online_users.rb

#! /usr/bin/env ruby

require 'json'
require 'date'
require 'optparse'
require 'pp'
require 'net/http'

config_file = nil
debug = false

OptionParser.new do |opts|
  opts.on("-c", "--config-file CONFIG") do |d|
    config_file = d
  end
  opts.on("-D", "--debug") do |d|
    debug = true
  end
end.parse!

config      = JSON.parse(File.read(config_file))
unless ( %r(^/) =~ config['credentials_file'] ) then
  cred_file   = File.expand_path( "../#{config['credentials_file']}" , __FILE__ )
else
  cred_file   = config['credentials_file']
end

credentials = JSON.parse(File.read(cred_file))

def fetch_queues( host, port, username, password, vhost)
  http = Net::HTTP.new host, port
  req  = Net::HTTP::Get.new "/api/queues/#{vhost}?columns=name,idle_since"
  req.basic_auth username, password
  http.request(req).body
end

def parse_result(input, idle_minutes=10)
  cutoff_time  = DateTime.now() - Rational(( idle_minutes * 60.0)/86400 )
  counter = Hash.new(0)
  result = JSON.parse(input)
  result.each do |queue|
    idle_since = 
    if ( 
      queue['name'] =~ /^online/ and 
      ( queue['idle_since'].nil? or ( DateTime.parse(queue['idle_since']) > cutoff_time ) ) 
    ) 
      counter[queue['name']] += 1 
    end
  end
  counter.length
end

def send_event ( message, carbon_server, carbon_port, debug=false )
  require 'socket'
  if debug then
    puts message
  else
    s = TCPSocket.new carbon_server, carbon_port
    s.puts message
    s.close
  end
end

message = Array.new()

config['rabbitapi'].each do |api| 
  host = api['host']
  port = api['port']
  idle_minutes = api['idle_minutes']
  user = credentials[api['name']].split(':')[0]
  pass = credentials[api['name']].split(':')[1]

  api['envs'].each do |env|
    vhost = "frontend-#{env}"
    key         = "zensey.#{env}.users.online.#{idle_minutes}m"
    #p host, port, user, pass, vhost
    queues_result  = fetch_queues host, port, user, pass, vhost
    metric = parse_result(queues_result, idle_minutes)
    message << sprintf("%s %s %d\n", key, metric, Time.new().to_i)
  end
end

send_event message, config['carbon_server'], config['carbon_port'], debug