Module: Enscalator::Helpers

Includes:
Dns, Stack, Wrappers
Included in:
EnAppTemplateDSL, Plugins::ElasticBeanstalk, Plugins::Elasticache, RichTemplateDSL
Defined in:
lib/enscalator/helpers.rb,
lib/enscalator/helpers/dns.rb,
lib/enscalator/helpers/stack.rb,
lib/enscalator/helpers/wrappers.rb,
lib/enscalator/helpers/sub_process.rb

Overview

Collection of helper classes and static methods

Defined Under Namespace

Modules: Dns, Stack, Wrappers Classes: SubProcess

Instance Method Summary collapse

Methods included from Dns

#get_dns_records, #upsert_dns_record

Methods included from Stack

#cfn_create_stack, #generate_parameters, #get_resource, #get_resources, #wait_stack

Methods included from Wrappers

#cfn_client, #cfn_resource, #ec2_client, #route53_client

Instance Method Details

#cfn_call_script(region, dependent_stack_name, script_path, keys, prepend_args: '', append_args: '') ⇒ Object

Deprecated.

this method is no longer used

Call script

Parameters:

  • region (String) —

    AWS region identifier

  • dependent_stack_name (String) —

    name of the stack current stack depends on

  • script_path (String) —

    path to script

  • keys (Array) —

    list of keys

  • prepend_args (String) (defaults to: '') —

    prepend arguments

  • append_args (String) (defaults to: '') —

    append arguments



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# File 'lib/enscalator/helpers/sub_process.rb', line 40

def cfn_call_script(region,
                    dependent_stack_name,
                    script_path,
                    keys,
                    prepend_args: '',
                    append_args: '')
  cfn = cfn_resource(cfn_client(region))
  stack = wait_stack(cfn, dependent_stack_name)
  args = get_resources(stack, keys).join(' ')
  cmd = [script_path, prepend_args, args, append_args]
  begin
    run_cmd(cmd)
  rescue Errno::ENOENT
    puts $ERROR_INFO.to_s
    STDERR.puts cmd
  end
end

#create_ssh_key(key_name, region, force_create: false) ⇒ Object

Create ssh public/private key pair, save private key for current user

Parameters:

  • key_name (String) —

    key name

  • region (String) —

    aws region

  • force_create (Boolean) (defaults to: false) —

    force to create a new ssh key



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# File 'lib/enscalator/helpers.rb', line 62

def create_ssh_key(key_name, region, force_create: false)
  # Ignoring attempts to generate new ssh key when not deploying
  if @options && @options[:expand]
    warn '[Warning] SSH key can be generated only for create or update stack actions'
    return
  end

  client = ec2_client(region)
  aws_profile = if Aws.config.key?(:credentials)
                  creds = Aws.config[:credentials]
                  creds.profile_name if creds.respond_to?(:profile_name)
                end
  target_dir = File.join(Enscalator::ASSETS_DIR, aws_profile ? aws_profile : 'default')
  FileUtils.mkdir_p(target_dir) unless Dir.exist? target_dir
  if !client.describe_key_pairs.key_pairs.collect(&:key_name).include?(key_name) || force_create
    # delete existed ssh key
    client.delete_key_pair(key_name: key_name)

    # create a new ssh key
    key_pair = client.create_key_pair(key_name: key_name)
    STDERR.puts "Created new ssh key with fingerprint: #{key_pair.key_fingerprint}"

    # save private key for current user
    private_key = File.join(target_dir, key_name)
    File.open(private_key, 'w') do |wfile|
      wfile.write(key_pair.key_material)
    end
    STDERR.puts "Saved created key to: #{private_key}"
    File.chmod(0600, private_key)
  else
    key_fingerprint =
      begin
        Aws::EC2::KeyPair.new(key_name, client: client).key_fingerprint
      rescue NotImplementedError
        # TODO: after upgrade of aws-sdk use only Aws::EC2::KeyPairInfo
        Aws::EC2::KeyPairInfo.new(key_name, client: client).key_fingerprint
      end
    STDERR.puts "Found existing ssh key with fingerprint: #{key_fingerprint}"
  end
end

