789012", :group_name=>"default"}],
    #
    #          {:protocol=>"tcp", :from_port="22", :to_port=>"22",
    #           :ip_ranges=>[{:cidr_ip=>"0.0.0.0/0"}],
    #           :groups=>[{:owner=>"", :group_name=>"default"}] },
    #
    #         ..., {...}
    #        ]
    #
    def describe_security_groups(list=[])
      link = generate_request("DescribeSecurityGroups", hash_params('GroupName', list.to_a))
      request_cache_or_info(:describe_security_groups, link, QEc2DescribeSecurityGroupsParser, @@bench, list.nil? || list.empty?) do |parser|
      result = []
      parser.result.each do |item|
        perms = []
        item.ipPermissions.each do |perm|
          current = {:from_port => perm.fromPort,
                     :to_port => perm.toPort,
                     :protocol => perm.ipProtocol,
                     :groups => [], :ip_ranges => []}
          perm.groups.each do |ngroup|
             current[:groups] << {:group_name => ngroup.groupName, :owner => ngroup.userId}
          end
          perm.ipRanges.each do |cidr_ip|
             current[:ip_ranges] << {:cidr_ip => cidr_ip.cidrIp}
          end
        perms << current
        end
        result << {:aws_owner       => item.ownerId,
                   :aws_group_name  => item.groupName,
                   :aws_description => item.groupDescription,
                   :aws_perms       => perms}
        end
        result
      end
    rescue Exception
      on_exception
    end

    # Create new Security Group. Returns +true+ or an exception.
    #
    #  ec2.create_security_group('default-1',"Default allowing SSH, HTTP, and HTTPS ingress") #=> true
    #
    def create_security_group(name, description)
      # EC2 doesn't like an empty description...
      description = " " if Aws::Utils.blank?(description)
      link = generate_request("CreateSecurityGroup",
                              'GroupName'        => name.to_s,
                              'GroupDescription' => description.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Remove Security Group. Returns +true+ or an exception.
    #
    #  ec2.delete_security_group('default-1') #=> true
    #
    def delete_security_group(name)
      link = generate_request("DeleteSecurityGroup",
                              'GroupName' => name.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Authorize OR Revoke ingress for security group, depending on the value of the 'action' parameter.
    # If you 'authorize' then you allow instances that are member of some other
    # security groups, or some range of ip addresses to open connections to instances in
    # my group. Can specify an array of ip addresses, source groups or mix of both in a single rule:
    #
    # ec2.manage_security_group_ingress('authorize', 'new_firewall', 80, 80, 'tcp', ['192.168.0.1/32', '10.0.0.1/24'],
    #             [{'group_name'=>'default', 'owner'=>'297467797945'}, {'group_name'=>'test', 'owner'=>'123456789012'}])
    #
    # ec2.manage_security_group_ingress('new_firewall', 0, 1000, 'udp', 'revoke', [],
    #                             [{'group_name'=>'default', 'owner'=>'123456789012'}])
    #
    # ec2.manage_security_group_ingress('new_firewall', 0, 1000, 'udp', 'authorize', ['0.0.0.0/0'])
    #
    # Similarly, if you specify 'revoke' as the action parameter then you will remove the specified
    # source ip addresses or source groups from access to instances in the named group:
    #
    def manage_security_group_ingress(name, from_port, to_port, protocol, action, source_ip_ranges, source_groups = [])
      call_params = {  'GroupName'   => name.to_s,
                      'IpPermissions.1.IpProtocol' => protocol.to_s,
                       'IpPermissions.1.FromPort'   => from_port.to_s,
                       'IpPermissions.1.ToPort'     => to_port.to_s  }
      source_ip_ranges.each_index do |i|
        call_params.merge!({"IpPermissions.1.IpRanges.#{i+1}.CidrIp" => source_ip_ranges[i].to_s})
      end
      source_groups.each_index do |i|
        call_params.merge!({"IpPermissions.1.Groups.#{i+1}.GroupName" => source_groups[i]['group_name'].to_s,
                            "IpPermissions.1.Groups.#{i+1}.UserId"=> source_groups[i]['owner'].to_s.gsub(/-/,'')})
      end
      unless ['Authorize', 'Revoke'].include?(action.capitalize)
         raise AwsError.new("Invalid action #{action} - must be one of \'Authorize\' or \'Revoke\'")
      end
      link = generate_request("#{action.capitalize}SecurityGroupIngress", call_params)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
      rescue Exception
        on_exception
    end

    # Authorize named ingress for security group. Allows instances that are member of someone
    # else's security group to open connections to instances in my group.
    #
    #  ec2.authorize_security_group_named_ingress('my_awesome_group', '7011-0219-8268', 'their_group_name') #=> true
    #
    def authorize_security_group_named_ingress(name, owner, group)
      link = generate_request("AuthorizeSecurityGroupIngress",
                              'GroupName'                  => name.to_s,
                              'SourceSecurityGroupName'    => group.to_s,
                              'SourceSecurityGroupOwnerId' => owner.to_s.gsub(/-/, ''))
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Revoke named ingress for security group.
    #
    #  ec2.revoke_security_group_named_ingress('my_awesome_group', aws_user_id, 'another_group_name') #=> true
    #
    def revoke_security_group_named_ingress(name, owner, group)
      link = generate_request("RevokeSecurityGroupIngress",
                              'GroupName'                  => name.to_s,
                              'SourceSecurityGroupName'    => group.to_s,
                              'SourceSecurityGroupOwnerId' => owner.to_s.gsub(/-/, ''))
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Add permission to a security group. Returns +true+ or an exception. +protocol+ is one of :'tcp'|'udp'|'icmp'.
    #
    #  ec2.authorize_security_group_IP_ingress('my_awesome_group', 80, 82, 'udp', '192.168.1.0/8') #=> true
    #  ec2.authorize_security_group_IP_ingress('my_awesome_group', -1, -1, 'icmp') #=> true
    #
    def authorize_security_group_IP_ingress(name, from_port, to_port, protocol='tcp', cidr_ip='0.0.0.0/0')
      link = generate_request("AuthorizeSecurityGroupIngress",
                              'GroupName'  => name.to_s,
                              'IpProtocol' => protocol.to_s,
                              'FromPort'   => from_port.to_s,
                              'ToPort'     => to_port.to_s,
                              'CidrIp'     => cidr_ip.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Remove permission from a security group. Returns +true+ or an exception. +protocol+ is one of :'tcp'|'udp'|'icmp' ('tcp' is default).
    #
    #  ec2.revoke_security_group_IP_ingress('my_awesome_group', 80, 82, 'udp', '192.168.1.0/8') #=> true
    #
    def revoke_security_group_IP_ingress(name, from_port, to_port, protocol='tcp', cidr_ip='0.0.0.0/0')
      link = generate_request("RevokeSecurityGroupIngress",
                              'GroupName'  => name.to_s,
                              'IpProtocol' => protocol.to_s,
                              'FromPort'   => from_port.to_s,
                              'ToPort'     => to_port.to_s,
                              'CidrIp'     => cidr_ip.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    #-----------------------------------------------------------------
    #      Keys
    #-----------------------------------------------------------------

