mod_perl: how to display the error message within the ErrorDocument

projekt21 has asked for the wisdom of the Perl Monks concerning the following question:

I want to handle ErrorDocuments with a mod_perl module Apache::MyError in a way that the actual error message (server error 500, as written to the logs) is displayed within the result HTML page.

I know that this is evil, just treat it as an academic approach. (What I want to do in real life is mail the message to the webmaster and display a backtrace id to the user referring to that error)

What I have so far is my httpd.conf,

ErrorDocument 500 /errors/500

<Location /errors>
  SetHandler  perl-script
  PerlHandler Apache::MyError
  Options +ExecCGI
  PerlSendHeader On
</Location>
[download]

a script that won't compile under /usr/local/apache/cgi-bin/die.pl and the following:

package Apache::Error;
use strict;
use Apache::Constants qw(:common);

sub handler {

  my $r = Apache->request; 
  my $p = $r->prev;

  $r->status(OK);
  $r->content_type("text/html");
  $r->send_http_header;
  $r->print("<pre>\n");

  $r->print($r->path_info, "\n");
  $r->print($p->notes("error-notes"), "\n");

  $r->print("</pre>\n");

  return OK;
}

1;
[download]

The log says:

syntax error at /usr/local/apache/cgi-bin/die.pl line 6, near "if {"
Missing right curly or square bracket at /usr/local/apache/cgi-bin/die
+.pl line 8, at end of line
Execution of /usr/local/apache/cgi-bin/die.pl aborted due to compilati
+on errors.
[Mon Sep 30 13:42:51 2002] [error] [client xxx.xxx.xxx.xxx] Premature 
+end of script headers: /usr/local/apache/cgi-bin/die.pl
[download]

$p->notes("error-notes") contains "premature end of ..." but not the "syntax error ..." which is the one I want to have.

Can someone guide me to a solution (I know one from mod_ruby using the method error_message)? Am I missing something?

alex pleiner <alex@zeitform.de>
zeitform Internet Dienste

Comment on mod_perl: how to display the error message within the ErrorDocument Select or Download Code

Replies are listed 'Best First'.
Re: mod_perl: how to display the error message within the ErrorDocument by spartacus9 (Beadle) on Sep 30, 2002 at 13:27 UTC
Instead of Apache::Error, you might consider CGI::Carp. This would have to be done at the script level rather than the server level. There is an option with CGI::Carp that will allow you to both display the server error reason on the screen in HTML and also e-mail the error to a specified e-mail address. For instance: Contents of CatchErrors.pm follows: ----------------------------------- use strict; use CGI::Carp qw(fatalsToBrowser set_message); use Mail::Sender; BEGIN { sub email_problem { my $sender = new Mail::Sender({ from => 'errors@yourdomain.com', smtp => 'smtp.server.com'}); $sender->MailMsg({ to => $Error::email, subject => $ENV{SCRIPT_NAME}, msg => $_[0]}); print "Website Error"; } set_message(\&email_problem); } sub import { $Error::email = $_[1] \|\| 'errors@yourdomain.com'; } 1; -------------------------------------- Then, in your perl script, simply include the following line: use CatchErrors qw(recipient@yourdomain.com); [download] Using this method, you should be able to redirect all of the script's errors to an e-mail address you specify when you "use" the package.	[reply] [d/l]
Re: mod_perl: how to display the error message within the ErrorDocument by shotgunefx (Parson) on Sep 30, 2002 at 13:29 UTC
From perl.apache.org, Redirecting Errors to the Client Instead of Error Log (For specific instances, not for use in an ErrorDocument I think) -Lee "To be civilized is to deny one's nature."	[reply]
Re: mod_perl: how to display the error message within the ErrorDocument by zigdon (Deacon) on Sep 30, 2002 at 13:15 UTC
I think you're confusing the apache error and the perl error. While both are written by default to apache's error log, I'm guessing the "error-notes" does not capture STDERR of your perl script. Not sure how you'd get the error from the script passed to apache though -- Dan	[reply]
Re: Re: mod_perl: how to display the error message within the ErrorDocument by projekt21 (Friar) on Sep 30, 2002 at 13:20 UTC
Right, when I run the dying CGI under Apache::Registry I get what I want. But as the error is logged into my apache error log, I hoped that I could somehow get the message into my module, too. Looks like it won't work, hmmm. alex pleiner <alex@zeitform.de> zeitform Internet Dienste	[reply]


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