Crystal-Lang example using http/client, logger and option_parser

site_checker.cr

require "http/client"
require "option_parser"
require "logger"

destination = "changeme"
help = ""

log = Logger.new(STDOUT)
log.level = Logger::INFO

OptionParser.parse! do |parser|
  parser.banner = "Usage: #{PROGRAM_NAME} (-d NAME | --destination=NAME)"
  parser.on("-d NAME", "--destination=NAME", "Defines endpoint to inspect (prod-1 or prod-2)") { |name| destination = name}
  parser.on("-h", "--help", "Show this help") { puts parser }
end

if destination == "changeme"
  log.error("Please supply a valid endpoint to test!")
  exit 1
end

resp = HTTP::Client.get "http://#{destination}.example.io/api/master"
if resp.status_code == 200 && resp.body == "true"
  log.info("Yes, #{destination} is master")
  exit 0
else
  log.warn("No, #{destination} is NOT master")
  exit 1
end