Module: VMTools

Defined in:
lib/vm_tools.rb

Class Method Summary collapse

Class Method Details

.ensure_keyname_not_in_use(keyname, infrastructure) ⇒ Object 



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# File 'lib/vm_tools.rb', line 108

def self.ensure_keyname_not_in_use(keyname, infrastructure)
  describe_instances = CommonFunctions.shell("#{infrastructure}-describe-instances 2>&1")
  if describe_instances =~ /\s#{keyname}\s/
    raise InfrastructureException.new("The keyname you chose is " +
      "already in use. Please choose another keyname and try again.")
  end
end

.ensure_min_vms_available(min_vms_needed, instance_type, infrastructure) ⇒ Object 



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# File 'lib/vm_tools.rb', line 116

def self.ensure_min_vms_available(min_vms_needed, instance_type, infrastructure)
  puts "warn: this doesn't work on ec2 - euca only"
  availability_zones = CommonFunctions.shell("#{infrastructure}-describe-availability-zones verbose 2>&1")
  # check for errors from last command
  vms_str = availability_zones.scan(/#{instance_type}\t([\d]+)/).flatten.to_s
  if vms_str.nil? or vms_str.empty?
    raise InfrastructureException.new("There was a problem seeing how many " +
      "virtual machines were available. We saw [#{availability_zones}].")
  end

  free_vms = Integer(vms_str)
  if free_vms < min_vms_needed
    raise InfrastructureException.new("Not enough VMs were free of the " +
      "type #{instance_type}. Needed #{min_vms_needed} but only #{free_vms}" +
      " were available.")
  end
end

.ensure_tools_are_installed(infrastructure) ⇒ Object 



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# File 'lib/vm_tools.rb', line 87

def self.ensure_tools_are_installed(infrastructure)
  commands = ["-add-group", "-authorize", "-describe-instances", "-run-instances", "-terminate-instances"]
  commands.each { |cmd|
    full_cmd = "#{infrastructure}#{cmd}"
    if !CommonFunctions.user_has_cmd?(full_cmd)
      raise BadConfigurationException.new("You do not appear to " +
        "have the command '#{full_cmd}'. Please put it in your PATH and " +
        "try again.")
    end
  }
end

.get_cloud_creds(node_layout, val_hash) ⇒ Object 



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# File 'lib/vm_tools.rb', line 376

def self.get_cloud_creds(node_layout, val_hash)
  cloud_creds = {
    "machine" => "#{val_hash['machine']}",
    "instance_type" => "#{val_hash['instance_type']}",
    "infrastructure" => "#{val_hash['infrastructure']}",
    "min_images" => "#{node_layout.min_images}",
    "max_images" => "#{node_layout.max_images}"
  }

  EC2_ENVIRONMENT_VARIABLES.each { |var|
    cloud_creds["CLOUD1_#{var}"] = ENV[var]
  }

  if cloud_creds["infrastructure"] == "euca"
    ["EC2_URL", "S3_URL"].each { |var|
      cloud_creds["CLOUD1_#{var}"] = ENV[var]
    }
  end

  cloud_creds.merge!(VMTools.get_creds_from_env)
  return cloud_creds
end

.get_creds_from_env ⇒ Object 



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# File 'lib/vm_tools.rb', line 65

def self.get_creds_from_env
  creds = {}
  optional = {"ec2_url" => "https://us-east-1.ec2.amazonaws.com"}
  required = ["ec2_access_key", "ec2_secret_key"]

  optional.each { |k, v|
    creds[k] = ENV[k.upcase] or v
  }

  required.each { |var|
    if ENV[var.upcase]
      creds[var] = ENV[var.upcase]
    else
      raise BadConfigurationException.new("The required " +
        "environment variable #{var.upcase} was not set. Please set it " +
        "and try running AppScale again.")
    end
  }

  return creds
end

.get_hybrid_creds(node_layout, set_head_node_creds = false) ⇒ Object 



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# File 'lib/vm_tools.rb', line 420

def self.get_hybrid_creds(node_layout, set_head_node_creds=false)
  cloud_creds = {
    "infrastructure" => "hybrid",
    "min_images" => "#{node_layout.min_images}",
    "max_images" => "#{node_layout.max_images}"
  }

  cloud_num = 1
  loop {
    cloud_type = ENV["CLOUD#{cloud_num}_TYPE"] 
    break if cloud_type.nil?

