the top Route header should be optionally kept #16

main.go

@@ -2,18 +2,20 @@ package main
 
 import (
 	"fmt"
-	"github.com/urfave/cli/v2"
-	"go.uber.org/zap"
-	"go.uber.org/zap/zapcore"
-	"gopkg.in/natefinch/lumberjack.v2"
-	"gopkg.in/yaml.v3"
 	"io"
 	"net/http"
 	_ "net/http/pprof"
 	"os"
+	"slices"
 	"strconv"
 	"strings"
 	"time"
+
+	"github.com/urfave/cli/v2"
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+	"gopkg.in/natefinch/lumberjack.v2"
+	"gopkg.in/yaml.v3"
 )
 
 type HostIp struct {
@@ -22,9 +24,10 @@ type HostIp struct {
 }
 
 type ProxyConfig struct {
-	Name          string
-	DialogTimeout int `yaml:"dialogTimeout,omitempty"`
-	Listens       []struct {
+	Name             string
+	DialogTimeout    int    `yaml:"dialogTimeout,omitempty"`
+	KeepNextHopRoute string `yaml:"keepNextHopRoute,omitempty"`
+	Listens          []struct {
 		Address    string
 		UDPPort    int      `yaml:"udp-port,omitempty"`
 		TCPPort    int      `yaml:"tcp-port,omitempty"`
@@ -111,6 +114,16 @@ func loadConfig(fileName string) (*ProxiesConfigure, error) {
 
 }
 
+func toKeepNextHopRoute(s string) bool {
+
+	possibleTrueValues := []string{"true", "yes", "1", "on", "t", "y"}
+
+	if s == "" {
+		s = os.Getenv("KEEP_NEXT_HOP_ROUTE")
+	}
+	return slices.Contains(possibleTrueValues, strings.ToLower(s))
+}
+
 func startProxies(c *cli.Context) error {
 	config, err := loadConfig(c.String("config"))
 	if err != nil {
@@ -158,7 +171,7 @@ func startProxy(config ProxyConfig, preConfigRoute *PreConfigRoute, resolver *Pr
 	if dialogTimeout <= 0 {
 		dialogTimeout = getDefaultDialogTimeout()
 	}
-	proxy := NewProxy(config.Name, int64(dialogTimeout), preConfigRoute, resolver, selfLearnRoute)
+	proxy := NewProxy(config.Name, int64(dialogTimeout), toKeepNextHopRoute(config.KeepNextHopRoute), preConfigRoute, resolver, selfLearnRoute)
 	for _, listen := range config.Listens {
 		item, err := NewProxyItem(listen.Address,
 			listen.UDPPort,

proxy.go

@@ -117,6 +117,7 @@ func (p *MyName) isMyMessage(msg *Message) bool {
 
 type Proxy struct {
 	myName               *MyName
+	keepNextHopRoute     bool
 	preConfigRoute       *PreConfigRoute
 	resolver             *PreConfigHostResolver
 	items                []*ProxyItem
@@ -131,10 +132,12 @@ type Proxy struct {
 
 func NewProxy(name string,
 	dialogExpire int64,
+	keepNextHopRoute bool,
 	preConfigRoute *PreConfigRoute,
 	resolver *PreConfigHostResolver,
 	selfLearnRoute *SelfLearnRoute) *Proxy {
 	proxy := &Proxy{myName: NewMyName(name),
+		keepNextHopRoute:     keepNextHopRoute,
 		preConfigRoute:       preConfigRoute,
 		resolver:             resolver,
 		items:                make([]*ProxyItem, 0),
@@ -343,11 +346,11 @@ func (p *Proxy) HandleMessage(msg *Message) {
 		if err == nil {
 			zap.L().Info("Get next hop", zap.String("host", host), zap.Int("port", port), zap.String("transport", transport))
 			serverTrans, ok := p.selfLearnRoute.GetRoute(host)
+
 			if ok {
 				p.addVia(msg, serverTrans)
 				p.addRecordRoute(msg, serverTrans)
 			}
-
 			p.sendMessage(host, port, transport, msg)
 		} else if p.myName.isMyMessage(msg) {
 			zap.L().Info("it is my request")
@@ -539,7 +542,9 @@ func (P *Proxy) getNextRequestHopByRoute(msg *Message) (host string, port int, t
 	if err != nil {
 		return
 	}
-	msg.PopRoute()
+	if !P.keepNextHopRoute {
+		msg.PopRoute()
+	}
 	addr := routeParam.GetAddress().GetAddress()
 	if addr.IsSIPURI() {
 		sipUri, _ := addr.GetSIPURI()

via.go

@@ -61,9 +61,9 @@ func (v *Via) String() string {
 }
 
 func (vp *ViaParam) SetParam(name string, value string) {
-	for _, param := range vp.Params {
+	for key, param := range vp.Params {
 		if param.Key == name {
-			param.Value = value
+			vp.Params[key].Value = value
 			return
 		}
 	}