    # Retrieve a list of SSH keys. Returns an array of keys or an exception. Each key is
    # represented as a two-element hash.
    #
    #  ec2.describe_key_pairs #=>
    #    [{:aws_fingerprint=> "01:02:03:f4:25:e6:97:e8:9b:02:1a:26:32:4e:58:6b:7a:8c:9f:03", :aws_key_name=>"key-1"},
    #     {:aws_fingerprint=> "1e:29:30:47:58:6d:7b:8c:9f:08:11:20:3c:44:52:69:74:80:97:08", :aws_key_name=>"key-2"},
    #      ..., {...} ]
    #
    def describe_key_pairs(list=[])
      link = generate_request("DescribeKeyPairs", hash_params('KeyName', list.to_a))
      request_cache_or_info :describe_key_pairs, link, QEc2DescribeKeyPairParser, @@bench, list.nil? || list.empty?
    rescue Exception
      on_exception
    end

    # Create new SSH key. Returns a hash of the key's data or an exception.
    #
    #  ec2.create_key_pair('my_awesome_key') #=>
    #    {:aws_key_name    => "my_awesome_key",
    #     :aws_fingerprint => "01:02:03:f4:25:e6:97:e8:9b:02:1a:26:32:4e:58:6b:7a:8c:9f:03",
    #     :aws_material    => "-----BEGIN RSA PRIVATE KEY-----\nMIIEpQIBAAK...Q8MDrCbuQ=\n-----END RSA PRIVATE KEY-----"}
    #
    def create_key_pair(name)
      link = generate_request("CreateKeyPair",
                              'KeyName' => name.to_s)
      request_info(link, QEc2CreateKeyPairParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Import existing SSH key. Returns a hash of the key's data or an exception.
    #
    #  ec2.import_key_pair('my_awesome_key',
    #                      'ssh-rsa AABB3NzaC1yc2FSAAADAQABAAABAQCntvz2Cpx8EE4lBRjQKOtwNaGeJXjgnFLaxnQH4HB+dRTinjlew+153KLCjAMbbanD9Wym/b1FfSHywP299RdTPpBZ2QD7Hh7qKp8penGszFQbaSewYQTBP9Htjn7NDg3VeVcIx0LP3lmp4ZNnYDZGLKCGJJ+ldT/cljW3FAA2/xwco98BujLlKUcU/BZlZ4zvESM3S0gF3pgOjuz2UKAEbsbuuaEQP88NZ/GXXIUgGNFoJSpxDrNCHA7pap/3gdyPq3zTkt4YK/bSxSJ24FMfYtehB36V9rqV8RsIro+yrzRBW4XcA976OKQbh5pS75rp herp@derp')
    #  #=>
    #    {:aws_key_name    => "my_awesome_key",
    #     :aws_fingerprint => "01:02:03:f4:25:e6:97:e8:9b:02:1a:26:32:4e:58:6b:7a:8c:9f:03"}
    #
    def import_key_pair(name, public_key)
      link = generate_request("ImportKeyPair",
                              "KeyName" => name.to_s,
                              "PublicKeyMaterial"=>Base64.encode64(public_key.to_s))
      request_info(link, QEc2ImportPublicKeyParser.new(:logger => @logger))
      rescue Exception
        on_exception
    end

    # Delete a key pair. Returns +true+ or an exception.
    #
    #  ec2.delete_key_pair('my_awesome_key') #=> true
    #
    def delete_key_pair(name)
      link = generate_request("DeleteKeyPair",
                              'KeyName' => name.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    #-----------------------------------------------------------------
    #      Elastic IPs
    #-----------------------------------------------------------------

    # Acquire a new elastic IP address for use with your account.
    # Returns allocated IP address or an exception.
    #
    #  ec2.allocate_address #=> '75.101.154.140'
    #
    def allocate_address
      link = generate_request("AllocateAddress")
      request_info(link, QEc2AllocateAddressParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Associate an elastic IP address with an instance.
    # Returns +true+ or an exception.
    #
    #  ec2.associate_address('i-d630cbbf', '75.101.154.140') #=> true
    #
    def associate_address(instance_id, public_ip)
      link = generate_request("AssociateAddress",
                              "InstanceId" => instance_id.to_s,
                              "PublicIp"   => public_ip.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # List elastic IP addresses assigned to your account.
    # Returns an array of 2 keys (:instance_id and :public_ip) hashes:
    #
    #  ec2.describe_addresses  #=> [{:instance_id=>"i-d630cbbf", :public_ip=>"75.101.154.140"},
    #                               {:instance_id=>nil, :public_ip=>"75.101.154.141"}]
    #
    #  ec2.describe_addresses('75.101.154.140') #=> [{:instance_id=>"i-d630cbbf", :public_ip=>"75.101.154.140"}]
    #
    def describe_addresses(list=[])
      link = generate_request("DescribeAddresses",
                              hash_params('PublicIp', list.to_a))
      request_cache_or_info :describe_addresses, link, QEc2DescribeAddressesParser, @@bench, list.nil? || list.empty?
    rescue Exception
      on_exception
    end

    # Disassociate the specified elastic IP address from the instance to which it is assigned.
    # Returns +true+ or an exception.
    #
    #  ec2.disassociate_address('75.101.154.140') #=> true
    #
    def disassociate_address(public_ip)
      link = generate_request("DisassociateAddress",
                              "PublicIp" => public_ip.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Release an elastic IP address associated with your account.
    # Returns +true+ or an exception.
    #
    #  ec2.release_address('75.101.154.140') #=> true
    #
    def release_address(public_ip)
      link = generate_request("ReleaseAddress",
                              "PublicIp" => public_ip.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    #-----------------------------------------------------------------
    #      Availability zones
    #-----------------------------------------------------------------

    # Describes availability zones that are currently available to the account and their states.
    # Returns an array of 2 keys (:zone_name and :zone_state) hashes:
    #
    #  ec2.describe_availability_zones  #=> [{:region_name=>"us-east-1",
    #                                         :zone_name=>"us-east-1a",
    #                                         :zone_state=>"available"}, ... ]
    #
    #  ec2.describe_availability_zones('us-east-1c') #=> [{:region_name=>"us-east-1",
    #                                                      :zone_state=>"available",
    #                                                      :zone_name=>"us-east-1c"}]
    #
    def describe_availability_zones(list=[])
      link = generate_request("DescribeAvailabilityZones",
                              hash_params('ZoneName', list.to_a))
      request_cache_or_info :describe_availability_zones, link, QEc2DescribeAvailabilityZonesParser, @@bench, list.nil? || list.empty?
    rescue Exception
      on_exception
    end

# This is using the new way, but not sure it's backwrads compatible
    def describe_availability_zones2(options={})
      link = generate_request("DescribeAvailabilityZones", options={})
      request_info_xml_simple(self.class.connection_name, @params, link, @logger,
                              :group_tags     =>{"DBInstances"      =>"DBInstance",
                                                 "DBParameterGroups"=>"DBParameterGroup",
                                                 "DBSecurityGroups" =>"DBSecurityGroup",
                                                 "EC2SecurityGroups"=>"EC2SecurityGroup",
                                                 "IPRanges"         =>"IPRange"},
                              :force_array    =>["DBInstances",
                                                 "DBParameterGroups",
                                                 "DBSecurityGroups",
                                                 "EC2SecurityGroups",
                                                 "IPRanges"],
                              :pull_out_array =>options[:pull_out_array],
                              :pull_out_single=>options[:pull_out_single],
                              :wrapper        =>options[:wrapper])
    rescue Exception
      on_exception
    end


    #-----------------------------------------------------------------
    #      Regions
    #-----------------------------------------------------------------

    # Describe regions.
    #
    #  ec2.describe_regions  #=> ["eu-west-1", "us-east-1"]
    #
    def describe_regions(list=[])
      link = generate_request("DescribeRegions",
                              hash_params('RegionName', list.to_a))
      request_cache_or_info :describe_regions, link, QEc2DescribeRegionsParser, @@bench, list.nil? || list.empty?
    rescue Exception
      on_exception
    end


