Class: AWS::EC2::InstanceCollection

Inherits:
Collection
  • Object
show all
Defined in:
lib/aws/ec2/instance_collection.rb

Overview

Represents a collection of EC2 instances. Typically you should get an instance of this class by calling #instances.

To run an instance:

ec2.instances.create(:image_id => "ami-8c1fece5")

To get an instance by ID:

i = ec2.instances["i-12345678"]
i.exists?

To get a map of instance IDs to instance status:

ec2.instances.inject({}) { |m, i| m[i.id] = i.status; m }
# => { "i-12345678" => :running, "i-87654321" => :shutting_down }

Instance Method Summary collapse

Instance Method Details

#[](id) ⇒ Instance

Returns an object representing the EC2 instance with the given ID.

Returns:

  • (Instance) —

    Returns an object representing the EC2 instance with the given ID.



239
240
241
 
# File 'lib/aws/ec2/instance_collection.rb', line 239

def [] id
  super
end

#create(options = {}) ⇒ Instance or Array Also known as: run

Runs one or more EC2 instances.

sleep 1 while instances.any? {|i| i.status == :pending }

Examples:

Running a single instance

i = ec2.instances.create(:image_id => "ami-8c1fece5")
sleep 1 while i.status == :pending

Running multiple instances with the same parameters


instances = ec2.instances.create(
  :image_id => "ami-8c1fece5",
  :count => 10)

Specifying block device mappings


ec2.instances.create({
  :image_id => "ami-8c1fece5",
  :block_device_mappings => {
    "/dev/sda2" => {
      :volume_size => 15, # 15 GiB
      :delete_on_termination => true
    }
  }
})

Parameters:

  • options (Hash) (defaults to: {}) —

    Options for new instance. :image_id is the only required option.

Options Hash (options):

  • :count (Object) —

    How many instances to request. By default one instance is requested. You can specify this either as an integer or as a Range, to indicate the minimum and maximum number of instances to run. Note that for a new account you can request at most 20 instances at once.

  • :block_device_mappings (Hash) —

    This must be a hash; the keys are device names to map, and the value for each entry determines how that device is mapped. Valid values include:

    • A string, which is interpreted as a virtual device name.

    • The symbol :no_device, which overrides the default mapping for a device so that it is not mapped to anything.

    • A hash with any of the following options. One of :snapshot, :snapshot_id or :volume_size is required.

      :snapshot

      A snapshot to use when creating the block device.

      :snapshot_id

      The ID of a snapshot to use when creating the block device.

      :volume_size

      The size of volume to create, in gigabytes.

      :delete_on_termination

      Setting this to true causes EC2 to delete the volume when the instance is terminated.

  • :monitoring (Boolean) —

    Setting this to true enables CloudWatch monitoring on the instances once they are started.

  • :availability_zone (String) —

    Specifies the availability zone where the instance should run. Without this option, EC2 will choose an availability zone for you.

  • :image_id (String) —

    ID of the AMI you want to launch.

  • :key_name (String) —

    The name of the key pair to use. Note: Launching public images without a key pair ID will leave them inaccessible.

  • :security_groups (Array) —

    The names of the security groups that will be used to determine network access rules for the instances. You may pass instances of SecurityGroup as well.

  • :user_data (String) —

    Arbitrary user data. You do not need to encode this value.

  • :instance_type (String) —

    The type of instance to launch, for example “m1.small”.

  • :kernel_id (String) —

    The ID of the kernel with which to launch the instance.

  • :ramdisk_id (String) —

    The ID of the RAM disk to select. Some kernels require additional drivers at launch. Check the kernel requirements for information on whether you need to specify a RAM disk. To find kernel requirements, refer to the Resource Center and search for the kernel ID.

  • :disable_api_termination (Boolean) —

    Specifies whether you can terminate the instance using the EC2 API. A value of true means you can’t terminate the instance using the API (i.e., the instance is “locked”); a value of false means you can. If you set this to true, and you later want to terminate the instance, you must first enable API termination. For example:

    i = ec2.instances.create(:image_id => "ami-8c1fece5",
                         :disable_api_termination => true)
i.api_termination_disabled?        # => true
i.terminate                        # raises an exception
i.api_termination_disabled = false
i.terminate                        # terminates the instance
  • :instance_initiated_shutdown_behavior (String) —

    Determines whether the instance stops or terminates on instance-initiated shutdown.

Returns:

  • (Instance or Array) —

    If a single instance is being created, this returns an AWS::EC2::Instance to represent the newly created instance. Otherwise it returns an array of instance objects.



171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
 
# File 'lib/aws/ec2/instance_collection.rb', line 171

def create options = {}

  if image = options.delete(:image)
    options[:image_id] = image.id
  end

  if kernel = options.delete(:kernel)
    options[:kernel_id] = kernel.id
  end

  if ramdisk = options.delete(:ramdisk)
    options[:ramdisk_id] = ramdisk.id
  end

  if key_pair = options.delete(:key_pair)
    options[:key_name] = key_pair.name
  end

  options = count_options(options).merge(options)
  options.delete(:count)

  options[:user_data] = Base64.encode64(options[:user_data]).strip if
    options[:user_data]

  options[:block_device_mappings] =
    translate_block_device_mappings(options[:block_device_mappings]) if
    options[:block_device_mappings]

  options[:monitoring] = { :enabled => true } if
    options[:monitoring_enabled]
  options.delete(:monitoring_enabled)

  options[:placement] = {
    :availability_zone => options[:availability_zone].to_s
  } if options[:availability_zone]
  options.delete(:availability_zone)

  options[:security_groups] = group_opts(options[:security_groups]) if
    options[:security_groups]

  options[:client_token] = UUIDTools::UUID.timestamp_create.to_s

  resp = client.run_instances(options)

  if options[:min_count] == options[:max_count] and
      options[:min_count] == 1
    self[resp.instances_set.first.instance_id]
  else
    resp.instances_set.map do |i|
      self[i.instance_id]
    end
  end
end

#each {|Instance| ... } ⇒ Object

Yields:

  • (Instance) —

    Yields each instance in the collection.



228
229
230
231
232
233
234
235
 
# File 'lib/aws/ec2/instance_collection.rb', line 228

def each(&block)
  response = filtered_request(:describe_instances)
  response.reservation_set.each do |r|
    r.instances_set.each do |i|
      yield(Instance.new(i.instance_id, :config => config))
    end
  end
end