require 'optparse'
require 'net/http'
require 'aws-sdk-resources'

# bundle exec ruby cloudwatch_put_process.rb --process nginx
opts = ARGV.getopts('', 'process:')
process = opts['process']

METADATA_ENDPOINT = 'http://169.254.169.254/latest/meta-data'
instance_id = Net::HTTP.get(URI.parse("#{METADATA_ENDPOINT}/instance-id"))

process_count = `ps awux | grep -w #{process} | grep -v grep | grep -v "cloudwatch_put_process.rb --process" | wc -l`

cloudwatch = Aws::CloudWatch::Client.new(region: 'ap-northeast-1')
cloudwatch.put_metric_data(
  namespace: 'Custom Metrix',
  metric_data: [
    {
      metric_name: "#{process}Processes",
      dimensions: [
        {
          name: 'InstanceId',
          value: instance_id,
        }
      ],
      value: process_count,
      unit: 'Count',
    }
  ]
)