    #-----------------------------------------------------------------
    #      EBS: Volumes
    #-----------------------------------------------------------------

    # Describe all EBS volumes.
    #
    #  ec2.describe_volumes #=>
    #      [{:aws_size              => 94,
    #        :aws_device            => "/dev/sdc",
    #        :aws_attachment_status => "attached",
    #        :zone                  => "merlot",
    #        :snapshot_id           => nil,
    #        :aws_attached_at       => Wed Jun 18 08:19:28 UTC 2008,
    #        :aws_status            => "in-use",
    #        :aws_id                => "vol-60957009",
    #        :aws_created_at        => Wed Jun 18 08:19:20s UTC 2008,
    #        :aws_instance_id       => "i-c014c0a9"},
    #       {:aws_size       => 1,
    #        :zone           => "merlot",
    #        :snapshot_id    => nil,
    #        :aws_status     => "available",
    #        :aws_id         => "vol-58957031",
    #        :aws_created_at => Wed Jun 18 08:19:21 UTC 2008,}, ... ]
    #
    def describe_volumes(list=[])
      link = generate_request("DescribeVolumes",
                              hash_params('VolumeId', list.to_a))
      request_cache_or_info :describe_volumes, link, QEc2DescribeVolumesParser, @@bench, list.nil? || list.empty?
    rescue Exception
      on_exception
    end

    # Create new EBS volume based on previously created snapshot.
    # +Size+ in Gigabytes.
    #
    #  ec2.create_volume('snap-000000', 10, zone) #=>
    #      {:snapshot_id    => "snap-e21df98b",
    #       :aws_status     => "creating",
    #       :aws_id         => "vol-fc9f7a95",
    #       :zone           => "merlot",
    #       :aws_created_at => Tue Jun 24 18:13:32 UTC 2008,
    #       :aws_size       => 94}
    #
    def create_volume(snapshot_id, size, zone)
      params = {'Size' => size.to_s, 'AvailabilityZone' => zone.to_s}
      params['SnapshotId'] = snapshot_id if snapshot_id && snapshot_id.length > 0 # snapshotId is conditional
      link = generate_request("CreateVolume",
                              params)
      request_info(link, QEc2CreateVolumeParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Delete the specified EBS volume.
    # This does not deletes any snapshots created from this volume.
    #
    #  ec2.delete_volume('vol-b48a6fdd') #=> true
    #
    def delete_volume(volume_id)
      link = generate_request("DeleteVolume",
                              "VolumeId" => volume_id.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Creates an Amazon EBS-backed AMI from an Amazon EBS-backed instance
    # Instance must be either the running or stopped state
    #
    # ec2.create_image('i-4jhdmaw', 'New image')
    #
    def create_image(instance_id, name, description="")
      link = generate_request("CreateImage",
                              "InstanceId" => instance_id,
                              "Name" => name,
                              "Description" => description)
      request_info(link, QEc2CreateImageParser.new(:logger => @logger))
    rescue
        on_exception
    end

    # Attach the specified EBS volume to a specified instance, exposing the
    # volume using the specified device name.
    #
    #  ec2.attach_volume('vol-898a6fe0', 'i-7c905415', '/dev/sdh') #=>
    #    { :aws_instance_id => "i-7c905415",
    #      :aws_device      => "/dev/sdh",
    #      :aws_status      => "attaching",
    #      :aws_attached_at => "2008-03-28T14:14:39.000Z",
    #      :aws_id          => "vol-898a6fe0" }
    #
    def attach_volume(volume_id, instance_id, device)
      link = generate_request("AttachVolume",
                              "VolumeId"   => volume_id.to_s,
                              "InstanceId" => instance_id.to_s,
                              "Device"     => device.to_s)
      request_info(link, QEc2AttachAndDetachVolumeParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Detach the specified EBS volume from the instance to which it is attached.
    #
    #   ec2.detach_volume('vol-898a6fe0') #=>
    #     { :aws_instance_id => "i-7c905415",
    #       :aws_device      => "/dev/sdh",
    #       :aws_status      => "detaching",
    #       :aws_attached_at => "2008-03-28T14:38:34.000Z",
    #       :aws_id          => "vol-898a6fe0"}
    #
    def detach_volume(volume_id, instance_id=nil, device=nil, force=nil)
      hash = {"VolumeId" => volume_id.to_s}
      hash["InstanceId"] = instance_id.to_s unless Aws::Utils.blank?(instance_id)
      hash["Device"] = device.to_s unless Aws::Utils.blank?(device)
      hash["Force"] = 'true' if     force
      #
      link = generate_request("DetachVolume", hash)
      request_info(link, QEc2AttachAndDetachVolumeParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end


    #-----------------------------------------------------------------
    #      EBS: Snapshots
    #-----------------------------------------------------------------

    # Describe all EBS snapshots.
    #
    # ec2.describe_snapshots #=>
    #   [ { :aws_progress   => "100%",
    #       :aws_status     => "completed",
    #       :aws_id         => "snap-72a5401b",
    #       :aws_volume_id  => "vol-5582673c",
    #       :aws_started_at => "2008-02-23T02:50:48.000Z"},
    #     { :aws_progress   => "100%",
    #       :aws_status     => "completed",
    #       :aws_id         => "snap-75a5401c",
    #       :aws_volume_id  => "vol-5582673c",
    #       :aws_started_at => "2008-02-23T16:23:19.000Z" },...]
    #
    def describe_snapshots(list=[])
      link = generate_request("DescribeSnapshots",
                              hash_params('SnapshotId', list.to_a))
      request_cache_or_info :describe_snapshots, link, QEc2DescribeSnapshotsParser, @@bench, list.nil? || list.empty?
    rescue Exception
      on_exception
    end

    def describe_owned_snapshots(list=[])
      params = {"Owner" => "self"}
      snap_ids = hash_params('SnapshotId', list.to_a)
      params.update(snap_ids)
      link = generate_request("DescribeSnapshots",
                              params)
      request_cache_or_info :describe_owned_snapshots, link, QEc2DescribeSnapshotsParser, @@bench, list.nil? || list.empty?
    rescue Exception
      on_exception
    end


    # Create a snapshot of specified volume.
    #
    #  ec2.create_snapshot('vol-898a6fe0') #=>
    #      {:aws_volume_id  => "vol-fd9f7a94",
    #       :aws_started_at => Tue Jun 24 18:40:40 UTC 2008,
    #       :aws_progress   => "",
    #       :aws_status     => "pending",
    #       :aws_id         => "snap-d56783bc"}
    #
    def create_snapshot(volume_id, options={})
      link = generate_request("CreateSnapshot", options.merge({"VolumeId" => volume_id.to_s}))
      request_info(link, QEc2CreateSnapshotParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Create a snapshot of specified volume, but with the normal retry algorithms disabled.
    # This method will return immediately upon error.  The user can specify connect and read timeouts (in s)
    # for the connection to AWS.  If the user does not specify timeouts, try_create_snapshot uses the default values
    # in Rightscale::HttpConnection.
    #
    #  ec2.try_create_snapshot('vol-898a6fe0') #=>
    #      {:aws_volume_id  => "vol-fd9f7a94",
    #       :aws_started_at => Tue Jun 24 18:40:40 UTC 2008,
    #       :aws_progress   => "",
    #       :aws_status     => "pending",
    #       :aws_id         => "snap-d56783bc"}
    #
    def try_create_snapshot(volume_id, connect_timeout = nil, read_timeout = nil)
      # For safety in the ensure block...we don't want to restore values
      # if we never read them in the first place
      orig_reiteration_time                         = nil
      orig_http_params                              = nil

      orig_reiteration_time                         = Aws::AWSErrorHandler::reiteration_time
      Aws::AWSErrorHandler::reiteration_time        = 0

      orig_http_params                              = Rightscale::HttpConnection::params()
      new_http_params                               = orig_http_params.dup
      new_http_params[:http_connection_retry_count] = 0
      new_http_params[:http_connection_open_timeout] = connect_timeout if !connect_timeout.nil?
      new_http_params[:http_connection_read_timeout] = read_timeout if !read_timeout.nil?
      Rightscale::HttpConnection::params = new_http_params

      link                               = generate_request("CreateSnapshot",
                                                            "VolumeId" => volume_id.to_s)
      request_info(link, QEc2CreateSnapshotParser.new(:logger => @logger))

    rescue Exception
      on_exception
    ensure
      Aws::AWSErrorHandler::reiteration_time = orig_reiteration_time if orig_reiteration_time
      Rightscale::HttpConnection::params = orig_http_params if orig_http_params
    end

