sara2005 has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks,

I run CGI programs for executing long processes (thanks to merlyn ), which is working fine in Unix.

I got a little greedy :) and wanted to implement a progress bar, which should read a status file in the server and display the percentage complete in the web browser. The status file can be as simple as 

task name
completed=45%

[download]

If this can be translated in the browser as 

Executing task: <task name>
#########--------------- (this is % complete in bars)

[download]

Unfortunately, I was not able to find any modules in CPAN that can achieve this. Can someone provide some hints on how to get this done?

Replies are listed 'Best First'.
Re: Progress bar for CGI by reading a file
by freakingwildchild (Scribe) on Jun 17, 2006 at 05:22 UTC
    Maybe this might help you out CGI::ProgressBar. Example code: 
    use strict;
        use warnings;
        use CGI::ProgressBar qw/:standard/;
        $| = 1; # Do not buffer output
        print header,
                start_html(
                        -title=>'A Simple Example',
                        -style=>{
                                -src  => '', # You can override the ba
+r style here
                                -code => '', # or inline, here.
                        }
                ),
                h1('A Simple Example'),
                p('This example will update a JS/CSS progress bar.'),
                progress_bar( -from=>1, -to=>100 );
        # We're set to go.
        for (1..10){
                print update_progress_bar;
                # Simulate being busy:
                sleep 1;
        }
        # Now we're done, get rid of the bar:
        print hide_progress_bar;
        print p('All done.');
        print end_html;
        exit;

    [download]
[reply]
[d/l]
Re: Progress bar for CGI by reading a file
by lima1 (Curate) on Jun 17, 2006 at 00:11 UTC
    I'm quite sure that any of this myriad of new AJAX libraries has something like this. The rough idea: you have to generate and update a XML file containing the percentage in your perl code and some javascript stuff updates your webpage.

    google for it, I think a progress bar is the AJAX "Hello World" program ;)

[reply]
Re: Progress bar for CGI by reading a file
by TedPride (Priest) on Jun 17, 2006 at 01:25 UTC
    Have your script update a small HTML file every so often with the current percentage, and run it in a frames layout, with one frame being the main script and the other (on refresh every 5 sec or so) the percentage file.
[reply]

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