Hi,
I'm beginning with mod_perl (mod_perl-1.99_05 + Apache 2.0.40 from
RedHat 8.0) and I want to write a module for rewriting the documents
that passes through the Apache proxy. So, I looked at the
Apache::AdBlocker
(http://perl.apache.org/docs/tutorials/tips/mod_perl_tricks/mod_perl_tricks.html#A_Banner_Ad_Blocker)
module and I'm facing some problems for writing the content of the
documents back to the client.
My main problem is that I get a SEGFAULT when calling the "$r->print()"
or "$r->send_http_header()" method.
I get the request, copy the headers from "headers_in", make my own
request with LWP, copy the headers to "headers_out", then it SEGFAULT
when writing the document ... Are this methods deprecated/not fully
implemented ? what is the correct way to write data to the client ?
The other problem is that if I use the "$r->push_handlers(PerlHandler =>
\&proxy_handler)" mechanism, my "proxy_handler()" function is never
called, so I do the work directly into the handler sub, is this ok ?
I attached my test module below (I register it with a "PerlTransHandler
Apache::Plop" statement in httpd.conf)
Thanks for your help,
Jérôme
--
package Apache::Plop;
use strict;
use Apache::RequestRec;
use Apache::RequestIO;
use Apache::RequestUtil;
use Apache::Const;
use Apache::ServerUtil;
use Apache::Response;
use APR::Table;
use LWP::UserAgent;
my $ua = LWP::UserAgent->new();
sub handler {
my $r = shift;
if( ! $r->proxyreq ) {
return Apache::DECLINED;
}
print STDERR "Good, this is a proxyreq ...\n";
# -->
# if I use this push_handlers, I never reach the "proxy_handler" sub
# So I commented it out and tried to do the work directly in "handler"
# $r->handler("perl-script"); #ok, let's do it
# $r->push_handlers(PerlHandler => \&proxy_handler);
#}
#
#sub proxy_handler {
# my $r = shift;
# <--
if( $r->method ne "GET" ) {
return Apache::DECLINED;
}
print STDERR "Good, this is a GET method ...\n";
# prepare the "real" request
my $request = HTTP::Request->new( $r->method, $r->uri );
# copy headers from client request
my %headers_in;
print STDERR "-- client headers --\n";
$r->headers_in()->do(
sub {
print STDERR "$_[0]: $_[1]\n";
$headers_in{$_[0]} = $_[1];
$request->header( {$_[0]}, $_[0] );
}
);
print STDERR "-- end --\n";
# make the "real" request myself
$ua->agent( $headers_in{ 'User-Agent' } );
my $response = $ua->request( $request );
if( ! $response->is_success() ) {
print STDERR "== ERROR ==\n";
return Apache::DECLINED;
}
print STDERR "-- server headers --\n";
my %headers_out;
$response->headers()->scan(
sub {
print STDERR "$_[0]: $_[1]\n";
$headers_out{$_[0]} = $_[1];
}
);
print STDERR "-- end --\n";
# simply override the content
my $content = $response->content;
$content = "<html><body>plop</body></html>";
# adjust the headers for the new content
$headers_out{ 'Content-length' } = length( $content );
$headers_out{ 'Content-type' } = 'text/html';
# copy the modified response headers back to Apache
foreach (keys %headers_out) {
$r->headers_out->{$_} = $headers_out{$_};
}
$r->content_type( $headers_out{ 'Content-type' } );
print STDERR "-- send/print --\n";
# -->
# here is where the SEGFAULT occurs
$r->send_http_header();
$r->print( $content );
# I don't know how to write a content back to the client :(
# <--
print STDERR "-- end --\n";
return Apache::OK;
}
1;
