From: Willy Tarreau <w@1wt.eu>
Date: Fri, 23 Oct 2020 16:02:54 +0000 (+0200)
Subject: MINOR: stats: indicate the number of servers in a backend's status
X-Git-Tag: v2.3-dev8~9
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=2fbe6940f4cce550928fd665df4a48b9d0df99b5;p=thirdparty%2Fhaproxy.git

MINOR: stats: indicate the number of servers in a backend's status

When dumping the stats page (or the CSV output), when many states are
mixed, it's hard to figure the number of up servers. But when showing
only the "up" servers or hiding the "maint" servers, there's no way to
know how many servers are configured, which is problematic when trying
to update server-templates.

What this patch does, for dumps in "up" or "no-maint" modes, is to add
after the backend's "UP" or "DOWN" state "(%d/%d)" indicating the number
of servers seen as UP to the total number of servers in the backend. As
such, seeing "UP (33/39)" immediately tells that there are 6 servers that
are not listed when using "up", or will let the client figure how many
servers are left once deducted the number of non-maintenance ones. It's
not done on default dumps so as not to disturb existing tools, which
already have all the information they need in the dump.
---

diff --git a/src/stats.c b/src/stats.c
index fe027653db..a332e7cc7e 100644
--- a/src/stats.c
+++ b/src/stats.c
@@ -2148,10 +2148,23 @@ int stats_fill_be_stats(struct proxy *px, int flags, struct field *stats, int le
 {
 	long long be_samples_counter;
 	unsigned int be_samples_window = TIME_STATS_SAMPLES;
+	struct buffer *out = get_trash_chunk();
+	const struct server *srv;
+	int nbup, nbsrv;
+	char *fld;
 
 	if (len < ST_F_TOTAL_FIELDS)
 		return 0;
 
+	nbup = nbsrv = 0;
+	if (flags & (STAT_HIDE_MAINT|STAT_HIDE_DOWN)) {
+		for (srv = px->srv; srv; srv = srv->next) {
+			if (srv->cur_state != SRV_ST_STOPPED)
+				nbup++;
+			nbsrv++;
+		}
+	}
+
 	stats[ST_F_PXNAME]   = mkf_str(FO_KEY|FN_NAME|FS_SERVICE, px->id);
 	stats[ST_F_SVNAME]   = mkf_str(FO_KEY|FN_NAME|FS_SERVICE, "BACKEND");
 	stats[ST_F_MODE]     = mkf_str(FO_CONFIG|FS_SERVICE, proxy_mode_str(px->mode));
@@ -2173,7 +2186,13 @@ int stats_fill_be_stats(struct proxy *px, int flags, struct field *stats, int le
 	stats[ST_F_EINT]     = mkf_u64(FN_COUNTER, px->be_counters.internal_errors);
 	stats[ST_F_CONNECT]  = mkf_u64(FN_COUNTER, px->be_counters.connect);
 	stats[ST_F_REUSE]    = mkf_u64(FN_COUNTER, px->be_counters.reuse);
-	stats[ST_F_STATUS]   = mkf_str(FO_STATUS, (px->lbprm.tot_weight > 0 || !px->srv) ? "UP" : "DOWN");
+
+	fld = chunk_newstr(out);
+	chunk_appendf(out, "%s", (px->lbprm.tot_weight > 0 || !px->srv) ? "UP" : "DOWN");
+	if (flags & (STAT_HIDE_MAINT|STAT_HIDE_DOWN))
+		chunk_appendf(out, " (%d/%d)", nbup, nbsrv);
+
+	stats[ST_F_STATUS]   = mkf_str(FO_STATUS, fld);
 	stats[ST_F_WEIGHT]   = mkf_u32(FN_AVG, (px->lbprm.tot_weight * px->lbprm.wmult + px->lbprm.wdiv - 1) / px->lbprm.wdiv);
 	stats[ST_F_ACT]      = mkf_u32(0, px->srv_act);
 	stats[ST_F_BCK]      = mkf_u32(0, px->srv_bck);