    # Delete the specified snapshot.
    #
    #  ec2.delete_snapshot('snap-55a5403c') #=> true
    #
    def delete_snapshot(snapshot_id)
      link = generate_request("DeleteSnapshot",
                              "SnapshotId" => snapshot_id.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Add/replace one tag to a resource
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/index.html?ApiReference_query_CreateTags.html
    #
    #  ec2.create_tag('ami-1a2b3c4d', 'webserver') #=> true
    #  ec2.create_tag('i-7f4d3a2b',   'stack', 'Production') #=> true
    #
    def create_tag(resource_id, key, value = nil)
      link = generate_request("CreateTags",
                              "ResourceId.1" => resource_id.to_s,
                              "Tag.1.Key"    => key.to_s,
                              "Tag.1.Value"  => value.to_s)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Describe tags
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/index.html?ApiReference_query_DescribeTags.html
    #
    #  ec2.describe_tags
    #  ec2.describe_tags(
    #    'Filter.1.Name' => 'resource-type', 'Filter.1.Value.1' => 'instance',
    #    'Filter.2.Name' => 'value',         'Filter.2.Value.1' => 'Test', 'Filter.2.Value.2' => 'Production'
    #  )
    #
    def describe_tags(filters = {})
      link = generate_request("DescribeTags", filters)
      request_info(link, QEc2DescribeTagsParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Delete one or all tags from a resource
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/index.html?ApiReference_query_DeleteTags.html
    #
    #  ec2.delete_tag('i-7f4d3a2b', 'stack') #=> true
    #  ec2.delete_tag('i-7f4d3a2b', 'stack', 'Production') #=> true
    #
    # "If you omit Tag.n.Value, we delete the tag regardless of its value. If
    # you specify this parameter with an empty string as the value, we delete the
    # key only if its value is an empty string."
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/ApiReference_query_DeleteTags.html
    #
    def delete_tag(resource_id, key, value = nil)
      request_args = {"ResourceId.1" => resource_id.to_s, "Tag.1.Key" => key.to_s}
      request_args["Tag.1.Value"] = value.to_s if value

      link = generate_request("DeleteTags", request_args)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    #-----------------------------------------------------------------
    #      VPC related
    #-----------------------------------------------------------------

    # Create VPC
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/ApiReference-query-CreateVpc.html
    #
    # ec2.create_vpc("10.0.0.0/16")
    # FIXME: EVen though the EC2 docs describe the parameter instanceTenancy,
    # I could not get it to recognize that
    def create_vpc(cidr_block = "10.0.0.0/16")
      params = { "CidrBlock" => cidr_block }
      link = generate_request("CreateVpc", params)
      request_info(link, QEc2VpcsParser.new("vpc", :logger => @logger))
    rescue Exception
      on_exception
    end


    # Describe  VPC's
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/ApiReference-query-DescribeVpcs.html
    #
    # ec2.describe_vpcs
    # ec2.describe_vpcs(vpcId1, vpcId2, 'Filter.1.Name' => 'state', 'Filter.1.Value' = > 'pending', ...)
    def describe_vpcs(*args)
      if args.last.is_a?(Hash)
        params = args.pop.dup
      else
        params = {}
      end
      1.upto(args.size) { |i| params["VpcId.#{i}"] = args[i-1] }
      link = generate_request("DescribeVpcs", params)
      request_info(link, QEc2VpcsParser.new("item", :logger => @logger))
    rescue Exception
      on_exception
    end

    # Delete VPC
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/ApiReference-query-DeleteVpc.html
    #
    # ec2.delete_vpc(vpc_id)
    def delete_vpc(vpc_id)
      params = { "VpcId" => vpc_id }
      link = generate_request("DeleteVpc", params)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Describe network interfaces in a VPC
    # http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-DescribeNetworkInterfaces.html
    #
    # ec2.describe_network_interfaces
    # ec2.describe_network_interfaces(ifaceId1, ifaceId2, ...,
    #                                 'Filter.1.Name' => 'addresses.primary',
    #                                 'Filter.1.Value.1' => true,
    #                                 'Filter.2.Name' => ...)
    def describe_network_interfaces(*args)
      if args.last.is_a?(Hash)
        filters = args.pop.dup
      else
        filters = {}
      end
      ids = hash_params('NetworkInterfaceId', args)
      params = filters.merge(ids)
      params['Version'] = "2013-02-01"
      link = generate_request('DescribeNetworkInterfaces', params)
      request_info(link, QEc2NetworkInterfacesParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Create a new network interface in a VPC
    # http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-CreateNetworkInterface.html
    #
    # ec2.create_network_interface("subnet-a61dafcf")
    def create_network_interface(subnet_id, *args)
      if args.last.is_a?(Hash)
        params = args.pop.dup
      else
        params = {}
      end
      params.merge!({'SubnetId' => subnet_id, 'Version' => "2013-02-01"})
      link = generate_request('CreateNetworkInterface', params)
      request_info(link, QEc2NetworkInterfacesParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Attach a network interface to an instance
    # http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-AttachNetworkInterface.html
    #
    # ec2.attach_network_interface("eni-ffda3197", "i-9cc316fe", 1)
    def attach_network_interface(network_interface_id, instance_id, device_index)
      params = {
        "NetworkInterfaceId" => network_interface_id,
        "InstanceId" => instance_id,
        "DeviceIndex" => device_index,
        "Version" => "2013-02-01",
      }
      link = generate_request('AttachNetworkInterface', params)
      request_info(link, QEc2AttachNetworkInterfaceParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Detach a network interface from an instance
    # http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-DetachNetworkInterface.html
    #
    # ec2.detach_network_interface("eni-attach-d94b09b0")
    # ec2.detach_network_interface("eni-attach-d94b09b0", true)
    def detach_network_interface(attachment_id, force=false)
      params = {
        "AttachmentId" => attachment_id,
        "Force" => force,
        "Version" => "2013-02-01",
      }
      link = generate_request('DetachNetworkInterface', params)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Delete a network interface from a VPC
    # http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-DeleteNetworkInterface.html
    #
    # ec2.delete_network_interface("eni-ffda3197")
    def delete_network_interface(network_interface_id)
      params = {
        "NetworkInterfaceId" => network_interface_id,
        "Version" => "2013-02-01",
      }
      link = generate_request('DeleteNetworkInterface', params)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    # Create subnet in a VPC
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/ApiReference-query-CreateSubnet.html
    #
    # ec2.create_subnet(vpc_id, cidr_block)
    # ec2.create_subnet(vpc_id, cidr_block, availability_zone))
    def create_subnet(vpc_id, cidr_block, availability_zone = nil)
      params = { "VpcId" => vpc_id, "CidrBlock" => cidr_block }
      params["AvailabilityZone"] = availability_zone if availability_zone
      link = generate_request("CreateSubnet", params)
      request_info(link, QEc2SubnetsParser.new("subnet", :logger => @logger))
    rescue Exception
      on_exception
    end

