Class: CloudMaker::EC2

Inherits:
Object
  • Object
show all
Defined in:
lib/cloud_maker/ec2.rb

Constant Summary collapse

CLOUD_MAKER_CONFIG =

Public: A CloudMaker::Config hash that describes the config properties EC2 relies on.

{
  'cloud-maker' => {
    'ami' => {
      'required' => true,
      'description' => "The Amazon AMI ID for the instance."
    },
    'instance_type' => {
      'required' => true,
      'description' => "The Amazon instance type, eg. m1.small."
    },
    'availability_zone' => {
      'required' => true,
      'description' => "The Amazon availability zone, eg. us-east-1a"
    },
    'key_pair' => {
      'default' => "",
      'description' => "The name of an Amazon key pair, so you can actually login to the instance."
    },
    'elastic_ip' => {
      'default' => '',
      'description' => "An elastic IP address you control that you would like to associate to the instance."
    },
    'security_group' => {
      'default' => 'default',
      'required' => true,
      'description' => 'The Amazon EC2 security group to launch the instance with.'
    },
    'iam_role' => {
      'default' => '',
      'description' => 'The IAM instance profile name or ARN you would like to use.'
    },
    'cname' => {
      'default' => '',
      'description' => "A dns entry you would like to CNAME to this instance."
    }
  }
}
BUCKET_TAG =

Public: The name of the tag that will be used to find the name of an s3 bucket for archiving/information retrieval

's3_archive_bucket'

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options) ⇒ EC2

Public: Creates a new EC2 instance

cloud_maker_config - A CloudMaker::Config object describing the instance

to be managed.

options - S3 configuration options

:aws_access_key_id     - (required) The AWS access key
:aws_secret_access_key - (required) The AWS secret

Returns a new CloudMaker::EC2 instance Raises RuntimeError if any of the required options are not specified



62
63
64
65
66
67
68
69
70
71
72
 
# File 'lib/cloud_maker/ec2.rb', line 62

def initialize(options)
  required_keys = [:aws_access_key_id, :aws_secret_access_key]
  unless (required_keys - options.keys).empty?
    raise RuntimeError.new("Instantiated #{self.class} without required attributes: #{required_keys - options.keys}.")
  end

  self.aws_access_key_id = options[:aws_access_key_id]
  self.aws_secret_access_key = options[:aws_secret_access_key]

  self.ec2 = AWS::EC2.new(:access_key_id => self.aws_access_key_id, :secret_access_key => self.aws_secret_access_key)
end

Instance Attribute Details

#aws_access_key_id ⇒ Object

Public: Gets/Sets the AWS secret.



6
7
8
 
# File 'lib/cloud_maker/ec2.rb', line 6

def aws_access_key_id
  @aws_access_key_id
end

#aws_secret_access_key ⇒ Object

Public: Gets/Sets the AWS access key.



4
5
6
 
# File 'lib/cloud_maker/ec2.rb', line 4

def aws_secret_access_key
  @aws_secret_access_key
end

#ec2 ⇒ Object

Internal: Gets/Sets the AWS::EC2 instance.



8
9
10
 
# File 'lib/cloud_maker/ec2.rb', line 8

def ec2
  @ec2
end

Class Method Details

.instance_to_hash(instance) ⇒ Object

Public: Generates a hash of properties from an AWS::EC2 instance

Returns a hash of properties for the instance.



211
212
213
214
215
216
217
218
219
220
221
222
223
224
 
# File 'lib/cloud_maker/ec2.rb', line 211

def instance_to_hash(instance)
  {
    :instance_id => instance.id,
    :ami => instance.image_id,
    :api_termination_disabled => instance.api_termination_disabled?,
    :dns_name => instance.dns_name,
    :ip_address => instance.ip_address,
    :private_ip_address => instance.private_ip_address,
    :key_name => instance.key_name,
    :owner_id => instance.owner_id,
    :status => instance.status,
    :tags => instance.tags.inject({}) {|hash, tag| hash[tag.first] = tag.last;hash}
  }
end

Instance Method Details

#find_instance(instance_id) ⇒ Object

Internal: Find the instance object for an instance ID regardless of what region the instance is in. It looks in the default region (us-east-1) first and then looks in all regions if it’s not there.

Returns nil or an AWS::EC2::Instance



176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
 
# File 'lib/cloud_maker/ec2.rb', line 176

def find_instance(instance_id)
  # Check the default region first
  return ec2.instances[instance_id] if ec2.instances[instance_id].exists?

