[MEDIUM] add support for anonymous ACLs
Anonymous ACLs allow the declaration of rules which rely directly on
ACL expressions without passing via the declaration of an ACL. Example :
With named ACLs :
acl site_dead nbsrv(dynamic) lt 2
acl site_dead nbsrv(static) lt 2
monitor fail if site_dead
With anonymous ACLs :
monitor fail if { nbsrv(dynamic) lt 2 } || { nbsrv(static) lt 2 }
diff --git a/doc/configuration.txt b/doc/configuration.txt
index ccb7e1c..4e6f631 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -6216,6 +6216,36 @@
use_backend static if host_static or host_www url_static
use_backend www if host_www
+It is also possible to form rules using "anonymous ACLs". Those are unnamed ACL
+expressions that are built on the fly without needing to be declared. They must
+be enclosed between braces, with a space before and after each brace (because
+the braces must be seen as independant words). Example :
+
+ The following rule :
+
+ acl missing_cl hdr_cnt(Content-length) eq 0
+ block if METH_POST missing_cl
+
+ Can also be written that way :
+
+ block if METH_POST { hdr_cnt(Content-length) eq 0 }
+
+It is generally not recommended to use this construct because it's a lot easier
+to leave errors in the configuration when written that way. However, for very
+simple rules matching only one source IP address for instance, it can make more
+sense to use them than to declare ACLs with random names. Another example of
+good use is the following :
+
+ With named ACLs :
+
+ acl site_dead nbsrv(dynamic) lt 2
+ acl site_dead nbsrv(static) lt 2
+ monitor fail if site_dead
+
+ With anonymous ACLs :
+
+ monitor fail if { nbsrv(dynamic) lt 2 } || { nbsrv(static) lt 2 }
+
See section 4.2 for detailed help on the "block" and "use_backend" keywords.