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Willy Tarreau 54496a6a5b MINOR: vars: make the vars() sample fetch function support a default value
It is quite common to see in configurations constructions like the
following one:

    http-request set-var(txn.bodylen) 0
    http-request set-var(txn.bodylen) req.hdr(content-length)
    ...
    http-request set-header orig-len %[var(txn.bodylen)]

The set-var() rules are almost always duplicated when manipulating
integers or any other value that is mandatory along operations. This is
a problem because it makes the configurations complicated to maintain
and slower than needed. And it becomes even more complicated when several
conditions may set the same variable because the risk of forgetting to
initialize it or to accidentally reset it is high.

This patch extends the var() sample fetch function to take an optional
argument which contains a default value to be returned if the variable
was not set. This way it becomes much simpler to use the variable, just
set it where needed, and read it with a fall back to the default value:

    http-request set-var(txn.bodylen) req.hdr(content-length)
    ...
    http-request set-header orig-len %[var(txn.bodylen,0)]

The default value is always passed as a string, thus it will experience
a cast to the output type. It doesn't seem userful to complicate the
configuration to pass an explicit type at this point.

The vars.vtc regtest was updated accordingly.
2021-09-03 12:08:54 +02:00
.github CI: Github Actions: temporarily disable BoringSSL builds 2021-09-02 17:32:43 +02:00
addons BUILD: opentracing: fixed build when using pkg-config utility 2021-08-01 18:18:29 +02:00
admin MINOR: systemd: remove the ExecStartPre line in the unit file 2021-08-20 23:36:45 +02:00
dev CLEANUP: dev/flags: remove useless test in the stdin number parser 2021-04-03 15:29:10 +02:00
doc MINOR: vars: make the vars() sample fetch function support a default value 2021-09-03 12:08:54 +02:00
examples MEDIUM: proxy: remove long-broken 'option http_proxy' 2021-07-18 19:35:32 +02:00
include MINOR: vars: make vars_get_by_* support an optional default value 2021-09-03 12:08:54 +02:00
reg-tests MINOR: vars: make the vars() sample fetch function support a default value 2021-09-03 12:08:54 +02:00
scripts BUILD: adopt script/build-ssl.sh for OpenSSL-3.0.0beta2 2021-08-25 05:16:00 +02:00
src MINOR: vars: make the vars() sample fetch function support a default value 2021-09-03 12:08:54 +02:00
tests CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
.cirrus.yml CI: introduce scripts/build-vtest.sh for installing VTest 2021-05-18 10:48:30 +02:00
.gitattributes MINOR: Configure the cpp userdiff driver for *.[ch] in .gitattributes 2021-02-22 18:17:57 +01:00
.gitignore DOC: lua-api: Add documentation about lua filters 2021-08-15 20:56:44 +02:00
.travis.yml CI: travis-ci: temporarily disable arm64 builds 2021-08-07 07:28:15 +02:00
BRANCHES DOC: fix some spelling issues over multiple files 2021-01-08 14:53:47 +01:00
CHANGELOG [RELEASE] Released version 2.5-dev5 2021-08-28 13:46:11 +02:00
CONTRIBUTING CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
INSTALL CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
LICENSE LICENSE: add licence exception for OpenSSL 2012-09-07 13:52:26 +02:00
MAINTAINERS CONTRIB: move spoa_example out of the tree 2021-04-21 09:39:06 +02:00
Makefile BUILD: globally enable -Wundef 2021-08-30 10:16:30 +02:00
README DOC: create a BRANCHES file to explain the life cycle 2019-06-15 22:00:14 +02:00
ROADMAP DOC: update the outdated ROADMAP file 2019-06-15 21:59:54 +02:00
SUBVERS BUILD: use format tags in VERDATE and SUBVERS files 2013-12-10 11:22:49 +01:00
VERDATE [RELEASE] Released version 2.5-dev5 2021-08-28 13:46:11 +02:00
VERSION [RELEASE] Released version 2.5-dev5 2021-08-28 13:46:11 +02:00

The HAProxy documentation has been split into a number of different files for
ease of use.

Please refer to the following files depending on what you're looking for :

  - INSTALL for instructions on how to build and install HAProxy
  - BRANCHES to understand the project's life cycle and what version to use
  - LICENSE for the project's license
  - CONTRIBUTING for the process to follow to submit contributions

The more detailed documentation is located into the doc/ directory :

  - doc/intro.txt for a quick introduction on HAProxy
  - doc/configuration.txt for the configuration's reference manual
  - doc/lua.txt for the Lua's reference manual
  - doc/SPOE.txt for how to use the SPOE engine
  - doc/network-namespaces.txt for how to use network namespaces under Linux
  - doc/management.txt for the management guide
  - doc/regression-testing.txt for how to use the regression testing suite
  - doc/peers.txt for the peers protocol reference
  - doc/coding-style.txt for how to adopt HAProxy's coding style
  - doc/internals for developer-specific documentation (not all up to date)