    # Describe subnets
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/ApiReference-query-DescribeSubnets.html
    #
    # ec2.describe_subnets
    # ecs.describe_subnets(subnetId1, SubnetId2, ...,
    #                      'Filter.1.Name' => 'state',
    #                      'Filter.1.Value.1' => 'pending',
    #                      'Filter.2.Name' => ...)
    def describe_subnets(*args)
      if args.last.is_a?(Hash)
        params = args.pop.dup
      else
        params = {}
      end
      1.upto(args.size) { |i| params["SubnetId.#{i}"] = args[i-1] }
      link = generate_request("DescribeSubnets", params)
      request_info(link, QEc2SubnetsParser.new("item", :logger => @logger))
    rescue Exception
      on_exception
    end

    # Delete Subnet
    # http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/ApiReference-query-DeleteSubnet.html
    #
    # ec2.delete_subnet(subnet_id)
    def delete_subnet(subnet_id)
      params = { "SubnetId" => subnet_id }
      link = generate_request("DeleteSubnet", params)
      request_info(link, RightBoolResponseParser.new(:logger => @logger))
    rescue Exception
      on_exception
    end

    #-----------------------------------------------------------------
    #      PARSERS: Boolean Response Parser
    #-----------------------------------------------------------------

    class RightBoolResponseParser < AwsParser #:nodoc:
      def tagend(name)
        @result = @text=='true' ? true : false if name == 'return'
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: Key Pair
    #-----------------------------------------------------------------

    class QEc2DescribeKeyPairParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @item = {} if name == 'item'
      end

      def tagend(name)
        case name
          when 'keyName' then
            @item[:aws_key_name] = @text
          when 'keyFingerprint' then
            @item[:aws_fingerprint] = @text
          when 'item' then
            @result << @item
        end
      end

      def reset
        @result = [];
      end
    end

    class QEc2CreateKeyPairParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @result = {} if name == 'CreateKeyPairResponse'
      end

      def tagend(name)
        case name
          when 'keyName' then
            @result[:aws_key_name] = @text
          when 'keyFingerprint' then
            @result[:aws_fingerprint] = @text
          when 'keyMaterial' then
            @result[:aws_material] = @text
        end
      end
    end

    class QEc2ImportPublicKeyParser < QEc2CreateKeyPairParser #:nodoc:
      def tagstart(name, attributes)
        @result = {} if name == 'ImportKeyPairResponse'
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: Security Groups
    #-----------------------------------------------------------------

    class QEc2UserIdGroupPairType #:nodoc:
      attr_accessor :userId
      attr_accessor :groupName
    end

    class QEc2IpRangeItemType #:nodoc:
      attr_accessor :cidrIp
    end

    class QEc2IpPermissionType #:nodoc:
      attr_accessor :ipProtocol
      attr_accessor :fromPort
      attr_accessor :toPort
      attr_accessor :groups
      attr_accessor :ipRanges
    end

    class QEc2SecurityGroupItemType #:nodoc:
      attr_accessor :groupName
      attr_accessor :groupDescription
      attr_accessor :ownerId
      attr_accessor :ipPermissions
    end


    class QEc2DescribeSecurityGroupsParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        case name
          when 'item'
            if @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo'
              @group               = QEc2SecurityGroupItemType.new
              @group.ipPermissions = []
            elsif @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo/item/ipPermissions'
              @perm          = QEc2IpPermissionType.new
              @perm.ipRanges = []
              @perm.groups   = []
            elsif @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo/item/ipPermissions/item/groups'
              @sgroup = QEc2UserIdGroupPairType.new
            elsif @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo/item/ipPermissions/item/ipRanges'
              @sIpRange = QEc2IpRangeItemType.new
            end
        end
      end

      def tagend(name)
        case name
          when 'ownerId'          then @group.ownerId   = @text
          when 'groupDescription' then @group.groupDescription = @text
          when 'groupName'
            if @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo/item'
              @group.groupName  = @text
            elsif @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo/item/ipPermissions/item/groups/item'
              @sgroup.groupName = @text
            end
          when 'ipProtocol'       then @perm.ipProtocol = @text
          when 'fromPort'         then @perm.fromPort   = @text
          when 'toPort'           then @perm.toPort     = @text
          when 'userId'           then @sgroup.userId   = @text
          when 'cidrIp'           then @sIpRange.cidrIp = @text
          when 'item'
            if @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo/item/ipPermissions/item/groups'
              @perm.groups << @sgroup
            elsif @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo/item/ipPermissions/item/ipRanges'
              @perm.ipRanges << @sIpRange
            elsif @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo/item/ipPermissions'
              @group.ipPermissions << @perm
            elsif @xmlpath=='DescribeSecurityGroupsResponse/securityGroupInfo'
              @result << @group
            end
        end
      end

      def reset
        @result = []
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: Images
    #-----------------------------------------------------------------

    class QEc2DescribeImagesParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        if name == 'item' && @xmlpath[%r{.*/imagesSet$}]
          @image = {}
        end
      end

      def tagend(name)
        case name
          when 'imageId' then
            @image[:aws_id] = @text
          when 'name' then
            @image[:aws_name] = @text
          when 'description' then
            @image[:aws_description] = @text
          when 'imageLocation' then
            @image[:aws_location] = @text
          when 'imageState' then
            @image[:aws_state] = @text
          when 'imageOwnerId' then
            @image[:aws_owner] = @text
          when 'isPublic' then
            @image[:aws_is_public]= @text == 'true' ? true : false
          when 'productCode' then
            (@image[:aws_product_codes] ||= []) << @text
          when 'architecture' then
            @image[:aws_architecture] = @text
          when 'imageType' then
            @image[:aws_image_type] = @text
          when 'kernelId' then
            @image[:aws_kernel_id] = @text
          when 'ramdiskId' then
            @image[:aws_ramdisk_id] = @text
          when 'rootDeviceType' then
            @image[:aws_root_device_type] = @text
          when 'rootDeviceName' then
            @image[:aws_root_device_name] = @text
          when 'hypervisor' then
            @image[:aws_hypervisor] = @text
          when 'item' then
            @result << @image if @xmlpath[%r{.*/imagesSet$}]
        end
      end

      def reset
        @result = []
      end
    end

    class QEc2RegisterImageParser < AwsParser #:nodoc:
      def tagend(name)
        @result = @text if name == 'imageId'
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: Image Attribute
    #-----------------------------------------------------------------

    class QEc2DescribeImageAttributeParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        case name
          when 'launchPermission'
            @result[:groups] = []
            @result[:users]  = []
          when 'productCodes'
            @result[:aws_product_codes] = []
        end
      end

      def tagend(name)
        # right now only 'launchPermission' is supported by Amazon.
        # But nobody know what will they xml later as attribute. That is why we
        # check for 'group' and 'userId' inside of 'launchPermission/item'
        case name
          when 'imageId' then
            @result[:aws_id] = @text
          when 'group' then
            @result[:groups] << @text if @xmlpath == 'DescribeImageAttributeResponse/launchPermission/item'
          when 'userId' then
            @result[:users] << @text if @xmlpath == 'DescribeImageAttributeResponse/launchPermission/item'
          when 'productCode' then
            @result[:aws_product_codes] << @text
          when 'kernel' then
            @result[:aws_kernel] = @text
          when 'ramdisk' then
            @result[:aws_ramdisk] = @text
          when 'blockDeviceMapping' then
            @result[:block_device_mapping] = @text
        end
      end

