API - Add | Remove Routing Rules (#3189)

* add RuleTag to routing rules

* add router pb commands

* add and remove routing rules api

* cleanup

* fix

* improve error msg

* add append flag
apply balancer config

app/router/router.go

@@ -4,8 +4,10 @@ package router
 
 import (
 	"context"
+	sync "sync"
 
 	"github.com/xtls/xray-core/common"
+	"github.com/xtls/xray-core/common/serial"
 	"github.com/xtls/xray-core/core"
 	"github.com/xtls/xray-core/features/dns"
 	"github.com/xtls/xray-core/features/outbound"
@@ -19,6 +21,11 @@ type Router struct {
 	rules          []*Rule
 	balancers      map[string]*Balancer
 	dns            dns.Client
+
+	ctx        context.Context
+	ohm        outbound.Manager
+	dispatcher routing.Dispatcher
+	mu         sync.Mutex
 }
 
 // Route is an implementation of routing.Route.
@@ -32,6 +39,9 @@ type Route struct {
 func (r *Router) Init(ctx context.Context, config *Config, d dns.Client, ohm outbound.Manager, dispatcher routing.Dispatcher) error {
 	r.domainStrategy = config.DomainStrategy
 	r.dns = d
+	r.ctx = ctx
+	r.ohm = ohm
+	r.dispatcher = dispatcher
 
 	r.balancers = make(map[string]*Balancer, len(config.BalancingRule))
 	for _, rule := range config.BalancingRule {
@@ -52,6 +62,7 @@ func (r *Router) Init(ctx context.Context, config *Config, d dns.Client, ohm out
 		rr := &Rule{
 			Condition: cond,
 			Tag:       rule.GetTag(),
+			RuleTag:   rule.GetRuleTag(),
 		}
 		btag := rule.GetBalancingTag()
 		if len(btag) > 0 {
@@ -80,6 +91,96 @@ func (r *Router) PickRoute(ctx routing.Context) (routing.Route, error) {
 	return &Route{Context: ctx, outboundTag: tag}, nil
 }
 
+// AddRule implements routing.Router.
+func (r *Router) AddRule(config *serial.TypedMessage, shouldAppend bool) error {
+
+	inst, err := config.GetInstance()
+	if err != nil {
+		return err
+	}
+	if c, ok := inst.(*Config); ok {
+		return r.ReloadRules(c, shouldAppend)
+	}
+	return newError("AddRule: config type error")
+}
+
+func (r *Router) ReloadRules(config *Config, shouldAppend bool) error {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	if !shouldAppend {
+		r.balancers = make(map[string]*Balancer, len(config.BalancingRule))
+		r.rules = make([]*Rule, 0, len(config.Rule))
+	}
+	for _, rule := range config.BalancingRule {
+		_, found := r.balancers[rule.Tag]
+		if found {
+			return newError("duplicate balancer tag")
+		}
+		balancer, err := rule.Build(r.ohm, r.dispatcher)
+		if err != nil {
+			return err
+		}
+		balancer.InjectContext(r.ctx)
+		r.balancers[rule.Tag] = balancer
+	}
+
+	for _, rule := range config.Rule {
+		if r.RuleExists(rule.GetRuleTag()) {
+			return newError("duplicate ruleTag ", rule.GetRuleTag())
+		}
+		cond, err := rule.BuildCondition()
+		if err != nil {
+			return err
+		}
+		rr := &Rule{
+			Condition: cond,
+			Tag:       rule.GetTag(),
+			RuleTag:   rule.GetRuleTag(),
+		}
+		btag := rule.GetBalancingTag()
+		if len(btag) > 0 {
+			brule, found := r.balancers[btag]
+			if !found {
+				return newError("balancer ", btag, " not found")
+			}
+			rr.Balancer = brule
+		}
+		r.rules = append(r.rules, rr)
+	}
+
+	return nil
+}
+
+func (r *Router) RuleExists(tag string) bool {
+	if tag != "" {
+		for _, rule := range r.rules {
+			if rule.RuleTag == tag {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// RemoveRule implements routing.Router.
+func (r *Router) RemoveRule(tag string) error {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	newRules := []*Rule{}
+	if tag != "" {
+		for _, rule := range r.rules {
+			if rule.RuleTag != tag {
+				newRules = append(newRules, rule)
+			}
+		}
+		r.rules = newRules
+		return nil
+	}
+	return newError("empty tag name!")
+
+}
 func (r *Router) pickRouteInternal(ctx routing.Context) (*Rule, routing.Context, error) {
 	// SkipDNSResolve is set from DNS module.
 	// the DOH remote server maybe a domain name,