Automated web client to wait for results page

this example from a Well House Consultants training course
More on this [link]

This example is described in the following article(s):
• Automating access to a page obscured behind a holding page - [link]

This example references the following resources:
http://www.wellho.net/demo/dozen.php

Source code: coojar Module: A805

use LWP::UserAgent;

# This script uses the LWP module to read back a series
# of response pages from a server - the "holding" pages
# followed by the actual results - and presents the
# automatic results.

# Note that there are several methods that a web site can
# use to present delayed results after a holding page - it
# could be done via server push (using a multipart response)
# or client pull with a refresh header, or using javascipt
# in the browser. This is a client pull example and the code
# would be very different if you werw writing it for a web
# site that uses one of the other approaches.

# Set up thsi program as a browser

my $ua = LWP::UserAgent->new;
$ua->agent("Automated Waiting Script");

# Set it up to handle cookies between pages in the client
# pull series (the server we are using sends a cookie with the
# first response which the client must then use when it asks
# "how are you getting on?" of the server. For this demo, it's
# OK if the following fails to read any existing set of cookies,
# as the only one that matters is the one between the pages of the
# application.

my $jar = $ua->cookie_jar({
  file => "/home/wellho/testing/cookies",
  hide_cookie2 => 1,
  autosave => 1,
  ignore_discard => 1});

# Call up a response, and keep calling up until you get one which
# does NOT include the refresh header.

while (1) {
        $response = $ua -> get("http://www.wellho.net/demo/dozen.php");
        $body = $response->content();

        # Extract information and report on progress
        # Just to show how the demo is working!
        ($report) = $body =~ /%start%(.*)%end%/s;
        print "Intermediate: $report\n";

        # Do we have a refresh header (regex could be far more
        # general and robust here!)? If we do have a refresh
        # header, honour its wait time. If we don't exit the
        # loop as we have the final result.
        if (($twait) = $body =~ m!(\d+); URL=/demo/dozen.php!) {
                sleep $twait;
        } else {
                last;
        }
}

# No more refresh headers - we have the final result now!
print "FINAL RESULT: $report\n";

__END__

Sample results from running this program:

-bash-3.2$ perl coojar
Intermediate: Running ... 0 seconds gone
Intermediate: Running ... 5 seconds gone
Intermediate: Running ... 10 seconds gone
Intermediate: Running ... 15 seconds gone
Intermediate: Completed ...
03:47:40 up 3 days, 11:52, 1 user, load average: 0.41, 0.45, 0.27

FINAL RESULT: Completed ...
03:47:40 up 3 days, 11:52, 1 user, load average: 0.41, 0.45, 0.27

-bash-3.2$

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