Scan a Wifi and log each new device connected on it

wifi_scanner.rb

require 'hooray'
require 'logger'

LOG_FILE = './wifi.log'.freeze
INTERVAL_TIME = 30
DEFAULT_NODE_NAME = 'UNKNOW'.freeze

class Scanner
  attr_reader :logger

  def initialize
    initialize_logger
    @old_seek = []
  end

  def scan
    @logger.debug('Start scan')
    new_seek = Hooray::Seek.new.nodes

    unless @old_seek.empty? # not log the first scan
      log_nodes (new_seek - @old_seek), 'connected'
      log_nodes (@old_seek - new_seek), 'left'
    end
    @old_seek = new_seek
  end

  private

  def log_nodes(nodes, verb)
    nodes.each do |node|
      name = node.name.nil? ? '' : "#{node.name}@"
      @logger.info "#{name}#{node.ip} #{verb}"
    end
  end

  def initialize_logger
    @logger = Logger.new(LOG_FILE)
    @logger.level = Logger::DEBUG
    @logger.datetime_format = '%Y-%m-%d %H:%M'
    @logger.formatter = proc do |severity, datetime, _progname, msg|
      datetime_formated = datetime.strftime('%Y-%m-%d %H:%M:%S')
      "#{datetime_formated} -- #{severity}: #{msg}\n"
    end
  end
end

scanner = Scanner.new
scanner.logger.debug('Start wifi_logger.rb')

begin
  loop do
    scanner.scan
    sleep INTERVAL_TIME
  end
rescue Interrupt => e
  scanner.logger.debug('Close wifi_logger.rb')
end

Usage, the ugly way

$ curl https://gist.githubusercontent.com/madeindjs/2df2d2bef7d6aaddd1bb6061975c54e1/raw/0fb6c340beff325f06e72675383f2f39c591af02/wifi_scanner.rb | ruby &

Make sure to install hooray before with gem install hooray