From cfffa01f73a598d88e06de58553dddcb2bf1e901 Mon Sep 17 00:00:00 2001
From: Nick <32660358+dontcrash@users.noreply.github.com>
Date: Fri, 25 Jul 2025 20:09:16 +0930
Subject: [PATCH] Add random option

---
 client/src/__locales/en.json              | 2 ++
 client/src/helpers/constants.ts           | 1 +
 internal/dnsforward/http.go               | 6 ++++++
 internal/dnsforward/http_internal_test.go | 8 ++++++++
 internal/dnsforward/upstreams.go          | 2 ++
 openapi/next.yaml                         | 3 +++
 6 files changed, 22 insertions(+)

diff --git a/client/src/__locales/en.json b/client/src/__locales/en.json
index e8e17250baf..5ec8d5acbb3 100644
--- a/client/src/__locales/en.json
+++ b/client/src/__locales/en.json
@@ -7,6 +7,8 @@
     "parallel_requests": "Parallel requests",
     "load_balancing": "Load-balancing",
     "load_balancing_desc": "Query one upstream server at a time.<br/>AdGuard Home uses a weighted random algorithm to select servers with the lowest number of failed lookups and the lowest average lookup time.",
+    "random": "Random",
+    "random_desc": "Query a random upstream server for every new query.",
     "bootstrap_dns": "Bootstrap DNS servers",
     "bootstrap_dns_desc": "IP addresses of DNS servers used to resolve IP addresses of the DoH/DoT resolvers you specify as upstreams. Comments are not permitted.",
     "fallback_dns_title": "Fallback DNS servers",
diff --git a/client/src/helpers/constants.ts b/client/src/helpers/constants.ts
index d4e7c940954..8608f432cd4 100644
--- a/client/src/helpers/constants.ts
+++ b/client/src/helpers/constants.ts
@@ -392,6 +392,7 @@ export const DNS_REQUEST_OPTIONS = {
     PARALLEL: 'parallel',
     FASTEST_ADDR: 'fastest_addr',
     LOAD_BALANCING: 'load_balance',
+    RANDOM: 'random',
 };
 
 export const DHCP_FORM_NAMES = {
diff --git a/internal/dnsforward/http.go b/internal/dnsforward/http.go
index 59f3fde8527..dab29a926a2 100644
--- a/internal/dnsforward/http.go
+++ b/internal/dnsforward/http.go
@@ -136,6 +136,7 @@ const (
 	jsonUpstreamModeLoadBalance jsonUpstreamMode = "load_balance"
 	jsonUpstreamModeParallel    jsonUpstreamMode = "parallel"
 	jsonUpstreamModeFastestAddr jsonUpstreamMode = "fastest_addr"
+	jsonUpstreamModeRandom      jsonUpstreamMode = "random"
 )
 
 func (s *Server) getDNSConfig() (c *jsonDNSConfig) {
@@ -180,6 +181,8 @@ func (s *Server) getDNSConfig() (c *jsonDNSConfig) {
 		upstreamMode = jsonUpstreamModeParallel
 	case UpstreamModeFastestAddr:
 		upstreamMode = jsonUpstreamModeFastestAddr
+	case UpstreamModeRandom:
+		upstreamMode = jsonUpstreamModeRandom
 	}
 
 	defPTRUps, err := s.defaultLocalPTRUpstreams()
@@ -265,6 +268,7 @@ func (req *jsonDNSConfig) checkUpstreamMode() (err error) {
 		jsonUpstreamModeLoadBalance,
 		jsonUpstreamModeParallel,
 		jsonUpstreamModeFastestAddr:
+		jsonUpstreamModeRandom:
 		return nil
 	default:
 		return fmt.Errorf("upstream_mode: incorrect value %q", um)
@@ -563,6 +567,8 @@ func mustParseUpstreamMode(mode jsonUpstreamMode) (um UpstreamMode) {
 		return UpstreamModeParallel
 	case jsonUpstreamModeFastestAddr:
 		return UpstreamModeFastestAddr
+	case jsonUpstreamModeRandom:
+		return UpstreamModeRandom
 	default:
 		// Should never happen, since the value should be validated.
 		panic(fmt.Errorf("unexpected upstream mode: %q", mode))
diff --git a/internal/dnsforward/http_internal_test.go b/internal/dnsforward/http_internal_test.go
index f57783c7d05..80ae6ced9d4 100644
--- a/internal/dnsforward/http_internal_test.go
+++ b/internal/dnsforward/http_internal_test.go
@@ -123,6 +123,14 @@ func TestDNSForwardHTTP_handleGetConfig(t *testing.T) {
 			return conf
 		},
 		name: "parallel",
+	}, {
+		conf: func() ServerConfig {
+			conf := defaultConf
+			conf.UpstreamMode = UpstreamModeRandom
+
+			return conf
+		},
+		name: "random",
 	}}
 
 	var data map[string]json.RawMessage
diff --git a/internal/dnsforward/upstreams.go b/internal/dnsforward/upstreams.go
index 618601bd1bc..03a7923d4cb 100644
--- a/internal/dnsforward/upstreams.go
+++ b/internal/dnsforward/upstreams.go
@@ -137,6 +137,8 @@ func setProxyUpstreamMode(
 	switch upstreamMode {
 	case UpstreamModeParallel:
 		conf.UpstreamMode = proxy.UpstreamModeParallel
+	case UpstreamModeRandom:
+		conf.UpstreamMode = proxy.UpstreamModeRandom
 	case UpstreamModeFastestAddr:
 		conf.UpstreamMode = proxy.UpstreamModeFastestAddr
 		conf.FastestPingTimeout = fastestTimeout
diff --git a/openapi/next.yaml b/openapi/next.yaml
index c9fdee12b7e..011ca4bf32d 100644
--- a/openapi/next.yaml
+++ b/openapi/next.yaml
@@ -2510,10 +2510,13 @@
 
          *  `parallel`: Use parallel requests to speed up resolving by
              simultaneously querying all upstream servers.
+
+        *  `random`: Query a random upstream server for every new query.
       'enum':
       - 'fastest'
       - 'load_balancing'
       - 'parallel'
+      - 'random'
       'type': 'string'
 
     'ErrorCode':