Ruby AWS client example

.tool-versions

ruby 3.3.0

Gemfile

source "https://rubygems.org"

gem 'aws-sdk-ec2', '~> 1'
gem 'aws-sdk-autoscaling', '~> 1'
gem 'base64'
gem 'nokogiri'
gem 'terminal-table'

main.rb

#!/usr/bin/env ruby

require 'aws-sdk-autoscaling'
require 'aws-sdk-ec2'
require 'terminal-table'

auto_scaling_groups = []

cluster_id = "example-cluster"

get_launch_key = ->(g) {[g.launch_configuration_name, g.launch_template&.launch_template_name, g.launch_template&.version].compact.map(&:to_s).join(';')}

asg_client = Aws::AutoScaling::Client.new
ec2_client = Aws::EC2::Client.new
# 

asg_client.describe_auto_scaling_groups({filters: [{name: "tag:k8s.io/cluster/#{cluster_id}", values: ["owned"]}]}).each do |resp|
    auto_scaling_groups += resp.auto_scaling_groups.map do |asg| 
        asg_result = {
            auto_scaling_group_name: asg.auto_scaling_group_name,
        }

        launch_key = get_launch_key.call(asg)
        asg_result[:launch_key] = launch_key

        asg_result[:instance_ids] = asg.instances.map(&:instance_id)

        instances_by_launch_key = { "#{launch_key}" => 0 }
        asg.instances.each do |i|
            lki = get_launch_key.call(i)
            if !instances_by_launch_key[lki]
                instances_by_launch_key[lki] = 1
            else
                instances_by_launch_key[lki] += 1
            end
        end

        asg_result[:outliers_count] = 0
        instances_by_launch_key.keys.reject { |key| key == asg_result[:launch_key] }.each do |key|
            asg_result[:outliers_count] += instances_by_launch_key[key]
        end

        asg_result[:instances_by_launch_key] = instances_by_launch_key
        asg_result[:desired] = asg.desired_capacity
        asg_result[:max]     = asg.max_size
        asg_result[:autoscaler_tag] = asg.tags.select {|t| t.key == "k8s.io/cluster-autoscaler/enabled" }.fetch(0, {value: "false"})[:value] == "true"
        asg_result
    end
end


asg_rows = auto_scaling_groups.map do |asg| 
            [
                asg[:auto_scaling_group_name],
                asg[:launch_key],
                asg[:instances_by_launch_key].keys.map {|key| "#{key}=#{asg[:instances_by_launch_key][key]}"}.join('\n'),
                "#{asg[:desired]}/#{asg[:max]}",
                asg[:autoscaler_tag],
                asg[:outliers_count]
            ]
        end


asg_table = Terminal::Table.new :title => "Auto Scaling Groups",
            :headings => ['Name', 'Current launch conf/template', 'Instances by launch conf/template', 'Desired/Max', 'Autoscaler tag', 'Outliers count'],
            :rows => asg_rows



# puts(auto_scaling_groups)
puts(asg_table)



auto_scaling_groups.each do |asg|
    if asg[:instance_ids].empty?
        puts "#{asg[:auto_scaling_group_name]} has no instances. Skipping..."
        next
    end
    full_instances = []
    ec2_client.describe_instances({instance_ids: asg[:instance_ids]}).each do |resp|
        full_instances += resp.reservations.map {|rsv| rsv.instances }.flatten.map do |inst|
            instance_result = {
                instance_id: inst.instance_id,
                status: inst.state.name,
                image_id: inst.image_id,
                private_dns_name: inst.private_dns_name
            }
        end
    end

    instance_rows = full_instances.map do |inst|
        [
            inst[:instance_id],
            inst[:status],
            inst[:image_id],
            inst[:private_dns_name]
        ]
    end

    instance_table = Terminal::Table.new :title => "Instances of #{asg[:auto_scaling_group_name]}",
                        :headings => ['ID', 'Status', 'Image', 'Private DNS name'],
                        :rows => instance_rows

    puts(instance_table)



end





# puts
# puts(resp.to_h)

# Columns:
# 


# https://docs.aws.amazon.com/sdk-for-ruby/v3/api/Aws/PageableResponse.html
# https://docs.aws.amazon.com/sdk-for-ruby/v3/api/Aws/AutoScaling/Client.html#describe_auto_scaling_groups-instance_method
# https://github.com/tj/terminal-table

# while response.next_page? do
#   response = response.next_page
#   # Use the response data here...
# end