New Relic Ruby agent demo: set an error group callback used for noticed errors

reporter.rb

#!/usr/bin/env ruby
# frozen_string_literal: true

# INSTRUCTIONS:
#   - Place this file somewhere. It can be called something like `reporter.rb`
#
#   - Either place a newrelic.yml file in the same directory as this file OR
#     export the NEW_RELIC_LICENSE_KEY and NEW_RELIC_HOST environment variables.
#     If using a newrelic.yml file, it should look like this:
#       # newrelic.yml
#       development:
#         license_key: <YOUR KEY>
#         host: <YOUR ENVIRONMENT>-collector.newrelic.com
#
#   - Optionally update the ERROR_GROUP_NAMES constant below. At least 1 error
#     per group name will be created.
#
#   - Run this script with `ruby reporter.rb`
#     (or make it executable and use `./reporter.rb`)

require 'bundler/inline'

puts 'Checking out the Ruby agent with Bundler...'
gemfile do
  source 'https://rubygems.org'
  gem 'newrelic_rpm', git: 'https://github.com/newrelic/newrelic-ruby-agent',
                      branch: 'dev'
end

#
# ErrorReporter - A standalone error reporter demonstrator
#
class ErrorReporter
  ERROR_GROUP_NAMES = %w[MyCoolGroup MyTroublesomeGroup MyFamousGroup].freeze
  SHUTDOWN_SLEEP = 60
  LOG_FILE = 'log/newrelic_agent.log'

  def go
    wait_for_connection
    register_error_group_callback
    create_some_errors
    graceful_shutdown
    check_log
  end

  private

  def wait_for_connection
    puts 'Waiting for New Relic agent to connect...'
    puts "NOTE: If the connection process takes long, kill the script and check #{LOG_FILE} for WARN/ERROR"
    sleep 1 until NewRelic::Agent.agent.connected?
  end

  def register_error_group_callback
    puts 'Registering error group callback proc...'
    NewRelic::Agent.set_error_group_callback(callback_proc)
  end

  def callback_proc
    proc { |hash| Regexp.last_match(1) if hash[:error].message =~ /(#{ERROR_GROUP_NAMES.join('|')})/ }
  end

  def create_some_errors
    puts 'Creating some errors...'
    ERROR_GROUP_NAMES.each do |name|
      rand(1..5).times do
        error = StandardError.new("Here's a #{name} type error!")
        NewRelic::Agent.notice_error(error)
      end
    end
  end

  def graceful_shutdown
    puts "Giving the agent harvester time to send data up to the collector (sleep = #{SHUTDOWN_SLEEP} secs)..."
    sleep SHUTDOWN_SLEEP
    puts 'Shutting down New Relic agent...'
    NewRelic::Agent.shutdown
  end

  def check_log
    if log_data =~ %r{INFO : Reporting to: (https://.*?)(\s+|$)}
      puts "Data was submitted to #{Regexp.last_match(1)}"
    else
      puts "Couldn't glean a URL from the #{LOG_FILE} file. Check that file for WARN/ERROR"
    end
  end

  def log_data
    return File.read(LOG_FILE) if File.exist?(LOG_FILE)

    puts "The agent log file #{LOG_FILE} didn't appear to get created."
    ''
  end
end

ErrorReporter.new.go