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Ever need to watch a specific content page on a Web site for changes? Maybe it's a storefront that needs rebooting, or your homepage that you want to ensure doesn't change without your knowledge. The Web Watch Daemon is a very simple perl script that monitors any page on the Web for a specific content string (the keyphrase). If it finds that keyphrase missing from the page, then it will: (1) send an alert to an email address you specify and/or (2) log the date and time of the failure.


  • Download webwatch.pl now (version 1.0)
    (Change the '.txt' extension to '.pl' after the download to run)
Requires the LWP and HTTP perl modules (find them here).

Change the variables at the top of the script as noted in the inline instructions, especially the watch_url and keyphrase.

Run this on a server that has Internet connectivity as a cron job, every X minutes you want to check on your server. Sample crontab line:

 05 * * * * perl /home/user/johnsmith/webwatch.pl
This line would run the script every hour at :05. If your watch page is very important to your site, you might run it every minute or every 5 minutes.

Please note: You can run this script on your Web server. But for more robust applications, you should consider running it on a Web server external to your network. This allows the script to test not only for content changes in the target page, but also network connectivity.


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