Observatory related fixes (#788)

* fix:observatory not supported by multi-json

* Fix: observatory starts with empty config & fails to close (#957)

* Update strategy_leastping.go (#1019)

* add custom probe URL support for observatory

* add custom probe interval for observer

* apply coding style

* Fix: observatory log & JSON config(#1211)

Co-authored-by: ihotte <ihotte@yeah.net>

* Change default probe url from api.v2fly.org to www.google.com

* Cherry-pick missing code from branch 'dev-advloadblancer-2'

Co-authored-by: Shelikhoo <xiaokangwang@outlook.com>
Co-authored-by: Loyalsoldier <10487845+Loyalsoldier@users.noreply.github.com>
Co-authored-by: fanyiguan <52657276+fanyiguang@users.noreply.github.com>
Co-authored-by: ihotte <3087168217@qq.com>
Co-authored-by: ihotte <ihotte@yeah.net>

infra/conf/api.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/xtls/xray-core/app/commander"
 	loggerservice "github.com/xtls/xray-core/app/log/command"
+	observatoryservice "github.com/xtls/xray-core/app/observatory/command"
 	handlerservice "github.com/xtls/xray-core/app/proxyman/command"
 	statsservice "github.com/xtls/xray-core/app/stats/command"
 	"github.com/xtls/xray-core/common/serial"
@@ -31,6 +32,8 @@ func (c *APIConfig) Build() (*commander.Config, error) {
 			services = append(services, serial.ToTypedMessage(&loggerservice.Config{}))
 		case "statsservice":
 			services = append(services, serial.ToTypedMessage(&statsservice.Config{}))
+		case "observatoryservice":
+			services = append(services, serial.ToTypedMessage(&observatoryservice.Config{}))
 		}
 	}
 

infra/conf/cfgcommon/duration/duration.go

@@ -0,0 +1,33 @@
+package duration
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+type Duration int64
+
+func (d *Duration) MarshalJSON() ([]byte, error) {
+	dr := time.Duration(*d)
+	return json.Marshal(dr.String())
+}
+
+func (d *Duration) UnmarshalJSON(b []byte) error {
+	var v interface{}
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+	switch value := v.(type) {
+	case string:
+		var err error
+		dr, err := time.ParseDuration(value)
+		if err != nil {
+			return err
+		}
+		*d = Duration(dr)
+		return nil
+	default:
+		return fmt.Errorf("invalid duration: %v", v)
+	}
+}

infra/conf/cfgcommon/duration/duration_test.go

@@ -0,0 +1,33 @@
+package duration_test
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/xtls/xray-core/infra/conf/cfgcommon/duration"
+)
+
+type testWithDuration struct {
+	Duration duration.Duration
+}
+
+func TestDurationJSON(t *testing.T) {
+	expected := &testWithDuration{
+		Duration: duration.Duration(time.Hour),
+	}
+	data, err := json.Marshal(expected)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	actual := &testWithDuration{}
+	err = json.Unmarshal(data, &actual)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	if actual.Duration != expected.Duration {
+		t.Errorf("expected: %s, actual: %s", time.Duration(expected.Duration), time.Duration(actual.Duration))
+	}
+}

infra/conf/observatory.go

@@ -2,13 +2,17 @@ package conf
 
 import (
 	"github.com/golang/protobuf/proto"
+	
 	"github.com/xtls/xray-core/app/observatory"
+	"github.com/xtls/xray-core/infra/conf/cfgcommon/duration"
 )
 
 type ObservatoryConfig struct {
-	SubjectSelector []string `json:"subjectSelector"`
+	SubjectSelector []string          `json:"subjectSelector"`
+	ProbeURL        string            `json:"probeURL"`
+	ProbeInterval   duration.Duration `json:"probeInterval"`
 }
 
-func (o ObservatoryConfig) Build() (proto.Message, error) {
-	return &observatory.Config{SubjectSelector: o.SubjectSelector}, nil
+func (o *ObservatoryConfig) Build() (proto.Message, error) {
+	return &observatory.Config{SubjectSelector: o.SubjectSelector, ProbeUrl: o.ProbeURL, ProbeInterval: int64(o.ProbeInterval)}, nil
 }

infra/conf/router.go

@@ -18,9 +18,16 @@ type RouterRulesConfig struct {
 	DomainStrategy string            `json:"domainStrategy"`
 }
 
+// StrategyConfig represents a strategy config
+type StrategyConfig struct {
+	Type     string           `json:"type"`
+	Settings *json.RawMessage `json:"settings"`
+}
+
 type BalancingRule struct {
-	Tag       string     `json:"tag"`
-	Selectors StringList `json:"selector"`
+	Tag       string         `json:"tag"`
+	Selectors StringList     `json:"selector"`
+	Strategy  StrategyConfig `json:"strategy"`
 }
 
 func (r *BalancingRule) Build() (*router.BalancingRule, error) {
@@ -31,9 +38,20 @@ func (r *BalancingRule) Build() (*router.BalancingRule, error) {
 		return nil, newError("empty selector list")
 	}
 
+	var strategy string
+	switch strings.ToLower(r.Strategy.Type) {
+	case strategyRandom, "":
+		strategy = strategyRandom
+	case strategyLeastPing:
+		strategy = "leastPing"
+	default:
+		return nil, newError("unknown balancing strategy: " + r.Strategy.Type)
+	}
+
 	return &router.BalancingRule{
 		Tag:              r.Tag,
 		OutboundSelector: []string(r.Selectors),
+		Strategy:         strategy,
 	}, nil
 }
 

infra/conf/router_strategy.go

@@ -0,0 +1,6 @@
+package conf
+
+const (
+	strategyRandom    string = "random"
+	strategyLeastPing string = "leastping"
+)

infra/conf/router_test.go

@@ -107,6 +107,7 @@ func TestRouterConfig(t *testing.T) {
 					{
 						Tag:              "b1",
 						OutboundSelector: []string{"test"},
+						Strategy:         "random",
 					},
 				},
 				Rule: []*router.RoutingRule{

infra/conf/xray.go

@@ -464,6 +464,10 @@ func (c *Config) Override(o *Config, fn string) {
 		c.FakeDNS = o.FakeDNS
 	}
 
+	if o.Observatory != nil {
+		c.Observatory = o.Observatory
+	}
+
 	// deprecated attrs... keep them for now
 	if o.InboundConfig != nil {
 		c.InboundConfig = o.InboundConfig