sparkline showing the number of lines in a file

gistfile1.txt

#!/usr/bin/ruby

# sparkline showing the number of lines in a file
# run from cron at regular intervals

require 'rubygems'
require 'sparklines'

file_to_count = '/tmp/growing_file'
count_file = "#{file_to_count}.linecount"
graph = '/tmp/growing_file.png'

open(count_file, 'a') do |cf|
  open(file_to_count) { |ftc| cf.write("#{ftc.readlines.size}\n") }
end

open(count_file) do |f|
  data = f.readlines.map { |li| li.to_i }
  Sparklines.plot_to_file(graph, data, :line_color => :red)
end