Download RDS log

download_rds_log.rb

#!/usr/bin/env ruby
require 'rubygems'
require 'aws-sdk-core'
require 'pp'

Aws.config.update({
   :access_key_id     => ENV["AWS_ACCESS_KEY"],
   :secret_access_key => ENV["AWS_SECRET_KEY"],
   :region            => 'ap-northeast-1'
})

rds = Aws::RDS::Client.new

db_instance_identifier = 'myrds'

abort("Enter log filename.") if ARGV[0].nil?
rds_log_file = ARGV[0]
out_log_file = ARGV[0]

opts = {
  db_instance_identifier: db_instance_identifier,
  log_file_name: rds_log_file,
  number_of_lines: 100000000,
  marker: "0"
}

additional_data_pending = true
File.open(out_log_file, "wb+") do |file|
  while additional_data_pending do
    out = rds.download_db_log_file_portion(opts)
    puts out[:additional_data_pending]
    file.write(out[:log_file_data])

    additional_data_pending = (opts[:marker] != out[:marker])

    puts out[:marker]
    opts[:marker] = out[:marker]
    # additional_data_pending is not stable.
    #additional_data_pending = out[:additional_data_pending]
  end
end