The apache config for modperl is as follows:
## Load mod_perl
LoadModule perl_module /usr/lib/apache2/modules/mod_perl.so
PerlModule Apache2::Reload
PerlInitHandler Apache2::Reload
PerlOptions +Parent
PerlSwitches -Mlib=/var/www/includes
<Location />
DirectoryIndex index.pl index.html
#AddHandler cgi-script .pl
AddHandler perl-script .pl
PerlResponseHandler ModPerl::Registry
Options Indexes FollowSymLinks ExecCGI
Require all granted
</Location>
To test between the two options, I change the comment for AddHandler.
On 14/5/24 13:21, Joseph He wrote:
Steven, how do you put your script under the mod-perl environment? What
is your httpd.conf file? Thx.
On Mon, May 13, 2024 at 10:00 PM Steven Haigh via modperl
<modperl@perl.apache.org <mailto:modperl@perl.apache.org>> wrote:
I wonder if perhaps I haven't been clear in the problem.
In the provided code example:
my $cmd = "/bin/stdbuf";
my @args = qw@ -o1 -e1 /usr/bin/speedtest-cli@;
print '<pre class="alert">'; <-- appears in the HTML output.
my $pid = open3(0, \*READER, 0, $cmd, @args);
while ( my $output = <READER> ) {
print $output; <-- This never outputs anything.
}
print "Speed test complete.</pre>"; <-- appears in the HTML
output.
waitpid $pid,0;
If I was to guess, it seems like an interaction with open3 and modperl.
https://perldoc.perl.org/IPC::Open3
<https://perldoc.perl.org/IPC::Open3>
The syntax is basically:
my $pid = open3( <input>, <stdout>, <stderr>, $cmd, @args );
If I understand it right, I give it a filehandle - which I then read
from. The executed command is then:
/bin/stdbuf -o1 -e1 /usr/bin/speedtest-cli
The inclusion of using stdbuf with these options are to stream the
ouput
line after line, and not whatever terminal buffer is in place that will
return the output in a chunk.
However, all output from running the command ends up in the apache logs.
That means that <READER> never gets anything, and therefore the
print is
never called.
Does that make more sense?
On 14/5/24 12:46, Joseph He wrote:
> Steven, you need to use those mod-perl libraries to handle the web
> request and to generate the response.
>
> https://perl.apache.org/docs/2.0/user/intro/start_fast.html
<https://perl.apache.org/docs/2.0/user/intro/start_fast.html>
> <https://perl.apache.org/docs/2.0/user/intro/start_fast.html
<https://perl.apache.org/docs/2.0/user/intro/start_fast.html>>
>
> Scroll down to the bottom, you can see how to output the content.
>
> Cheers,
> Joseph
>
>
> On Mon, May 13, 2024 at 9:35 PM Steven Haigh via modperl
> <modperl@perl.apache.org <mailto:modperl@perl.apache.org>
<mailto:modperl@perl.apache.org <mailto:modperl@perl.apache.org>>>
wrote:
>
> That being said, is there a way to output to the web page in this
> scenario?
>
> On 14/5/24 12:15, Joseph He wrote:
> > CGI script runs on its own process. mod-perl basically
wraps CGI
> script
> > into apache process, that is why its output is automatically
> going to
> > Apache log.
> >
> > On Mon, May 13, 2024 at 1:53 AM Steven Haigh via modperl
> > <modperl@perl.apache.org <mailto:modperl@perl.apache.org>
<mailto:modperl@perl.apache.org <mailto:modperl@perl.apache.org>>
> <mailto:modperl@perl.apache.org
<mailto:modperl@perl.apache.org> <mailto:modperl@perl.apache.org
<mailto:modperl@perl.apache.org>>>>
> wrote:
> >
> > Hi all,
> >
> > I'm playing around with mod_perl on apache on docker - and
> now I've
> > finally got all the module issues sorted, I'm trying to
> figure out why
> > when using mod_perl, the output of scripts ends up in the
> apache logs.
> >
> > The following configuration works, and the output of
shelled
> scripts
> > works as expected:
> >
> > <Location />
> > DirectoryIndex index.pl <http://index.pl>
<http://index.pl <http://index.pl>>
> <http://index.pl <http://index.pl> <http://index.pl
<http://index.pl>>> index.html
> > AddHandler cgi-script .pl
> > Options +Indexes +FollowSymLinks +ExecCGI
> > Require all granted
> > </Location>
> >
> > If I change this to use mod_perl, all output from
scripts run
> in web
> > pages ends up in the apache log:
> >
> > <Location />
> > DirectoryIndex index.pl <http://index.pl>
<http://index.pl <http://index.pl>>
> <http://index.pl <http://index.pl> <http://index.pl
<http://index.pl>>> index.html
> > AddHandler perl-script .pl
> > Options +Indexes +FollowSymLinks +ExecCGI
> > Require all granted
> > </Location>
> >
> > The perl code I'm using in the web page is as follows:
> > my $cmd = "/bin/stdbuf";
> > my @args = qw@ -o1 -e1 /usr/bin/speedtest-cli@;
> >
> > print '<pre class="alert">';
> > my $pid = open3(0, \*READER, 0, $cmd, @args);
> > while ( my $output = <READER> ) {
> > print $output;
> > }
> > print "Speed test complete.</pre>";
> > waitpid $pid,0;
> >
> > Does anyone have any clues as to why STDOUT would end
up in
> the apache
> > log and not in the web page being served when using
> perl-script as the
> > handler?
> >
> > --
> > Steven Haigh
> >
> > 📧 net...@crc.id.au <mailto:net...@crc.id.au>
<mailto:net...@crc.id.au <mailto:net...@crc.id.au>>
> <mailto:net...@crc.id.au <mailto:net...@crc.id.au>
<mailto:net...@crc.id.au <mailto:net...@crc.id.au>>>
> > 💻 https://crc.id.au <https://crc.id.au>
<https://crc.id.au <https://crc.id.au>> <https://crc.id.au
<https://crc.id.au>
> <https://crc.id.au <https://crc.id.au>>>
> >
> >
>
> --
> Steven Haigh
>
> 📧 net...@crc.id.au <mailto:net...@crc.id.au>
<mailto:net...@crc.id.au <mailto:net...@crc.id.au>>
> 💻 https://crc.id.au <https://crc.id.au> <https://crc.id.au
<https://crc.id.au>>
>
--
Steven Haigh
📧 net...@crc.id.au <mailto:net...@crc.id.au>
💻 https://crc.id.au <https://crc.id.au>
--
Steven Haigh
📧 net...@crc.id.au
💻 https://crc.id.au
