From ff2b7afe0b72874e158400aaa58f413dda030489 Mon Sep 17 00:00:00 2001
From: Willy Tarreau <w@1wt.eu>
Date: Fri, 13 Oct 2017 11:46:26 +0200
Subject: [PATCH] MINOR: server: add the srv_queue() sample fetch method

srv_queue([<backend>/]<server>) : integer
  Returns an integer value corresponding to the number of connections currently
  pending in the designated server's queue. If <backend> is omitted, then the
  server is looked up in the current backend. It can sometimes be used together
  with the "use-server" directive to force to use a known faster server when it
  is not much loaded. See also the "srv_conn", "avg_queue" and "queue" sample
  fetch methods.
---
 doc/configuration.txt |  8 ++++++++
 src/backend.c         | 14 ++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/doc/configuration.txt b/doc/configuration.txt
index c3aa6fa84..c7359a85f 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -13373,6 +13373,14 @@ srv_is_up([<backend>/]<server>) : boolean
   using dummy servers as boolean variables that can be enabled or disabled from
   the CLI, so that rules depending on those ACLs can be tweaked in realtime.
 
+srv_queue([<backend>/]<server>) : integer
+  Returns an integer value corresponding to the number of connections currently
+  pending in the designated server's queue. If <backend> is omitted, then the
+  server is looked up in the current backend. It can sometimes be used together
+  with the "use-server" directive to force to use a known faster server when it
+  is not much loaded. See also the "srv_conn", "avg_queue" and "queue" sample
+  fetch methods.
+
 srv_sess_rate([<backend>/]<server>) : integer
   Returns an integer corresponding to the sessions creation rate on the
   designated server, in number of new sessions per second. If <backend> is
diff --git a/src/backend.c b/src/backend.c
index 52adab009..06f15a1ca 100644
--- a/src/backend.c
+++ b/src/backend.c
@@ -1798,6 +1798,19 @@ smp_fetch_srv_conn(const struct arg *args, struct sample *smp, const char *kw, v
 	return 1;
 }
 
+/* set temp integer to the number of connections pending in the server's queue.
+ * Accepts exactly 1 argument. Argument is a server, other types will lead to
+ * undefined behaviour.
+ */
+static int
+smp_fetch_srv_queue(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	smp->flags = SMP_F_VOL_TEST;
+	smp->data.type = SMP_T_SINT;
+	smp->data.u.sint = args->data.srv->nbpend;
+	return 1;
+}
+
 /* set temp integer to the number of enabled servers on the proxy.
  * Accepts exactly 1 argument. Argument is a server, other types will lead to
  * undefined behaviour.
@@ -1845,6 +1858,7 @@ static struct sample_fetch_kw_list smp_kws = {ILH, {
 	{ "srv_conn",      smp_fetch_srv_conn,       ARG1(1,SRV), NULL, SMP_T_SINT, SMP_USE_INTRN, },
 	{ "srv_id",        smp_fetch_srv_id,         0,           NULL, SMP_T_SINT, SMP_USE_SERVR, },
 	{ "srv_is_up",     smp_fetch_srv_is_up,      ARG1(1,SRV), NULL, SMP_T_BOOL, SMP_USE_INTRN, },
+	{ "srv_queue",     smp_fetch_srv_queue,      ARG1(1,SRV), NULL, SMP_T_SINT, SMP_USE_INTRN, },
 	{ "srv_sess_rate", smp_fetch_srv_sess_rate,  ARG1(1,SRV), NULL, SMP_T_SINT, SMP_USE_INTRN, },
 	{ /* END */ },
 }};