    if cloud_num == 1 and set_head_node_creds
      set_vars = true
    else
      set_vars = false
    end

    cloud_creds.merge!(self.get_hybrid_env_vars(cloud_type, cloud_num, set_vars))
    cloud_num += 1 
  }

  return cloud_creds
end

.get_hybrid_env_vars(cloud_type, cloud_num, set_vars = false) ⇒ Object 



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# File 'lib/vm_tools.rb', line 449

def self.get_hybrid_env_vars(cloud_type, cloud_num, set_vars=false)
  creds = {}

  if cloud_type == "euca"
    required = REQUIRED_EUCA_CREDS_FOR_HYBRID
  elsif cloud_type == "ec2"
    required = REQUIRED_EC2_CREDS_FOR_HYBRID
  else
    puts "Incorrect cloud type of #{cloud_type}"
    fail
  end

  required.each { |cred|
    key = "CLOUD#{cloud_num}_#{cred}"
    val = ENV[key]

    if val.nil?
      raise BadConfigurationException.new("The required " +
        "environment variable #{key} was not set. Please set it and " +
        "try again.")
    end

    if set_vars
      puts "Setting #{cred} to #{val}"
      ENV[cred] = val
    end

    creds[key] = val
  }

  return creds
end

.get_hybrid_machine(infra, cloud_num) ⇒ Object 



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# File 'lib/vm_tools.rb', line 482

def self.get_hybrid_machine(infra, cloud_num)
  if infra == "euca"
    key = "CLOUD#{cloud_num}_EMI"
  elsif infra == "ec2"
    key = "CLOUD#{cloud_num}_AMI"
  else
    raise BadConfigurationException.new("infrastructure #{infra} " +
      "is not a supported value.")
  end

  return ENV[key]
end

.get_initial_layout(head_node, separate, num_of_nodes, total_nodes) ⇒ Object 



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# File 'lib/vm_tools.rb', line 44

def self.get_initial_layout(head_node, separate, num_of_nodes, total_nodes)
  if head_node
    if separate
      raise NotImplementedError.new("haven't done head node, separate yet")
    else
      layout = "shadow:load_balancer:db_master"
      layout << ":appengine" if total_nodes == 1
    end
  else
    raise NotImplementedError.new("haven't done slave nodes, separate yet")
  end

  return layout
end

.get_ips(ips, verbose) ⇒ Object 



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# File 'lib/vm_tools.rb', line 159

def self.get_ips(ips, verbose)
  if ips.length % 2 != 0
    raise InfrastructureException.new("ips not even length array")
  end
  reported_public = []
  reported_private = []
  ips.each_index { |index|
    if index % 2 == 0
      reported_public << ips[index]
    else
      reported_private << ips[index]
    end
  }
  
  if verbose
    puts "Reported Public IPs: [#{reported_public.join(', ')}]"
    puts "Reported Private IPs: [#{reported_private.join(', ')}]"
  end
  
  actual_public = []
  actual_private = []
  
  reported_public.each_index { |index|
    pub = reported_public[index]
    pri = reported_private[index]
    if pub != "0.0.0.0" and pri != "0.0.0.0"
      actual_public << pub
      actual_private << pri
    end
  }
  
  return actual_public, actual_private
end

.get_public_ips(ips, verbose) ⇒ Object 



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# File 'lib/vm_tools.rb', line 193

def self.get_public_ips(ips, verbose)
  if ips.length % 2 != 0
    raise InfrastructureException.new("ips not even length array")
  end

