From: Michael Tremer <michael.tremer@ipfire.org>
Date: Fri, 10 Jul 2026 11:13:19 +0000 (+0000)
Subject: sources: knot-resolver: Connect to socket instead of kresctl
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9eca7ff2e5b2f69cfaf40e3e609c53f8eff11bf5;p=telemetry.git

sources: knot-resolver: Connect to socket instead of kresctl

This has significantly less overhead than calling the rather slow Python
command line tool.

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/daemon/sources/knot-resolver.c b/src/daemon/sources/knot-resolver.c
index 2d67892..e0e758d 100644
--- a/src/daemon/sources/knot-resolver.c
+++ b/src/daemon/sources/knot-resolver.c
@@ -23,8 +23,8 @@
 #include <errno.h>
 #include <limits.h>
 
-#include "../command.h"
 #include "../ctx.h"
+#include "../request.h"
 #include "../source.h"
 #include "../string.h"
 #include "knot-resolver.h"
@@ -159,14 +159,14 @@ static int knot_resolver_parse_metrics(td_ctx* ctx,
 	return 0;
 }
 
-static int knot_resolver_on_success(td_ctx* ctx, td_file* stdout, void* data) {
+static int knot_resolver_on_success(td_ctx* ctx, td_file* output, void* data) {
 	sd_json_variant* json = NULL;
 	td_metrics* metrics = NULL;
 	td_source* source = data;
 	int r;
 
 	// Parse the output as JSON
-	r = td_file_parse_json(stdout, &json, 0);
+	r = td_file_parse_json(output, &json, 0);
 	if (r < 0)
 		goto ERROR;
 
@@ -193,12 +193,35 @@ ERROR:
 }
 
 static int knot_resolver_heartbeat(td_ctx* ctx, td_source* source) {
-	// Run kresctl to fetch metrics
-	const char* argv[] = {
-		"kresctl", "metrics", NULL,
-	};
+	td_request* request = NULL;
+	int r;
+
+	// Create a new request
+	r = td_source_create_request(source, &request);
+	if (r < 0)
+		goto ERROR;
+
+	// Set the URL
+	r = td_request_set_url(request, "http://localhost/metrics/json");
+	if (r < 0)
+		goto ERROR;
 
-	return td_source_run_command(source, NULL, argv, knot_resolver_on_success, source);
+	// Set the socket
+	r = td_request_set_socket(request, "/var/run/knot-resolver/kres-api.sock");
+	if (r < 0)
+		goto ERROR;
+
+	// Configure the success callback
+	td_request_on_success(request, knot_resolver_on_success, source);
+
+	// Launch the request
+	r = td_request_launch(request);
+
+ERROR:
+	if (request)
+		td_request_unref(request);
+
+	return r;
 }
 
 const td_source_impl knot_resolver_source = {