Current time in location of IP address.

gistfile1.rb

#!/usr/bin/env ruby

require 'geoip'
require 'tzinfo'

geoip = GeoIP.new('GeoLiteCity.dat')

location = geoip.city ARGV[0]
if location.nil?
  puts Time.now.utc.to_datetime.iso8601
  exit 100
end

tz = TZInfo::Timezone.get location.timezone
offset = tz.current_period.utc_total_offset
absoff = offset.abs / 60

pn = (offset < 0 ? '-' : '+')
hoff = absoff / 60
moff = absoff % 60

ctime = tz.current_time_and_period.first

puts DateTime.new(ctime.year, ctime.month, ctime.day, ctime.hour, ctime.min, ctime.sec, "#{pn}#{hoff}:#{moff}").iso8601