  reported_public = []
  reported_private = []
  ips.each_index { |index|
    if index % 2 == 0
      reported_public << ips[index]
    else
      reported_private << ips[index]
    end
  }
  
  puts "Reported Public IPs: [#{reported_public.join(', ')}]" if verbose
  puts "Reported Private IPs: [#{reported_private.join(', ')}]" if verbose
  
  public_ips = []
  reported_public.each_index { |index|
    if reported_public[index] != "0.0.0.0"
      public_ips << reported_public[index]
    elsif reported_private[index] != "0.0.0.0"
      public_ips << reported_private[index]
    end
  }
  
  return public_ips.flatten
end

.get_vmm_keys(val_hash) ⇒ Object 



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# File 'lib/vm_tools.rb', line 399

def self.get_vmm_keys(val_hash)
  puts "Generating certificate and private key"
  key, cert = EncryptionHelper.generate_pem_files(val_hash['keyname'])
  key = File.expand_path("~/.appscale/#{val_hash['keyname']}-key.pem")
  cert = File.expand_path("~/.appscale/#{val_hash['keyname']}-cert.pem")

  return cert, key
end

.local_ip ⇒ Object

Code for local_ip taken from coderrr.wordpress.com/2008/05/28/get-your-local-ip-address/



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# File 'lib/vm_tools.rb', line 61

def self.local_ip
  UDPSocket.open {|s| s.connect("64.233.187.99", 1); s.addr.last }
end

.lookup_cloud_env(cloud) ⇒ Object 



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# File 'lib/vm_tools.rb', line 408

def self.lookup_cloud_env(cloud)
  cloud_type_var = cloud.upcase + "_TYPE"
  cloud_type = ENV[cloud_type_var]

  if cloud_type.nil?
    raise BadConfigurationException.new("The environment variable " +
      "#{cloud_type_var} was not set. Please set it and try again.")
  end

  return cloud_type
end

.open_ports_in_cloud(infrastructure, group, verbose) ⇒ Object 



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# File 'lib/vm_tools.rb', line 99

def self.open_ports_in_cloud(infrastructure, group, verbose)
  retn = CommonFunctions.shell("#{infrastructure}-authorize #{group} -p 1-65535 -s 0.0.0.0/0 -P udp 2>&1")
  puts retn if verbose
  retn = CommonFunctions.shell("#{infrastructure}-authorize #{group} -p 1-65535 -s 0.0.0.0/0 -P tcp 2>&1")
  puts retn if verbose
  retn = CommonFunctions.shell("#{infrastructure}-authorize #{group} -s 0.0.0.0/0 -P icmp -t -1:-1 2>&1")
  puts retn if verbose
end

.set_hybrid_creds(node_layout) ⇒ Object 



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# File 'lib/vm_tools.rb', line 445

def self.set_hybrid_creds(node_layout)
  return self.get_hybrid_creds(node_layout, set_head_node_creds=true)
end

.spawn_head_node(head_node, infrastructure, keyname, ssh_key_location, ssh_keys, force, machine, instance_type, group, verbose) ⇒ Object 



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# File 'lib/vm_tools.rb', line 327

def self.spawn_head_node(head_node, infrastructure, keyname, 
  ssh_key_location, ssh_keys, force, machine, instance_type, group, verbose)

  head_node_jobs = head_node.roles.join(":")
  if VALID_CLOUD_TYPES.include?(infrastructure)
    VMTools.spawn_head_node_via_cloud(infrastructure, keyname, 
      ssh_key_location, ssh_keys, force, head_node_jobs, machine, 
      instance_type, group, verbose)
  else
    VMTools.spawn_head_node_via_vmm(head_node, keyname, head_node_jobs)
  end
end

.spawn_head_node_via_cloud(infrastructure, keyname, ssh_key_location, ssh_keys, force, head_node_jobs, machine, instance_type, group, verbose) ⇒ Object 



