feat: allow group override global node connectivity check

component/outbound/dialer/dialer.go

@@ -83,6 +83,10 @@ func NewDialer(dialer netproxy.Dialer, option *GlobalOption, iOption InstanceOpt
 	return d
 }
 
+func (d *Dialer) Clone() *Dialer {
+	return NewDialer(d.Dialer, d.GlobalOption, d.InstanceOption, d.property)
+}
+
 func (d *Dialer) Close() error {
 	d.cancel()
 	d.tickerMu.Lock()

config/config.go

@@ -89,6 +89,12 @@ type Group struct {
 	Filter           [][]*config_parser.Function `mapstructure:"filter" repeatable:""`
 	FilterAnnotation [][]*config_parser.Param    `mapstructure:"_"`
 	Policy           FunctionListOrString        `mapstructure:"policy" required:""`
+
+	TcpCheckUrl        []string      `mapstructure:"tcp_check_url"`
+	TcpCheckHttpMethod string        `mapstructure:"tcp_check_http_method"`
+	UdpCheckDns        []string      `mapstructure:"udp_check_dns"`
+	CheckInterval      time.Duration `mapstructure:"check_interval"`
+	CheckTolerance     time.Duration `mapstructure:"check_tolerance"`
 }
 
 type DnsRequestRouting struct {

config/desc.go

@@ -85,4 +85,9 @@ min: Select node by the latency of last check.
 min_avg10: Select node by the average of latencies of last 10 checks.
 min_moving_avg: Select node by the moving average of latencies of checks, which means more recent latencies have higher weight.
 `,
+	"tcp_check_url":         "Override global config.",
+	"tcp_check_http_method": "Override global config.",
+	"udp_check_dns":         "Override global config.",
+	"check_interval":        "Override global config.",
+	"check_tolerance":       "Override global config.",
 }

control/control_plane.go

@@ -323,6 +323,17 @@ func NewControlPlane(
 		if len(dialers) == 0 {
 			log.Infoln("\t<Empty>")
 		}
+		groupOption, err := ParseGroupOverrideOption(group, *global, log)
+		if err == nil && groupOption != nil {
+			newDialerSet := make([]*dialer.Dialer, 0)
+			for _, d := range dialers {
+				newDialer := d.Clone()
+				newDialer.GlobalOption = groupOption
+				newDialerSet = append(newDialerSet, newDialer)
+			}
+			log.Infof(`Group "%v"'s check option has been override.`, group.Name)
+			dialers = newDialerSet
+		}
 		// Create dialer group and append it to outbounds.
 		dialerGroup := outbound.NewDialerGroup(option, group.Name, dialers, annos, *policy,
 			core.outboundAliveChangeCallback(uint8(len(outbounds)), disableKernelAliveCallback))
@@ -515,6 +526,47 @@ func ParseFixedDomainTtl(ks []config.KeyableString) (map[string]int, error) {
 	return m, nil
 }
 
+func ParseGroupOverrideOption(group config.Group, global config.Global, log *logrus.Logger) (*dialer.GlobalOption, error) {
+	result := global
+	changed := false
+	if group.TcpCheckUrl != nil {
+		result.TcpCheckUrl = group.TcpCheckUrl
+		changed = true
+	}
+	if group.TcpCheckHttpMethod == "" {
+		result.TcpCheckHttpMethod = group.TcpCheckHttpMethod
+		changed = true
+	}
+	if group.UdpCheckDns != nil {
+		result.UdpCheckDns = group.UdpCheckDns
+		changed = true
+	}
+	if group.CheckInterval != 0 {
+		result.CheckInterval = group.CheckInterval
+		changed = true
+	}
+	if group.CheckTolerance != 0 {
+		result.CheckTolerance = group.CheckTolerance
+		changed = true
+	}
+	if changed {
+		option := dialer.GlobalOption{
+			ExtraOption: D.ExtraOption{
+				AllowInsecure:     global.AllowInsecure,
+				TlsImplementation: global.TlsImplementation,
+				UtlsImitate:       global.UtlsImitate},
+			Log:               log,
+			TcpCheckOptionRaw: dialer.TcpCheckOptionRaw{Raw: result.TcpCheckUrl, Log: log, ResolverNetwork: common.MagicNetwork("udp", global.SoMarkFromDae, global.Mptcp), Method: result.TcpCheckHttpMethod},
+			CheckDnsOptionRaw: dialer.CheckDnsOptionRaw{Raw: result.UdpCheckDns, ResolverNetwork: common.MagicNetwork("udp", global.SoMarkFromDae, global.Mptcp), Somark: global.SoMarkFromDae},
+			CheckInterval:     result.CheckInterval,
+			CheckTolerance:    result.CheckTolerance,
+			CheckDnsTcp:       true,
+		}
+		return &option, nil
+	}
+	return nil, nil
+}
+
 // EjectBpf will resect bpf from destroying life-cycle of control plane.
 func (c *ControlPlane) EjectBpf() *bpfObjects {
 	return c.core.EjectBpf()

example.dae

@@ -40,6 +40,7 @@ global {
     auto_config_kernel_parameter: true
 
     ##### Node connectivity check.
+    # These options, as defaults, are effective when no definition is given in the group.
 
     # Host of URL should have both IPv4 and IPv6 if you have double stack in local.
     # First is URL, others are IP addresses if given.
@@ -212,6 +213,12 @@ group {
 
         # Select the node with min average of the last 10 latencies from the group for every connection.
         policy: min_avg10
+
+        # Override tcp_check_url in global.
+        tcp_check_url: https://gstatic.com/generate_204
+
+        # This not override global tcp_check_http_method so it still will be "HEAD"
+        #tcp_check_http_method: GET
     }
 }