Check MySQL Slave status from Shell using Ruby

check_slave_status.rb

#!/usr/bin/env ruby

@slave_status = Hash[%x(mysql -uroot -e 'SHOW SLAVE STATUS \\\G').split(/\s*\n\s*/).map { |e| spl = e.split(/\:\s*/); spl.size == 2 ? [spl.first, spl.last] : nil }.compact]

def slave_healthy?
  @slave_status['Slave_IO_Running'] == 'Yes' &&
  @slave_status['Slave_SQL_Running'] == 'Yes' &&
  @slave_status['Seconds_Behind_Master'] != 'NULL' &&
  @slave_status['Seconds_Behind_Master'].to_i < 1800
end

if slave_healthy?
  puts "Slave OK"
else
  puts "Slave ERROR: #{@slave_status}"
  abort
end