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# File 'lib/vm_tools.rb', line 340

def self.spawn_head_node_via_cloud(infrastructure, keyname, 
  ssh_key_location, ssh_keys, force, head_node_jobs, machine, 
  instance_type, group, verbose)

  VMTools.ensure_tools_are_installed(infrastructure)
  #VMTools.verify_ids(machine, infrastructure)
  VMTools.ensure_keyname_not_in_use(keyname, infrastructure)
  #VMTools.ensure_min_vms_available(min_images, instance_type, infrastructure)
  EncryptionHelper.generate_ssh_key(verbose, ssh_keys, keyname, infrastructure, force)
  locations = VMTools.spawn_vms(1, head_node_jobs, machine, instance_type, keyname, infrastructure, group, verbose)
  puts "Please wait for your instance to complete the bootup process."
  head_node_ip = locations[0].split(":")[0]
  CommonFunctions.sleep_until_port_is_open(head_node_ip, AppScaleTools::SSH_PORT)
  sleep(10)
  options = "-o StrictHostkeyChecking=no -o NumberOfPasswordPrompts=0"
   = "sudo cp /home/ubuntu/.ssh/authorized_keys /root/.ssh/"
  `ssh -i #{ssh_keys.join(" -i ")} #{options} 2>&1 ubuntu@#{head_node_ip} '#{}'` # kloogy ec2 fix
  CommonFunctions.scp_file(ssh_key_location, "/root/.ssh/id_dsa", head_node_ip, ssh_keys) # kloogy ec2 fix
  CommonFunctions.scp_file(ssh_key_location, "/root/.ssh/id_rsa", head_node_ip, ssh_keys)
  CommonFunctions.shell("scp -i #{ssh_keys.join(" -i ")} -o StrictHostkeyChecking=no 2>&1 root@#{head_node_ip}:/root/.ssh/authorized_keys /tmp/remote_keys")
  remote_keys = (File.open("/tmp/remote_keys") { |f| f.read }).chomp
  public_key_contents = remote_keys.scan(/ssh-rsa [\w+\/=]+ [\w@]+/).flatten.to_s
  File.open("/tmp/id_rsa.pub", "w+") { |file| file.write(public_key_contents) }  
  CommonFunctions.scp_file("/tmp/id_rsa.pub", "/root/.ssh/id_rsa.pub", head_node_ip, ssh_keys)  
  locations = locations.flatten.to_s
  return locations
end

.spawn_head_node_via_vmm(node, keyname, head_node_jobs) ⇒ Object 



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# File 'lib/vm_tools.rb', line 368

def self.spawn_head_node_via_vmm(node, keyname, head_node_jobs)
  # We don't care about the instance's ID if not using cloud-tools
  # and for Xen, public ip = private ip
  head_node = "#{node.id}:#{node.id}:#{head_node_jobs}:i-ZFOOBARZ:cloud1"
  locations = [head_node].flatten.to_s
  return locations
end

.spawn_vms(num_of_vms_to_spawn, job, image_id, instance_type, keyname, infrastructure, group, verbose) ⇒ Object 



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# File 'lib/vm_tools.rb', line 223

def self.spawn_vms(num_of_vms_to_spawn, job, image_id, instance_type, keyname,
  infrastructure, group, verbose)
  #adding check first so that we don't do any of this if the infrastructure setting is wrong
  if !VALID_CLOUD_TYPES.include?(infrastructure)
    raise BadConfigurationException.new("Infrastructure must be " +
      "iaas, ec2, or euca, but instead was #{infrastructure}")
  end