#find_ami(client, owners: ['self'], filters: nil) ⇒ Hash

Find ami images registered

Parameters:

  • client (Aws::EC2::Client) —

    instance of AWS EC2 client

Returns:

  • (Hash) —

    images satisfying query conditions

Raises:

  • (ArgumentError) —

    when client is not provided or its not expected class type



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# File 'lib/enscalator/helpers.rb', line 39

def find_ami(client, owners: ['self'], filters: nil)
  fail ArgumentError, 'must be instance of Aws::EC2::Client' unless client.instance_of?(Aws::EC2::Client)
  query = {}
  query[:dry_run] = false
  query[:owners] = owners if owners.is_a?(Array) && owners.any?
  query[:filters] = filters if filters.is_a?(Array) && filters.any?
  client.describe_images(query)
end

#flatten_hash(input) ⇒ Object

Convert hash with nested values to flat hash

Parameters:

  • input (Hash) —

    that should be flatten



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# File 'lib/enscalator/helpers.rb', line 115

def flatten_hash(input)
  input.each_with_object({}) do |(k, v), h|
    if v.is_a?(Hash)
      flatten_hash(v).map do |h_k, h_v|
        h["#{k}.#{h_k}".to_sym] = h_v
      end
    else
      h[k] = v
    end
  end
end

#gen_ssh_key_name(app_name, region, stack_name) ⇒ Object

Generate ssh keyname from app_name, region and stack name

Parameters:

  • app_name (String) —

    application name

  • region (String) —

    aws region

  • stack_name (String) —

    cloudformation stack name



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# File 'lib/enscalator/helpers.rb', line 53

def gen_ssh_key_name(app_name, region, stack_name)
  [app_name, region, stack_name].map(&:underscore).join('_')
end

#init_assets_dir ⇒ String

Initialize enscalator directory

Returns:

  • (String) 


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# File 'lib/enscalator/helpers.rb', line 19

def init_assets_dir
  FileUtils.mkdir_p(Enscalator::ASSETS_DIR) unless Dir.exist?(Enscalator::ASSETS_DIR)
end

#init_aws_config(region, profile_name: nil) ⇒ Object

Provision Aws.config with custom settings

Parameters:

  • region (String) —

    valid aws region

  • profile_name (String) (defaults to: nil) —

    aws credentials profile name



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# File 'lib/enscalator/helpers.rb', line 26

def init_aws_config(region, profile_name: nil)
  fail ArgumentError, 'Unable to proceed without region' if region.blank?
  opts = {}
  opts[:region] = region
  opts[:credentials] = Aws::SharedCredentials.new(profile_name: profile_name) unless profile_name.blank?
  Aws.config.update(opts)
end

#read_user_data(app_name) ⇒ Object

Read user data from file

Parameters:

  • app_name (String) —

    application name



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# File 'lib/enscalator/helpers.rb', line 106

def read_user_data(app_name)
  user_data_path = File.join(File.expand_path('..', __FILE__), 'plugins', 'user-data', app_name)
  fail("User data path #{user_data_path} not exists") unless File.exist?(user_data_path)
  File.read(user_data_path)
end

#run_cmd(cmd) ⇒ String

Run command and print captured output to corresponding standard streams

Parameters:

  • cmd (Array) —

    command array to be executed

Returns:

  • (String) —

    produced output from executed command



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# File 'lib/enscalator/helpers/sub_process.rb', line 62

def run_cmd(cmd)
  # use contracts to get rid of exceptions: https://github.com/egonSchiele/contracts.ruby
  fail ArgumentError, "Expected Array, but actually was given #{cmd.class}" unless cmd.is_a?(Array)
  fail ArgumentError, 'Argument cannot be empty' if cmd.empty?
  SubProcess.new(cmd.join(' ')) do |stdout, stderr, _thread|
    STDOUT.puts stdout if stdout
    STDERR.puts stderr if stderr
  end
end