Come along and see how to create a plugin that can monitor your website. You'll need: your computer with perl and cpan installed (preferably with Nagios::Plugin::WWW::Mechanize already installed), your web site (remotely accessible from your computer), your credentials to authenticate and your success criteria. Basic perl knowledge assumed. Advanced perl knowledge provided!

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How to create a web transaction plugin
in Perl using
Nagios::Plugin::WWW::Mechanize
Ton Voon, Opsera
Nürnberg
October 2009
Licenced under Creative Commons Attribution-Non-Commercial-Share Alike 2.0

2. © Opsera 2009 Commercial in Confidence
Agenda
! My turn
• Explanation and theory
• Example
! Your turn! You need:
• Your computer with perl and cpan installed
• Your web site, accessible from your computer
• Your credentials to login to your site
• Your success criteria
! Interlude to perl’s debugger
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CPAN
(Comprehensive Perl Archive Network)

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Nagios::Plugin

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WWW::Mechanize

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Nagios::Plugin::
WWW::Mechanize

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check_opsview_mailing_list

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Process
! Install Nagios::Plugin::WWW::Mechanize
• cpan Nagios::Plugin::WWW::Mechanize
! Work out how your web page works:
• URL
• form name
• field names
! Write your plugin!
! chmod u+x check_my_site
! ./check_my_site
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Your turn

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perl -d (debugger)

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Perl debugger cheat sheet
! perl -d {script} - start!
! l - list script from current position
! n - next command
! b {line number} - add a break point at line number
! c - continue until a break point
! $a = “new value” - change $a
! x $a - print contents of $a
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