#!/usr/bin/perl -w

use strict;
use LWP::Simple;

# file to store the update time 
my $speaker_prev_mod_time = '/home/qiang/bin/speaker_prev_mod';
# webpage to watch
my $speaker_url = 'http://cs.senecac.on.ca/speakers/speakersFlash.html
+';

# file to store the update time 
my $cherry_prev_mod_time = '/home/qiang/bin/cherrypick_prev_mod';
# another webpage to watch
my $cherry_url = 'http://cherryavenuefarms.org/';

# update is sent to this email box.
my $email = 'your@email.com';

# build the webpage hash
my %checks = ( 'seneca speaker series' => 
                { 'time_stamp' =>   $speaker_prev_mod_time,
                  'url_to_check' => $speaker_url 
                },
               'cherry picking opening' =>
                { 'time_stamp' =>   $cherry_prev_mod_time,
                  'url_to_check' => $cherry_url }
             );

foreach (my ($k,$v)=each %checks) {
    my $prev_mod_time = &get_prev($v->{time_stamp});
    my $cur_mod_time  = &get_current($v->{url_to_check});

    if ($cur_mod_time ne $prev_mod_time) {
       &update_mod_time($cur_mod_time, $v->{time_stamp});
       my $t = 
`/bin/echo "$v->{url_to_check} modified on $cur_mod_time\n" |
            /bin/mail -s "$k page just updated" $email`;
    }
}

# get current update time for the page
sub get_current {
    my $url = shift;
    my @headers = head($url);
    scalar localtime($headers[2]);
}

# get prev update time for the page
sub get_prev {
    my $file_timestamp = shift;
    unless (-e $file_timestamp) {
        open F,">$file_timestamp" or die $!;
        close F;
        return "bla bla";
    }
    open F,$file_timestamp or die $!;
    my $mod_time = <F>;
    close F;
    return $mod_time;
}

# record the update time for the page
sub update_mod_time {
    my ($mod_time,$file_timestamp) = @_;
    open F,">$file_timestamp" or die $!;
    print F $mod_time;
    close F;
}

[download]

In reply to webpage update watch - used to watch event update by Qiang

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.