      def reset
        @result = {}
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: Instances
    #-----------------------------------------------------------------

    class QEc2DescribeInstancesParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        # DescribeInstances property
        if (name == 'item' && @xmlpath == 'DescribeInstancesResponse/reservationSet') ||
            # RunInstances property
        (name == 'RunInstancesResponse')
          @reservation = {:aws_groups    => [],
                          :instances_set => []}

        elsif (name == 'item') &&
            # DescribeInstances property
        (@xmlpath=='DescribeInstancesResponse/reservationSet/item/instancesSet' ||
            # RunInstances property
        @xmlpath=='RunInstancesResponse/instancesSet')
          # the optional params (sometimes are missing and we dont want them to be nil)
          @instance = {:aws_reason        => '',
                       :dns_name          => '',
                       :private_dns_name  => '',
                       :ami_launch_index  => '',
                       :ssh_key_name      => '',
                       :aws_state         => '',
                       :root_device_type  => '',
                       :root_device_name  => '',
                       :architecture      => '',
                       :subnet_id         => '',
                       :vpc_id            => '',
                       :block_device_mappings => [],
                       :aws_product_codes => [],
                       :tags              => {}}
        end
      end

      def tagend(name)
        case name
          when  'rootDeviceType' then
            @instance[:root_device_type] = @text
          when 'architecture' then
            @instance[:architecture] = @text
          when 'rootDeviceName' then
            @instance[:root_device_name] = @text
          # reservation
          when 'reservationId' then
            @reservation[:aws_reservation_id] = @text
          when 'ownerId' then
            @reservation[:aws_owner] = @text
          when 'groupId' then
            @reservation[:aws_groups] << @text
          # instance
          when 'instanceId' then
            @instance[:aws_instance_id] = @text
          when 'imageId' then
            @instance[:aws_image_id] = @text
          when 'dnsName' then
            @instance[:dns_name] = @text
          when 'privateDnsName' then
            @instance[:private_dns_name] = @text
          when 'reason' then
            @instance[:aws_reason] = @text
          when 'keyName' then
            @instance[:ssh_key_name] = @text
          when 'amiLaunchIndex' then
            @instance[:ami_launch_index] = @text
          when 'code' then
            @instance[:aws_state_code] = @text
          when 'name' then
            @instance[:aws_state] = @text
          when 'productCode' then
            @instance[:aws_product_codes] << @text
          when 'instanceType' then
            @instance[:aws_instance_type] = @text
          when 'launchTime' then
            @instance[:aws_launch_time] = @text
          when 'kernelId' then
            @instance[:aws_kernel_id] = @text
          when 'ramdiskId' then
            @instance[:aws_ramdisk_id] = @text
          when 'platform' then
            @instance[:aws_platform] = @text
          when 'availabilityZone' then
            @instance[:aws_availability_zone] = @text
          when 'privateIpAddress' then
            @instance[:aws_private_ip_address] = @text
          when 'subnetId' then
            @instance[:subnet_id] = @text
          when 'vpcId' then
            @instance[:vpc_id] = @text
          when 'key' then
            @tag_key = @text
          when 'value' then
            @tag_value = @text
          when 'deviceName' then
            @device_name = @text
          when 'volumeId' then
            @volume_id = @text
          when 'state'
            if @xmlpath == 'DescribeInstancesResponse/reservationSet/item/instancesSet/item/monitoring' || # DescribeInstances property
            @xmlpath == 'RunInstancesResponse/instancesSet/item/monitoring' # RunInstances property
              @instance[:monitoring_state] = @text
            end
          when 'item'
            if @xmlpath=='DescribeInstancesResponse/reservationSet/item/instancesSet/item/tagSet' # Tags
              @instance[:tags][@tag_key] = @tag_value
            elsif @xmlpath == 'DescribeInstancesResponse/reservationSet/item/instancesSet/item/blockDeviceMapping' # Block device mappings
              @instance[:block_device_mappings] << { @device_name => @volume_id }
            elsif @xmlpath == 'DescribeInstancesResponse/reservationSet/item/instancesSet' || # DescribeInstances property
            @xmlpath == 'RunInstancesResponse/instancesSet' # RunInstances property
              @reservation[:instances_set] << @instance
            elsif @xmlpath=='DescribeInstancesResponse/reservationSet' # DescribeInstances property
              @result << @reservation
            end
          when 'RunInstancesResponse' then
            @result << @reservation # RunInstances property
        end
      end

      def reset
        @result = []
      end
    end

    class QEc2ConfirmProductInstanceParser < AwsParser #:nodoc:
      def tagend(name)
        @result = @text if name == 'ownerId'
      end
    end

    class QEc2MonitorInstancesParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @instance = {} if name == 'item'
      end

      def tagend(name)
        case name
          when 'instanceId' then
            @instance[:aws_instance_id] = @text
          when 'state' then
            @instance[:aws_monitoring_state] = @text
          when 'item' then
            @result << @instance
        end
      end

      def reset
        @result = []
      end
    end

    class QEc2CreateImageParser < AwsParser #:nodoc:
      def tagend(name)
        @result = @text  if name == 'imageId'
      end
    end


    class QEc2TerminateInstancesParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @instance = {} if name == 'item'
      end

      def tagend(name)
        case name
          when 'instanceId' then
            @instance[:aws_instance_id] = @text
          when 'code'
            if @xmlpath == 'TerminateInstancesResponse/instancesSet/item/shutdownState'
              @instance[:aws_shutdown_state_code] = @text.to_i
            else
              @instance[:aws_prev_state_code] = @text.to_i
            end
          when 'name'
            if @xmlpath == 'TerminateInstancesResponse/instancesSet/item/shutdownState'
              @instance[:aws_shutdown_state] = @text
            else
              @instance[:aws_prev_state] = @text
            end
          when 'item' then
            @result << @instance
        end
      end

      def reset
        @result = []
      end
    end

    class QEc2StopInstancesParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @instance = {} if name == 'item'
      end

      def tagend(name)
        case name
          when 'instanceId' then
            @instance[:aws_instance_id] = @text
          when 'code'
            if @xmlpath == 'StopInstancesResponse/instancesSet/item/currentState'
              @instance[:aws_current_state_code] = @text.to_i
            elsif @xmlpath == 'StopInstancesResponse/instancesSet/item/previousState'
              @instance[:aws_prev_state_code] = @text.to_i
            end
          when 'name'
            if @xmlpath == 'StopInstancesResponse/instancesSet/item/currentState'
              @instance[:aws_current_state] = @text
            elsif @xmlpath == 'StopInstancesResponse/instancesSet/item/previousState'
              @instance[:aws_prev_state] = @text
            end
          when 'item' then
            @result << @instance
        end
      end

      def reset
        @result = []
      end
    end

    class QEc2StartInstancesParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @instance = {} if name == 'item'
      end

      def tagend(name)
        case name
          when 'instanceId' then
            @instance[:aws_instance_id] = @text
          when 'code'
            if @xmlpath == 'StartInstancesResponse/instancesSet/item/currentState'
              @instance[:aws_current_state_code] = @text.to_i
            elsif @xmlpath == 'StartInstancesResponse/instancesSet/item/previousState'
              @instance[:aws_prev_state_code] = @text.to_i
            end
          when 'name'
            if @xmlpath == 'StartInstancesResponse/instancesSet/item/currentState'
              @instance[:aws_current_state] = @text
            elsif @xmlpath == 'StartInstancesResponse/instancesSet/item/previousState'
              @instance[:aws_prev_state] = @text
            end
          when 'item' then
            @result << @instance
        end
      end

