Re: Header compression (or lack of) in mod_proxy

[Graham Leggett]

Paul Fee wrote:

Could someone point out a reason for the different behaviour in the 
request and response path?


Cookies.

Cookie headers cannot be compressed as the RFC says they should be, so 
proxy works around this by not compressing headers.


How about making the behaviour configurable so that it's consistent 
in both directions and if necessary the headers can be left in 
their original uncompressed form?


In theory, the idea that it be consistent in both directions is not 
unreasonable - it follows the principle of "be lenient in what we accept".


Regards,
Graham
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Header compression (or lack of) in mod_proxy

[Paul Fee]

Hello all,

I'm using Apache as a HTTP proxy.  Regarding the request and 
response headers, I've done some tests and noticed different 
behaviour in the request and response direction.

The request headers are compressed (i.e. headers with same name are 
merged into one header and comma separated). e.g.

hdr: value1
hdr: value2

becomes,
hdr: value1, value2

This due to ap_get_mime_headers_core() calling 
apr_table_compress().  It occurs in protocol.c before Apache even 
detects that the incoming request is a proxy request.

The response headers on the other hand are read by mod_proxy in 
ap_proxy_read_headers() which calls apr_table_add() but not 
apr_table_compress().

RFC 2616 states that header compression MUST be allowed.

However if a proxy is between a non-compliant client and/or server 
then it would be best to leave the headers in their original form.  
If a direct connection works and a proxied connection fails then 
the proxy will be perceived as the problem.

Could someone point out a reason for the different behaviour in the 
request and response path?

How about making the behaviour configurable so that it's consistent 
in both directions and if necessary the headers can be left in 
their original uncompressed form?

By the way, my tests were on httpd 2.0.59, however reading the 
source for 2.2.3 suggests the same behaviour.

Thanks for your time,
Paul


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NSIS/silent install question..

[Kevin White]

I am interested in installing apache onto a win32 
target, and changing some install options along the way.  What would be my 
best option?  Does the win32 apache install still use NSIS?  Is the 
.nsi script available?
 
Thanks,
 
-Kevin

mod_ext_filter and HTTP status codes

[Craig Sebenik]

Is there any way to have an external program (called via mod_ext_filter) 
tell the server to return a different status code (other than 200). 
Specifically, I want to be able to set a 500 error.

Also, a "nice to have" would be a way to set other HTTP headers (like 
Last-Modified).

Conceptually, I'm not even sure how that would work... maybe via the ext 
program's exit codes?

Any ideas would be appreciated.

TIA
Craig