  # If we don't find it there look in every region
  instance = nil
  ec2.regions.each do |region|
    if region.instances[instance_id].exists?
      instance = region.instances[instance_id]
      break
    end
  end

  instance
end

#find_region(availability_zone) ⇒ Object

Internal: Find the region object for a given availability zone. Currently works based on amazon naming conventions and will break if they change.

Returns an AWS::EC2::Region Raises a RuntimeError if the region doesn’t exist



198
199
200
201
202
203
204
205
 
# File 'lib/cloud_maker/ec2.rb', line 198

def find_region(availability_zone)
  region_name = availability_zone.gsub(/(\d)\w$/, '\1')
  if ec2.regions[region_name].exists?
    ec2.regions[region_name]
  else
    raise RuntimeError.new("The region #{region_name} doesn't exist - region name generated from availability_zone: #{availability_zone}.")
  end
end

#info(instance_id) ⇒ Object

Public: Fetch archived information about an instance

Returns a hash of information about the instance as it was launched



77
78
79
80
81
82
83
84
85
86
87
88
89
 
# File 'lib/cloud_maker/ec2.rb', line 77

def info(instance_id)
  instance = find_instance(instance_id)
  bucket = instance.tags[BUCKET_TAG]

  archiver = S3Archiver.new(
    :instance_id => instance_id,
    :aws_access_key_id => self.aws_access_key_id,
    :aws_secret_access_key => self.aws_secret_access_key,
    :bucket_name => bucket
  )

  archiver.load_archive
end

#launch(cloud_maker_config) ⇒ Object

Public: Launches a new EC2 instance, associates any specified elastic IPS with it, adds any specified tags, and archives the launch details to S3.

Returns an AWS::EC2 object for the launched instance.



102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
 
# File 'lib/cloud_maker/ec2.rb', line 102

def launch(cloud_maker_config)
  user_data = cloud_maker_config.to_user_data

  if !cloud_maker_config['availability_zone'].nil? && !cloud_maker_config['availability_zone'].empty?
    region = find_region(cloud_maker_config['availability_zone'])
  else
    region = ec2 # .instances.create will just put things in the default region
  end
  instance = region.instances.create(
    :image_id => cloud_maker_config['ami'],
    :iam_instance_profile => cloud_maker_config['iam_role'],
    :security_groups => cloud_maker_config['security_group'],
    :instance_type => cloud_maker_config['instance_type'],
    :key_name => cloud_maker_config['key_pair'],
    :availability_zone => cloud_maker_config['availability_zone'],
    :user_data => user_data
  )

  begin
    instance.tags.set(cloud_maker_config['tags']) if cloud_maker_config['tags']
  rescue AWS::EC2::Errors::InvalidInstanceID::NotFound => e
    retries ||= 0
    if retries < 5
      sleep(2**retries)
      retries += 1
      retry
    end
  end

  if cloud_maker_config.elastic_ip? || cloud_maker_config.cname?
    while instance.status == :pending
      #wait
    end
    instance.associate_elastic_ip(cloud_maker_config["elastic_ip"]) if cloud_maker_config.elastic_ip?

    if cloud_maker_config.cname?
      r53 = AWS::Route53::Client.new(:access_key_id => self.aws_access_key_id, :secret_access_key => self.aws_secret_access_key)

      zone = r53.list_hosted_zones[:hosted_zones].select {|zone|
        cloud_maker_config['cname'] + '.' =~ /#{Regexp.escape(zone[:name])}$/
      }.first

      r53.change_resource_record_sets(
        :hosted_zone_id => zone[:id],
        :change_batch => {
          :comment => "CloudMaker initialization of #{instance.instance_id}.", :changes => [{
            :action => "CREATE", :resource_record_set => {
              :name => cloud_maker_config['cname'],
              :type => 'CNAME',
              :ttl => 60,
              :resource_records => [{:value => instance.dns_name}]
            }
          }]
        }
      )
    end
  end

  archiver = S3Archiver.new(
    :instance_id => instance.id,
    :aws_access_key_id => self.aws_access_key_id,
    :aws_secret_access_key => self.aws_secret_access_key,
    :bucket_name => cloud_maker_config["tags"][BUCKET_TAG]
  )
  archiver.store_archive(cloud_maker_config, self.class.instance_to_hash(instance))

  instance
end

#terminate(instance_id) ⇒ Object

Public: Terminates the specified EC2 instance.

Returns nothing.



94
95
96
 
# File 'lib/cloud_maker/ec2.rb', line 94

def terminate(instance_id)
  find_instance(instance_id).terminate
end