      def reset
        @result = []
      end
    end


    #-----------------------------------------------------------------
    #      PARSERS: Console
    #-----------------------------------------------------------------

    class QEc2GetConsoleOutputParser < AwsParser #:nodoc:
      def tagend(name)
        case name
          when 'instanceId' then
            @result[:aws_instance_id] = @text
          when 'timestamp' then
            @result[:aws_timestamp] = @text
            @result[:timestamp]     = (Time.parse(@text)).utc
          when 'output' then
            @result[:aws_output] = Base64.decode64(@text)
        end
      end

      def reset
        @result = {}
      end
    end

    #-----------------------------------------------------------------
    #      Instances: Wondows related part
    #-----------------------------------------------------------------
    class QEc2DescribeBundleTasksParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @bundle = {} if name == 'item'
      end

      def tagend(name)
        case name
#        when 'requestId'  then @bundle[:request_id]    = @text
          when 'instanceId' then
            @bundle[:aws_instance_id] = @text
          when 'bundleId' then
            @bundle[:aws_id] = @text
          when 'bucket' then
            @bundle[:s3_bucket] = @text
          when 'prefix' then
            @bundle[:s3_prefix] = @text
          when 'startTime' then
            @bundle[:aws_start_time] = @text
          when 'updateTime' then
            @bundle[:aws_update_time] = @text
          when 'state' then
            @bundle[:aws_state] = @text
          when 'progress' then
            @bundle[:aws_progress] = @text
          when 'code' then
            @bundle[:aws_error_code] = @text
          when 'message' then
            @bundle[:aws_error_message] = @text
          when 'item' then
            @result << @bundle
        end
      end

      def reset
        @result = []
      end
    end

    class QEc2BundleInstanceParser < AwsParser #:nodoc:
      def tagend(name)
        case name
#        when 'requestId'  then @result[:request_id]    = @text
          when 'instanceId' then
            @result[:aws_instance_id] = @text
          when 'bundleId' then
            @result[:aws_id] = @text
          when 'bucket' then
            @result[:s3_bucket] = @text
          when 'prefix' then
            @result[:s3_prefix] = @text
          when 'startTime' then
            @result[:aws_start_time] = @text
          when 'updateTime' then
            @result[:aws_update_time] = @text
          when 'state' then
            @result[:aws_state] = @text
          when 'progress' then
            @result[:aws_progress] = @text
          when 'code' then
            @result[:aws_error_code] = @text
          when 'message' then
            @result[:aws_error_message] = @text
        end
      end

      def reset
        @result = {}
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: Elastic IPs
    #-----------------------------------------------------------------

    class QEc2AllocateAddressParser < AwsParser #:nodoc:
      def tagend(name)
        @result = @text if name == 'publicIp'
      end
    end

    class QEc2DescribeAddressesParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @address = {} if name == 'item'
      end

      def tagend(name)
        case name
          when 'instanceId' then
            @address[:instance_id] = Aws::Utils.blank?(@text) ? nil : @text
          when 'publicIp' then
            @address[:public_ip] = @text
          when 'item' then
            @result << @address
        end
      end

      def reset
        @result = []
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: AvailabilityZones
    #-----------------------------------------------------------------

    class QEc2DescribeAvailabilityZonesParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @zone = {} if name == 'item'
      end

      def tagend(name)
        case name
          when 'regionName' then
            @zone[:region_name] = @text
          when 'zoneName' then
            @zone[:zone_name] = @text
          when 'zoneState' then
            @zone[:zone_state] = @text
          when 'item' then
            @result << @zone
        end
      end

      def reset
        @result = []
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: Regions
    #-----------------------------------------------------------------

    class QEc2DescribeRegionsParser < AwsParser #:nodoc:
      def tagend(name)
        @result << @text if name == 'regionName'
      end

      def reset
        @result = []
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: EBS - Volumes
    #-----------------------------------------------------------------

    class QEc2CreateVolumeParser < AwsParser #:nodoc:
      def tagend(name)
        case name
          when 'volumeId' then
            @result[:aws_id] = @text
          when 'status' then
            @result[:aws_status] = @text
          when 'createTime' then
            @result[:aws_created_at] = Time.parse(@text)
          when 'size' then
            @result[:aws_size] = @text.to_i ###
          when 'snapshotId' then
            @result[:snapshot_id] = Aws::Utils.blank?(@text) ? nil : @text ###
          when 'availabilityZone' then
            @result[:zone] = @text ###
        end
      end

      def reset
        @result = {}
      end
    end

    class QEc2AttachAndDetachVolumeParser < AwsParser #:nodoc:
      def tagend(name)
        case name
          when 'volumeId' then
            @result[:aws_id] = @text
          when 'instanceId' then
            @result[:aws_instance_id] = @text
          when 'device' then
            @result[:aws_device] = @text
          when 'status' then
            @result[:aws_attachment_status] = @text
          when 'attachTime' then
            @result[:aws_attached_at] = Time.parse(@text)
        end
      end

      def reset
        @result = {}
      end
    end

    class QEc2DescribeVolumesParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        case name
          when 'item'
            case @xmlpath
              when 'DescribeVolumesResponse/volumeSet' then
                @volume = {}
            end
        end
      end

      def tagend(name)
        case name
          when 'volumeId'
            case @xmlpath
              when 'DescribeVolumesResponse/volumeSet/item' then
                @volume[:aws_id] = @text
            end
          when 'status'
            case @xmlpath
              when 'DescribeVolumesResponse/volumeSet/item' then
                @volume[:aws_status] = @text
              when 'DescribeVolumesResponse/volumeSet/item/attachmentSet/item' then
                @volume[:aws_attachment_status] = @text
            end
          when 'size' then
            @volume[:aws_size] = @text.to_i
          when 'createTime' then
            @volume[:aws_created_at] = Time.parse(@text)
          when 'instanceId' then
            @volume[:aws_instance_id] = @text
          when 'device' then
            @volume[:aws_device] = @text
          when 'attachTime' then
            @volume[:aws_attached_at] = Time.parse(@text)
          when 'snapshotId' then
            @volume[:snapshot_id] = Aws::Utils.blank?(@text) ? nil : @text
          when 'availabilityZone' then
            @volume[:zone] = @text
          when 'item'
            case @xmlpath
              when 'DescribeVolumesResponse/volumeSet' then
                @result << @volume
            end
        end
      end

      def reset
        @result = []
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: EBS - Snapshots
    #-----------------------------------------------------------------

    class QEc2DescribeSnapshotsParser < AwsParser #:nodoc:

      def initialize (params={})
        @inside_tagset = false
        super(params)
      end

      def tagstart(name, attributes)
        case name
          when 'tagSet'
            @inside_tagset = true
          when 'item'
            @snapshot = {} unless @inside_tagset
        end
      end

      def tagend(name)
        case name
          when 'volumeId' then
            @snapshot[:aws_volume_id] = @text
          when 'snapshotId' then
            @snapshot[:aws_id] = @text
          when 'status' then
            @snapshot[:aws_status] = @text
          when 'startTime' then
            @snapshot[:aws_started_at] = Time.parse(@text)
          when 'progress' then
            @snapshot[:aws_progress] = @text
          when 'description' then
            @snapshot[:aws_description] = @text
          when 'ownerId' then
            @snapshot[:aws_owner] = @text
          when 'volumeSize' then
            @snapshot[:aws_volume_size] = @text.to_i
          when 'tagSet' then
            @inside_tagset = false
          when 'key' then
            @key = ('aws_tag_' + @text).to_sym
          when 'value' then
            @snapshot[@key] = @text
          when 'item' then
            @result << @snapshot unless @inside_tagset
        end
      end

