James Lee wrote:
Hi mod_perl community, this is my first post so be gentle with me.
I'm trying to create something which translates a GET request into a POST
(creating the body dynamically) and then hand off the POST to another
server.
I have created a mod_perl connection filter to change the GET to a POST in
the request line. It also adds Content-Length and Content-Type headers and
this works fine.
I then have a request filter which creates the POST body. This works when
the request is handled by a PerlResponseHandler but I'm trying to offload
the request to mod_proxy as the responses can be quite large but I just
can't get it to play ball. I see the request filter being called but the
POST body never arrives at the target server. I suspect this is a timing
issue, ie: mod_proxy kicking in before my request filter but I'm not
certain.
Exactly. By the time your response handler is invoked, the time for mod_proxy
is long past.
One approach would be : have your PerlResponseHandler send the request directly to the
back-end server, using LWP, read the response, and return this response as the response
for your response handler. In other words, do yourself what mod_proxy would do.
Can anybody shed some light on this or correct my approach. I was going to
add the POST body in the connection filter but it seemed cleaner/easier to
do it in a request filter.
In the mod_perl documentation, there is somewhere a schema of the different Apache phases,
and when the different handlers get invoked. I beliebe mod_proxygets invoked somewhere
around the Fixup phase, so if you want to beat it, you have to be earlier than that.
I've looked on the mailing list and found a few things that touch on this (
http://tech.groups.yahoo.com/group/modperl/message/54541) but nothing that's
close enough to help.
Config below ... I've not included perl code as this message is quite long
anyway. Please let me know if it would be helpful.
Thanks in advance, James.
***
httpd.conf extract:
PerlInputFilterHandler Sample::RequestTweaker::change_get_to_post
<Location /reports>
PerlInputFilterHandler Sample::RequestTweaker::inject_post_data
ProxyPass http://appserver/reports-engine
</Location>
