MEDIUM: stream: support use-server rules with dynamic names
With server-template was introduced the possibility to scale the
number of servers in a backend without needing a configuration change
and associated reload. On the other hand it became impractical to
write use-server rules for these servers as they would only accept
existing server labels as argument. This patch allows the use of
log-format notation to describe targets of a use-server rules, such
as in the example below:
listen test
bind *:1234
use-server %[hdr(srv)] if { hdr(srv) -m found }
use-server s1 if { path / }
server s1 127.0.0.1:18080
server s2 127.0.0.1:18081
If a use-server rule is applied because it was conditionned by an
ACL returning true, but the target of the use-server rule cannot be
resolved, no other use-server rule is evaluated and we fall back to
load balancing.
This feature was requested on the ML, and bumped with issue #563.
6 files changed