haproxy/reg-tests
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
..

                 * Regression testing for HAProxy with VTest *


This little README file is about how to compile and run vtest test case files (VTC files)
to test HAProxy for any regression.

To do so, you will have to compile vtest program sources which depends on
Varnish cache application sources. vtest, formerly varnishtest, is a very useful
program which has been developed to test Varnish cache application. vtest has been
modified in collaboration with Varnish cache conceptor Poul-Henning Kamp to support
HAProxy in addition to Varnish cache.

See also: doc/regression-testing.txt

* vtest compilation *

    $ git clone https://github.com/vtest/VTest

    $ cd VTest

    $ make vtest

  Then vtest program may be found at the root directory of vtest sources directory.
  The Varnish cache manuals are located in 'man' directory of Varnish cache sources
  directory. You will have to have a look at varnishtest(7) and vtc(7) manuals to
  use vtest.

  Some information may also be found in doc/regression-testing.txt in HAProxy
  sources.

  Note that VTC files for Varnish cache may be found in bin/varnishtest/tests directory
  of Varnish cache sources directory which may be found here:
  https://github.com/varnishcache/varnish-cache


* vtest execution *

  You must set HAPROXY_PROGRAM environment variable to give the location
  of the HAProxy program to test to vtest:

    $ HAPROXY_PROGRAM=<my haproxy program> vtest ...

  The HAProxy VTC files found in HAProxy sources may be run with the reg-tests
  Makefile target. You must set the VTEST_PROGRAM environment variable to
  give the location of the vtest program which has been previously compiled.

    $ VTEST_PROGRAM=<my vtest program> make reg-tests

  "reg-tests" Makefile target run scripts/run-regtest.sh script.
  To get more information about this script run it with --help option.

  Note that vtest is run with -t10 and -l option. -l option is to keep
  keep vtest temporary directory in case of failed test cases. core files
  may be found in this directory (if enabled by ulimit).


* vtest patches for HAProxy VTC files *

  When producing a patch to add a VTC regression testing file to reg-tests directory,
  please follow these simple rules:

    - If your VTC file needs others files, if possible, use the same basename as that
      of the VTC file,
    - Put these files in a directory with the same name as the code area concerned
      by the bug ('peers', 'lua', 'acl' etc).