  if infrastructure == "ec2"
  	check_group = CommonFunctions.shell("#{infrastructure}-describe-group #{group} 2>&1")
  	make_group = check_group.include? 'InvalidGroup.NotFound'
  elsif infrastructure == "euca"
  	check_group = CommonFunctions.shell("#{infrastructure}-describe-groups #{group} 2>&1")
  	make_group = check_group.empty?
  end
  if make_group
     puts "Creating security group #{group}" if verbose
     create_sec_group = CommonFunctions.shell("#{infrastructure}-add-group #{group} -d #{group} 2>&1")
     puts create_sec_group if verbose
  else # security group exists
    raise InfrastructureException.new("Security group #{group} exists, " +
      "delete this group via #{infrastructure}-delete-group #{group}, " +
      "prior to starting an AppScale cloud")
  end
  puts "Security group #{group} in place" if verbose
  VMTools.open_ports_in_cloud(infrastructure, group, verbose)
  puts "Ports set for security group #{group}" if verbose
  
  describe_instances = CommonFunctions.shell("#{infrastructure}-describe-instances 2>&1")
  puts describe_instances if verbose
  all_ip_addrs = describe_instances.scan(/\s+(#{IP_OR_FQDN})\s+(#{IP_OR_FQDN})\s+running\s+#{keyname}\s/).flatten
  ips_up_already = VMTools.get_public_ips(all_ip_addrs, verbose)
  vms_up_already = ips_up_already.length  

  command_to_run = "#{infrastructure}-run-instances -k #{keyname} -n #{num_of_vms_to_spawn} --instance-type #{instance_type} --group #{group} #{image_id}" 
  
  puts command_to_run if verbose
  run_instances = ""
  loop {
    run_instances = CommonFunctions.shell("#{command_to_run} 2>&1")
    puts "run_instances: [#{run_instances}]" if verbose
    if run_instances =~ /Please try again later./
      puts "Error with run_instances: #{run_instances}. Will try again in a moment."
    elsif run_instances =~ /try --addressing private/
      puts "Need to retry with addressing private. Will try again in a moment."
      command_to_run << " --addressing private"
    elsif run_instances =~ /PROBLEM/
      raise InfrastructureException.new("Saw the following error message " +
        "from iaas tools. Please resolve the issue and try again:\n" +
        "#{run_instances}")
    else
      puts "Run instances message sent successfully. Waiting for the image to start up."
      break
    end
  }
  
  instance_ids = run_instances.scan(/INSTANCE\s+(i-\w+)\s+[\w\-\s\.]+#{keyname}\s/).flatten
   
  end_time = Time.now + MAX_VM_CREATION_TIME
  while (now = Time.now) < end_time
    describe_instances = CommonFunctions.shell("#{infrastructure}-describe-instances 2>&1")
    puts "[#{Time.now}] #{end_time - now} seconds left until timeout..."
    puts describe_instances if verbose
    
    if describe_instances =~ /terminated\s#{keyname}\s/
      raise InfrastructureException.new("An instance was unexpectedly " +
        "terminated. Please contact your cloud administrator to determine " +
        "why and try again. \n#{describe_instances}")
    end
    
    all_ip_addrs = describe_instances.scan(/\s+(#{IP_OR_FQDN})\s+(#{IP_OR_FQDN})\s+running\s+#{keyname}\s/).flatten
    instance_ids = describe_instances.scan(/INSTANCE\s+(i-\w+)\s+[\w\-\s\.]+#{keyname}\s/).flatten
    public_ips, private_ips = VMTools.get_ips(all_ip_addrs, verbose)
    break if public_ips.length == num_of_vms_to_spawn + vms_up_already
    sleep(SLEEP_TIME)
  end
  
  if public_ips.length.zero?
    raise InfrastructureException.new("No public IPs were able to be " +
      "procured within the time limit.")
  end
     
  if public_ips.length != instance_ids.length
    puts "Public IPs: #{public_ips.join(', ')}, Instance ids: #{instance_ids.join(', ')}"
    raise InfrastructureException.new("Public IPs size didn't match " +
      "instance names size")
  end

  instances_created = []
  public_ips.each_index { |index|
    instances_created << "#{public_ips[index]}:#{private_ips[index]}:#{job}:#{instance_ids[index]}:cloud1"
  }
  
  return instances_created    
end

.terminate_all_vms(keyname, infrastructure) ⇒ Object 



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# File 'lib/vm_tools.rb', line 319

def self.terminate_all_vms(keyname, infrastructure)
  desc_instances = CommonFunctions.shell("#{infrastructure}-describe-instances 2>&1")
  instances = desc_instances.scan(/INSTANCE\s+(i-\w+)\s+[\w\-\s\.]+#{keyname}\s/).flatten
  return 0 if instances.length == 0
  puts CommonFunctions.shell("#{infrastructure}-terminate-instances #{instances.join(' ')} 2>&1")
  return instances.length
end

