From 6f1fb53cc1f668ccc75c29688cf98129040fc8c9 Mon Sep 17 00:00:00 2001
From: Christopher Faulet <cfaulet@haproxy.com>
Date: Mon, 29 Jan 2024 16:41:42 +0100
Subject: [PATCH] MEDIUM: promex: Dump backends extra counters if requested

Dump extra counter for the backend. We loop on stats modules and dumped all
concerned counters. The module name is reported with the "mod" label.
---
 addons/promex/service-prometheus.c | 61 ++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/addons/promex/service-prometheus.c b/addons/promex/service-prometheus.c
index 1fe123dd6..0dceaa34e 100644
--- a/addons/promex/service-prometheus.c
+++ b/addons/promex/service-prometheus.c
@@ -1070,6 +1070,67 @@ static int promex_dump_back_metrics(struct appctx *appctx, struct htx *htx)
 		ctx->px = proxies_list;
 	}
 
+	/* Skip extra counters */
+	if (!(ctx->flags & PROMEX_FL_EXTRA_COUNTERS))
+		goto end;
+
+	if (!ctx->mod) {
+		/* no restart point, get the first module in the list */
+		ctx->mod = LIST_NEXT(&stats_module_list[STATS_DOMAIN_PROXY], typeof(ctx->mod), list);
+		ctx->mod_field_num = 0;
+	}
+
+	list_for_each_entry_from(ctx->mod, &stats_module_list[STATS_DOMAIN_PROXY], list) {
+		void *counters;
+
+		if (!(stats_px_get_cap(ctx->mod->domain_flags) & STATS_PX_CAP_BE)) {
+			ctx->field_num += ctx->mod->stats_count;
+			ctx->mod_field_num = 0;
+			continue;
+		}
+
+		for (;ctx->mod_field_num < ctx->mod->stats_count; ctx->mod_field_num++) {
+			while (ctx->px) {
+				struct promex_label labels[PROMEX_MAX_LABELS-1] = {};
+				struct promex_metric metric;
+
+				px = ctx->px;
+
+				labels[0].name  = ist("proxy");
+				labels[0].value = ist2(px->id, strlen(px->id));
+
+				labels[1].name  = ist("mod");
+				labels[1].value = ist2(ctx->mod->name, strlen(ctx->mod->name));
+
+				/* skip the disabled proxies, global frontend and non-networked ones */
+				if ((px->flags & PR_FL_DISABLED) || px->uuid <= 0 || !(px->cap & PR_CAP_BE))
+					goto next_px2;
+
+				counters = EXTRA_COUNTERS_GET(px->extra_counters_be, ctx->mod);
+				if (!ctx->mod->fill_stats(counters, stats + ctx->field_num, &ctx->mod_field_num))
+					return -1;
+
+				val = stats[ctx->field_num + ctx->mod_field_num];
+				metric.type = ((val.type == FN_GAUGE) ? PROMEX_MT_GAUGE : PROMEX_MT_COUNTER);
+
+				if (!promex_dump_metric(appctx, htx, prefix,
+							ist2(ctx->mod->stats[ctx->mod_field_num].name, strlen(ctx->mod->stats[ctx->mod_field_num].name)),
+							ist2(ctx->mod->stats[ctx->mod_field_num].desc, strlen(ctx->mod->stats[ctx->mod_field_num].desc)),
+							&metric, &val, labels, &out, max))
+					goto full;
+
+			next_px2:
+				ctx->px = px->next;
+			}
+
+			ctx->flags |= PROMEX_FL_METRIC_HDR;
+			ctx->px = proxies_list;
+		}
+
+		ctx->field_num += ctx->mod->stats_count;
+		ctx->mod_field_num = 0;
+	}
+
   end:
 	if (out.len) {
 		if (!htx_add_data_atonce(htx, out))