haproxy/doc
Willy Tarreau 9a621ae76d MEDIUM: vars: add a new "set-var-fmt" action
The set-var() action is convenient because it preserves the input type
but it's a pain to deal with when trying to concatenate values. The
most recurring example is when it's needed to build a variable composed
of the source address and the source port. Usually it ends up like this:

    tcp-request session set-var(sess.port) src_port
    tcp-request session set-var(sess.addr) src,concat(":",sess.port)

This is even worse when trying to aggregate multiple fields from stick-table
data for example. Due to this a lot of users instead abuse headers from HTTP
rules:

    http-request set-header(x-addr) %[src]:%[src_port]

But this requires some careful cleanups to make sure they won't leak, and
it's significantly more expensive to deal with. And generally speaking it's
not clean. Plus it must be performed for each and every request, which is
expensive for this common case of ip+port that doesn't change for the whole
session.

This patch addresses this limitation by implementing a new "set-var-fmt"
action which performs the same work as "set-var" but takes a format string
in argument instead of an expression. This way it becomes pretty simple to
just write:

    tcp-request session set-var-fmt(sess.addr) %[src]:%[src_port]

It is usable in all rulesets that already support the "set-var" action.
It is not yet implemented for the global "set-var" directive (which already
takes a string) and the CLI's "set var" command, which would definitely
benefit from it but currently uses its own parser and engine, thus it
must be reworked.

The doc and regtests were updated.
2021-09-02 21:22:22 +02:00
..
design-thoughts DOC: assorted typo fixes in the documentation 2020-03-09 14:45:58 +01:00
internals CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
lua-api CLEANUP: assorted typo fixes in the code and comments 2021-08-25 05:13:31 +02:00
51Degrees-device-detection.txt CONTRIB: move 51Degrees to addons/51degrees 2021-04-02 17:48:42 +02:00
acl.fig
architecture.txt DOC: fix a few remainig cases of "Haproxy" and "HAproxy" in doc and comments 2021-05-09 06:50:46 +02:00
close-options.txt MINOR: config: reject long-deprecated "option forceclose" 2021-06-11 16:57:34 +02:00
coding-style.txt DOC: fix a few remainig cases of "Haproxy" and "HAproxy" in doc and comments 2021-05-09 06:50:46 +02:00
configuration.txt MEDIUM: vars: add a new "set-var-fmt" action 2021-09-02 21:22:22 +02:00
cookie-options.txt DOC: fix a few typos in the documentation 2018-11-18 22:23:15 +01:00
DeviceAtlas-device-detection.txt CONTRIB: move src/da.c and contrib/deviceatlas to addons/deviceatlas 2021-04-02 17:48:42 +02:00
gpl.txt
haproxy.1 DOC: add description of pidfile in master-worker mode 2020-08-26 18:40:53 +02:00
intro.txt DOC: intro: Fix typo in starter guide 2021-05-27 08:26:43 +02:00
lgpl.txt
linux-syn-cookies.txt DOC: add doc/linux-syn-cookies.txt 2015-08-11 12:17:41 +02:00
lua.txt [RELEASE] Released version 2.4-dev19 2021-05-10 07:50:26 +02:00
management.txt MEDIUM: server: allow to remove servers at runtime except non purgeable 2021-08-25 15:53:54 +02:00
netscaler-client-ip-insertion-protocol.txt DOC: fix typos 2019-05-25 07:34:24 +02:00
network-namespaces.txt MAJOR: namespace: add Linux network namespace support 2014-11-21 07:51:57 +01:00
peers-v2.0.txt DOC: peers: fix the protocol tag name in the doc 2021-05-09 06:38:07 +02:00
peers.txt DOC: peers: Update for dictionary cache entries for peers protocol. 2019-06-07 15:47:54 +02:00
proxy-protocol.txt DOC: fix a few remainig cases of "Haproxy" and "HAproxy" in doc and comments 2021-05-09 06:50:46 +02:00
queuing.fig
regression-testing.txt DOC: fix a few remainig cases of "Haproxy" and "HAproxy" in doc and comments 2021-05-09 06:50:46 +02:00
seamless_reload.txt CLEANUP: removed obsolete examples an move a few to better places 2019-06-15 21:25:06 +02:00
SOCKS4.protocol.txt MEDIUM: connection: Upstream SOCKS4 proxy support 2019-05-31 17:24:06 +02:00
SPOE.txt CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
WURFL-device-detection.txt CONTRIB: move src/wurfl.c and contrib/wurfl to addons/wurfl 2021-04-02 17:48:42 +02:00