.terminate_infrastructure_machines(infrastructure, keyname) ⇒ Object 



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# File 'lib/vm_tools.rb', line 532

def self.terminate_infrastructure_machines(infrastructure, keyname)
  # TODO: if we know all the other ips in the system, contact one
  # of them instead

  if keyname == "appscale"  # appscale keyname messes up the next command
    abort("Error seen trying to terminate your machines - please do so manually.")
  end

  # for now, just kill them the hard way
  desc = "#{infrastructure}-describe-instances"
  term = "#{infrastructure}-terminate-instances"
  cmd = "#{desc} | grep #{keyname} | awk '{print $2}' | xargs #{term}"
  puts "Unable to contact shadow node, shutting down via tools..."
  puts `#{cmd}`
  cmd = "#{infrastructure}-delete-group appscale"
  puts `#{cmd}`
end

.verify_credentials_are_set_correctly(infrastructure) ⇒ Object 



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# File 'lib/vm_tools.rb', line 495

def self.verify_credentials_are_set_correctly(infrastructure)
  # In non-hybrid cloud environments, the user has to provide us with their
  # EC2 credentials. If they didn't, let them know and abort.
  EC2_ENVIRONMENT_VARIABLES.each { |var|
    if ENV[var].nil?
      raise BadConfigurationException.new("The required " +
        "environment variable #{var} was not set. Please set it and try " +
        "again.")
    end
  }
 
  VMTools.verify_credentials_exist()
 
  # The euca2ools default to using localhost as the EC2_URL and S3_URL if
  # it's not set, so make sure the user has explicitly set it.
  if infrastructure == "euca"
    ['EC2_URL', 'S3_URL'].each { |var|
      if ENV[var].nil?
        raise BadConfigurationException.new("When running over " +
          "Eucalyptus, the environment variable #{var} must be set.")
      end
    }
  end
end

.verify_credentials_exist ⇒ Object

Validates that the private key and certificate for use with EC2 or Eucalyptus both refer to files that exist, aborting if either do not exist.



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# File 'lib/vm_tools.rb', line 522

def self.verify_credentials_exist()
  ["EC2_PRIVATE_KEY", "EC2_CERT"].each { |var|
    file_path = File.expand_path(ENV[var])
    if !File.exists?(file_path)
      raise BadConfigurationException.new("The environment variable" +
        " #{var} pointed to the file #{file_path}, which didn't exist.")
    end
  }
end

.verify_ids(disk, infrastructure) ⇒ Object 



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# File 'lib/vm_tools.rb', line 134

def self.verify_ids(disk, infrastructure)
  ec2_images = CommonFunctions.shell("#{infrastructure}-describe-images 2>&1")

  if disk !~ /[a|e]mi/
    raise InfrastructureException.new("The disk image you specified was " +
      "not in the proper format. Please correct this and try again.")
  end

  # if the tools are not configured properly an error message will show up
  # be sure to catch it and die if so
  if ec2_images =~ /\AServer:/
    raise InfrastructureException.new("Problem with " +
      "#{infrastructure}-tools: " + ec2_images)
  end

  id = "disk"
  id_value = eval(id)
  if ec2_images !~ /IMAGE\t#{id_value}/
    raise InfrastructureException.new("The #{id} image you specified, " +
      "#{id_value}, was not found when querying " +
      "#{infrastructure}-describe-images. Please specify a #{id} image in " +
      "the database and try again.")
  end
end