http://esola.co/posts/2016/horenso-introduction

reporter.rb

require 'net/http'
require 'uri'
require 'json'

resp = JSON.parse($stdin.gets)

if resp["exitCode"] != 0 then
  uri = URI.parse("https://hooks.slack.com/services/***")
  payload = {
    text: "```#{JSON.pretty_generate(resp)}```",
    channel: "@yyoshiki41",
    username: "Cron job fails",
    icon_emoji: ":scream_cat:"
  }
  Net::HTTP.post_form(uri, { payload: payload.to_json })
end