      def reset
        @result = []
      end
    end

    class QEc2CreateSnapshotParser < AwsParser #:nodoc:
      def tagend(name)
        case name
          when 'volumeId' then
            @result[:aws_volume_id] = @text
          when 'snapshotId' then
            @result[:aws_id] = @text
          when 'status' then
            @result[:aws_status] = @text
          when 'startTime' then
            @result[:aws_started_at] = Time.parse(@text)
          when 'progress' then
            @result[:aws_progress] = @text
        end
      end

      def reset
        @result = {}
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: Tags
    #-----------------------------------------------------------------

    class QEc2DescribeTagsParser < AwsParser #:nodoc:
      def tagstart(name, attributes)
        @tag = {} if name == 'item'
      end

      def tagend(name)
        case name
          when 'resourceId' then
            @tag[:aws_resource_id] = @text
          when 'resourceType' then
            @tag[:aws_resource_type] = @text
          when 'key' then
            @tag[:aws_key] = @text
          when 'value' then
            @tag[:aws_value] = @text
          when 'item' then
            @result << @tag
        end
      end

      def reset
        @result = []
      end
    end

    #-----------------------------------------------------------------
    #      PARSERS: Vpc
    #-----------------------------------------------------------------

    class QEc2VpcsParser < AwsParser #:nodoc:
      def initialize(wrapper, opts = {})
        super(opts)
        @wrapper = wrapper
      end

      def tagstart(name, attribute)
        @vpc = {} if name == @wrapper
      end

      def tagend(name)
        case name
          when 'vpcId' then
            @vpc[:vpc_id] = @text
          when 'state' then
            @vpc[:state] = @text
          when 'cidrBlock' then
            @vpc[:cidr_block] = @text
          when 'dhcpOptionsId' then
            @vpc[:dhcp_options_id] = @text
          when @wrapper
            @result << @vpc
        end
      end

      def reset
        @result = []
      end
    end

    class QEc2NetworkInterfacesParser < AwsParser #:nodoc:
      def initialize(opts = {})
        super(opts)
        @level = ['top']
      end

      def tagstart(name, attribute)
        case name
        when 'groupSet'
          @level.push(name)
          @iface[:group_set] = []
          @group_item = {}
        when 'attachment'
          @level.push(name)
          @iface[:attachment] = {}
        when 'tagSet'
          @level.push(name)
          @iface[:tag_set] = []
          @tag_set_item = {}
        when 'association'
          @level.push(name)
          @association = {}
        when 'privateIpAddressesSet'
          @level.push(name)
          @iface[:private_ip_addresses_set] = []
          @ip_address_item = {}
        when 'networkInterface'
          @iface = {}
        when 'item'
          @iface = {} if @level.last == 'top'
        end
      end

      def tagend(name)
        wrapper = @level.last
        case wrapper
        when 'top'  # parse top level
          case name
          when 'networkInterfaceId'
            @iface[:network_interface_id] = @text
          when 'subnetId'
            @iface[:subnet_id] = @text
          when 'vpcId'
            @iface[:vpc_id] = @text
          when 'availabilityZone'
            @iface[:availability_zone] = @text
          when 'description'
            @iface[:description] = @text
          when 'ownerId'
            @iface[:owner_id] = @text
          when 'requesterId'
            @iface[:requester_id] = @text
          when 'requesterManaged'
            @iface[:requester_managed] = @text
          when 'status'
            @iface[:status] = @text
          when 'macAddress'
            @iface[:mac_address] = @text
          when 'privateIpAddress'
            @iface[:private_ip_address] = @text
          when 'privateDnsName'
            @iface[:private_dns_name] = @text
          when 'sourceDestCheck'
            @iface[:source_dest_check] = @text
          when 'networkInterface'
            @result = @iface
          when 'item'
            @result << @iface
          end
        when 'groupSet'  # parse gorupset
          case name
          when 'groupId'
            @group_item[:group_id] = @text
          when 'groupName'
            @group_item[:group_name] = @text
          when 'item'
            @iface[:group_set] << @group_item
            @group_item = {}
          when 'groupSet'
            @level.pop
          end
        when 'attachment'  # parse attachment
          case name
          when 'attachmentId'
            @iface[:attachment][:attachment_id] = @text
          when 'instanceId'
            @iface[:attachment][:instance_id] = @text
          when 'instanceOwnerId'
            @iface[:attachment][:instance_owner_id] = @text
          when 'deviceIndex'
            @iface[:attachment][:device_index] = @text
          when 'status'
            @iface[:attachment][:status] = @text
          when 'attachTime'
            @iface[:attachment][:attach_time] = @text
          when 'deleteOnTermination'
            @iface[:attachment][:delete_on_termination] = @text
          when 'attachment'
            @level.pop
          end
        when 'tagSet'  # parse tagset
          case name
          when 'key'
            @tag_set_item[:key] = @text
          when 'value'
            @tag_set_item[:value] = @text
          when 'item'
            @iface[:tag_set] << @tag_set_item
            @tag_set_item = {}
          when 'tagSet'
            @level.pop
          end
        when 'association'  # parse assoc
          case name
          when 'publicIp'
            @association[:public_ip] = @text
          when 'publicDnsName'
            @association[:public_dns_name] = @text
          when 'ipOwnerId'
            @association[:ip_owner_id] = @text
          when 'allocationID'
            @association[:allocation_id] = @text
          when 'associationID'
            @association[:association_id] = @text
          when 'association'
            @level.pop

            # `association` can belong both to `NetworkInterfaceType` and `NetworkInterfacePrivateIpAddressesSetItemType`
            if @level.last == 'top'
              @iface[:association] = @association
            else
              @ip_address_item[:association] = @association
            end
          end
        when 'privateIpAddressesSet'  # parse pirvate addresses set
          case name
          when 'privateIpAddress'
            @ip_address_item[:private_ip_address] = @text
          when 'privateDnsName'
            @ip_address_item[:private_dns_name] = @text
          when 'primary'
            @ip_address_item[:primary] = @text
          when 'item'
            @iface[:private_ip_addresses_set] << @ip_address_item
            @ip_address_item = {}
          when 'privateIpAddressesSet'
            @level.pop
          end
        end
      end

      def reset
        @result = []
      end
    end

    class QEc2AttachNetworkInterfaceParser < AwsParser #:nodoc:
      def initialize(opts = {})
        super(opts)
      end

      def tagend(name)
        case name
        when 'attachmentId'
          @result['attachment_id'] = @text
        end
      end

      def reset
        @result = {}
      end
    end

    class QEc2SubnetsParser < AwsParser #:nodoc
      def initialize(wrapper, opts = {})
        super(opts)
        @wrapper = wrapper
      end

      def tagstart(name, attribute)
        @subnet = {} if name == @wrapper
      end

      def tagend(name)
        case name
          when 'subnetId' then
            @subnet[:subnet_id] = @text
          when 'state' then
            @subnet[:state] = @text
          when 'vpcId' then
            @subnet[:vpc_id] = @text
          when 'cidrBlock' then
            @subnet[:cidr_block] = @text
          when 'availableIpAddressCount' then
            @subnet[:available_ip_address_count] = @text
          when 'availabilityZone' then
            @subnet[:availability_zone] = @text
          when @wrapper
            @result << @subnet
        end
      end

      def reset
        @result = []
      end
    end
  end

end