kobtea/aws_ro

"Ruby Object" or "ReadOnly wrapper" of AWS SDK for Ruby

AwsRo

Wrapper class of AWS Resource objects to enable to access properties more easily, more ruby-likely.

The targets of this library are small and medium scale AWS systems.

Now supported only Aws::EC2 and Aws::ElasticLoadBalancing.

Installation

Add this line to your application's Gemfile:

gem 'aws_ro', '~> 1.1'

And then execute:

$ bundle

Purpose of this gem

Easy access to AWS Resources.

For example, I'd like to print values of 'MyTag' tag of instances which also contains 'MyEnv'=='develop' tag.

By using plain AWS SDK v2:

client = Aws::EC2::Client.new(some_options)
res = client.describe_instances(filters: [{name: 'tag:MyEnv', values: ['develop']}, {name: 'tag:MyTag', values: ['*']}])
instances = res.reservations.flat_map(&:instances)
instances.each do |i|
  v = i.tags.find { |t| t.key == 'MyTag' }.value
  puts "ID: #{i.instance_id}, MyTag value: #{v}"
end

This is not difficult, but is a little boring.

On the other hand, by using the aws_ro gem:

repo = AwsRo::EC2::Repository.new(some_options)
repo.tags({'MyEnv' => 'develop', 'MyTag' => '*'}).each do |i|
  puts "ID: #{i.instance_id}, MyTag value: #{i.my_tag}"
end

This is simplified and keeping readability.

Usage

Basic Usage

ec2_options = { region: 'ap-northeast-1' }
repo = AwsRo::EC2::Repository.new(ec2_options)
instances = repo.running.tags({'MyAttrName' => 'MyValue'})
instances.each do |i|
  puts "#{i.name} #{i.public_ip_address}, #{i.my_attr_name}"
end

Classes

class : AwsRo::EC2::Repository

Repository is wrapper of EC2 client. It supports chainable queries to describe instances.

Initialize

# initialize with Aws::EC2::Client
client.class
# => Aws::EC2::Client
repo = AwsRo::EC2::Repository.new(client)

# initialize with option hash
repo = AwsRo::EC2::Repository.new({ region: 'ap-northeast-1' })

accessor

# get raw client
repo.client
# => Aws::EC2::Client

query methods

# all running instance
repo.running.all? do |i|
  i.class
  # => AwsRo::EC2::Instance
  i.state.name == 'running'
end
# => true

# All query methods are chainable and return an `Array` like object.
## list security group of running-public-instances
repo.running.filters([{name: 'ip-address', values: ['*'] }]).each do |i|
  puts i.ec2.security_groups.map(&:group_name)
end

## list my 'InUse' tag instances
repo.not_terminated.tags('InUse' => '*').map(&:instance_id)
# => ["i-xxxxxxxx","i-yyyyyyyy","i-zzzzzzzz", ...]

class : AwsRo::EC2::Instance

Instance is wrapper of EC2 instace object.

ins = repo.all.first

static accessors

# get raw ec2 object
ins.ec2
# => Aws::EC2::Instance

# some delegated methods and aliases for accessibility
[
  ins.instance_id == ins.ec2.instance_id,
  ins.public_ip_address == ins.ec2.public_ip_address && ins.public_ip_address == ins.public_ip,
  ins.private_ip_address == ins.ec2.private_ip_address && ins.private_ip == ins.private_ip,
  ins.key_name == ins.ec2.key_name,
  ins.state == ins.ec2.state
].all?
# => true

dynamic tag accessors

# Instance#tags returns `Struct` of tags.
ins.tags.Name
# => 'Value of Name tag'
ins.tags.roles
# => 'staging, somerole'
ins.tags.xyz_enabled
# => 'True'

## and dynamically-defined reader methods are available as snake_case-ed tag name.
## their values are stripped and formatted as `Array` if the value include whitespaces,
## as boolean if the value like  boolean and when use `?`-terminated method.
ins.name
# => 'Value of Name tag'
ins.roles
# => ['staging', 'somerole']
ins.xyz_enabled?
# => true

Development

After checking out the repo, run bin/setup to install dependencies. Then, run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release to create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

1. Fork it ( https://github.com/gree/aws_ro/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

License

This library is distributed under the Apache License, version 2.0