From: tamouse mailing lists <tamouse.lists@...>
Date: 2013-02-10T08:51:09+09:00
Subject: Re: New to ruby - need assistance with rewriting a script

On Fri, Feb 8, 2013 at 9:00 AM, Ronald Craft <lists@ruby-forum.com> wrote:
> Hello,
>
> I'm working on learning ruby and trying to figure out how I would take
> an existing example and rewrite it in a way that suits my own usage.
> What I'm looking for here isn't for someone to just give me a block of
> fixed code and be like, "Oh, here you go!" since I won't actually learn
> anything from that.
>
> So, here's the script:
>
> ####
> require 'rubygems'
> require 'crontab-parser'
>
> start_time = Time.parse(ARGV[0])
> end_time   = Time.parse(ARGV[1])
>
> them
> cron_data = File.readlines(ARGV[2]).select {|line| line =~ /^[0-9*]/}
> cron  = CrontabParser.new(cron_data.join("\n"))
> (start_time..end_time).each do |timestamp|
>   next unless timestamp.sec.to_i == 0
>   cron.each do |cron_entry|
>     if cron_entry.should_run?(timestamp)
>       puts "#{timestamp}\t#{cron_entry.cmd}"
>     end
>   end
> end
> ####
>
> Again, not my code. What I want to do is like so:
>
> 1. Run this script without requiring any CLI arguments. I know the time
> interval I want to search for (between 1 and 14 minutes) but I don't
> want to have to type out the range of times when I execute the script.
> I've seen the chronic gem and believe this is the answer I'm looking
> for, but not certain of how I'd integrate that in here.
>
> 2. Scan all of the files in a directory with the exception of two (of
> which I'd need to set an .excludes). Something like this (my code):
>
> ####
> Dir["/var/spool/cron/*"].each do |file|
>   username = file.split("/").last
>   crontab = CrontabParser.new(File.read(file))
>
>   crontab.each do |cron|
>     puts "User: #{username}"
>     # Do whatever
>   end
> end
> ####
>
> This way I can get the output of:
>
> User1
> cron1
> cron2
>
> User2
> Cron1
> Cron2
>
> And so on.
>
> Can anyone offer some sort of assistance in helping me get this to where
> I want it? I'm happy with any kind of relevant documentation for this
> task (there's so much unrelated documentation that I end up
> lost/confused), examples that are similar in what I'm trying to do, or
> partial
> answers that will point me in the right direction.
>
> I know this may seem a bit unorthodox, but it's how I learn - I can't
> just read a book on ruby and understand how to do everything (I've read
> Chis Pine's book and it has helped a little, but not enough for me to be
> able to do something like this on my own).
>
> Thanks in advance!
>
> --
> Posted via http://www.ruby-forum.com/.
>

You might want to look at TImeCop in association with Chronic.