submit_metrics.rb

#!/usr/bin/env ruby

require 'cgi'
require 'uri'
require 'net/http'
require 'net/https'

USER = ARGV[0]
TOKEN = ARGV[1]
REGEX = ENV['REGEX'] ? Regexp.new(ENV['REGEX']) : /^(\S+)\s+(\S+)$/


def submit_gauges(values)
  url = URI.parse('https://metrics-api.librato.com/v1/metrics.json')

  http = Net::HTTP.new(url.host, url.port)
  if url.scheme == 'https'
    require 'net/https'
    http.use_ssl = true
  end

  req = Net::HTTP::Post.new(url.path)
  req.basic_auth USER, TOKEN 
  data = prepare_gauges(values)
  req.set_form_data(data)
  
  http.start do |http|
    res = http.request(req)
    
    case res
    when Net::HTTPSuccess, Net::HTTPOK
    else
      res.error!
    end
  end
end

def prepare_gauges(values)
  result = {}
  
  values.each_with_index do |(key, value), idx|
    if key_prefix = ENV['KEY_PREFIX']
      key = "#{key_prefix}#{key}"
    end

    result["gauges[#{idx}][name]"] = key
    result["gauges[#{idx}][value]"] = value
    
    if ENV['SOURCE']
      result["gauges[#{idx}][source]"] = ENV['SOURCE']
    end
    
    if ENV['PERIOD']
      now = Time.now
      now = now - (now.to_i % ENV['PERIOD'].to_i)
      result["gauges[#{idx}][measure_time]"] = now.to_i
    end
  end
  
  result
end


$stdin.each_line do |line|
  if line =~ REGEX
    submit_gauges($1 => $2)
  end
end