MINOR: doc: Add information about "early-hint" http-request action.

diff --git a/doc/configuration.txt b/doc/configuration.txt
index 52cc4328e3847fb153c8e7a96a92a9f7ed485103..349dfab3da5232952d274ca03fc7151ce97d55b4 100644 (file)
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -4130,6 +4130,16 @@ http-request deny [deny_status <status>] [ { if | unless } <condition> ]
   those that can be overridden by the "errorfile" directive.
   No further "http-request" rules are evaluated.
 
+http-request early-hint <name> <fmt> [ { if | unless } <condition> ]
+
+  This is used to build an HTTP 103 Early Hints response prior to any other one.
+  This appends an HTTP header field to this response whose name is specified in
+  <name> and whose value is defined by <fmt> which follows the log-format rules
+  (see Custom Log Format in section 8.2.4). This is particularly useful to pass
+  to the client som
+
+  See RFC 8297 for more information.
+
 http-request redirect <rule> [ { if | unless } <condition> ]
 
   This performs an HTTP redirection based on a redirect rule. This is exactly