From 5ab977feb52cea8c01ea08a3100f267e59352b47 Mon Sep 17 00:00:00 2001
From: Paul Lorenz <paul.lorenz@netfoundry.io>
Date: Wed, 10 Mar 2021 20:13:44 -0500
Subject: [PATCH] Don't require listener address, as not every xgress impl
 needs one

---
 router/config.go                        |  4 ----
 router/router.go                        | 28 ++++++++++++++-----------
 router/xgress_proxy/listener.go         |  4 ++++
 router/xgress_proxy_udp/listener.go     |  4 ++++
 router/xgress_transport/listener.go     |  4 ++++
 router/xgress_transport_udp/listener.go |  4 ++++
 6 files changed, 32 insertions(+), 16 deletions(-)

diff --git a/router/config.go b/router/config.go
index 702296a08..b56ed4439 100644
--- a/router/config.go
+++ b/router/config.go
@@ -297,10 +297,6 @@ func LoadConfig(path string) (*Config, error) {
 					if !found {
 						return nil, fmt.Errorf("[listener] must provide [binding] (%v)", submap)
 					}
-					_, found = submap["address"]
-					if !found {
-						return nil, fmt.Errorf("[listener] must provide [address] (%v)", submap)
-					}
 					cfg.Listeners = append(cfg.Listeners, listenerBinding{name: binding, options: submap})
 				}
 			}
diff --git a/router/router.go b/router/router.go
index 7eb93aa72..c05a202d0 100644
--- a/router/router.go
+++ b/router/router.go
@@ -272,19 +272,23 @@ func (self *Router) startXgressListeners() {
 			logrus.Fatalf("error creating xgress listener [%s] (%v)", binding.name, err)
 		}
 		self.xgressListeners = append(self.xgressListeners, listener)
-		if address, found := binding.options["address"]; found {
-			err = listener.Listen(address.(string),
-				handler_xgress.NewBindHandler(
-					handler_xgress.NewReceiveHandler(self.forwarder),
-					handler_xgress.NewCloseHandler(self, self.forwarder),
-					self.forwarder,
-				),
-			)
-			if err != nil {
-				logrus.Fatalf("error listening [%s] (%v)", binding.name, err)
-			}
-			logrus.Infof("created xgress listener [%s] at [%s]", binding.name, address)
+
+		var address string
+		if addressVal, found := binding.options["address"]; found {
+			address = addressVal.(string)
 		}
+
+		err = listener.Listen(address,
+			handler_xgress.NewBindHandler(
+				handler_xgress.NewReceiveHandler(self.forwarder),
+				handler_xgress.NewCloseHandler(self, self.forwarder),
+				self.forwarder,
+			),
+		)
+		if err != nil {
+			logrus.Fatalf("error listening [%s] (%v)", binding.name, err)
+		}
+		logrus.Infof("created xgress listener [%s] at [%s]", binding.name, address)
 	}
 }
 
diff --git a/router/xgress_proxy/listener.go b/router/xgress_proxy/listener.go
index 50ef89e5b..a9a6dd028 100644
--- a/router/xgress_proxy/listener.go
+++ b/router/xgress_proxy/listener.go
@@ -17,6 +17,7 @@
 package xgress_proxy
 
 import (
+	"errors"
 	"fmt"
 	"github.com/michaelquigley/pfxlog"
 	"github.com/openziti/fabric/router/xgress"
@@ -36,6 +37,9 @@ func newListener(id *identity.TokenId, ctrl xgress.CtrlChannel, options *xgress.
 }
 
 func (listener *listener) Listen(address string, bindHandler xgress.BindHandler) error {
+	if address == "" {
+		return errors.New("address must be specified for proxy listeners")
+	}
 	txAddress, err := transport.ParseAddress(address)
 	if err != nil {
 		return fmt.Errorf("cannot listen on invalid address [%s] (%s)", address, err)
diff --git a/router/xgress_proxy_udp/listener.go b/router/xgress_proxy_udp/listener.go
index ceb1e93fc..b0828da85 100644
--- a/router/xgress_proxy_udp/listener.go
+++ b/router/xgress_proxy_udp/listener.go
@@ -21,12 +21,16 @@ import (
 	"github.com/openziti/fabric/router/xgress"
 	"github.com/openziti/fabric/router/xgress_udp"
 	"github.com/openziti/foundation/util/info"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	"net"
 	"time"
 )
 
 func (l *listener) Listen(address string, bindHandler xgress.BindHandler) error {
+	if address == "" {
+		return errors.New("address must be specified for proxy_udp listeners")
+	}
 	l.address = address
 	l.bindHandler = bindHandler
 
diff --git a/router/xgress_transport/listener.go b/router/xgress_transport/listener.go
index b50af2b1f..7036ab9b4 100644
--- a/router/xgress_transport/listener.go
+++ b/router/xgress_transport/listener.go
@@ -17,6 +17,7 @@
 package xgress_transport
 
 import (
+	"errors"
 	"fmt"
 	"github.com/michaelquigley/pfxlog"
 	"github.com/openziti/fabric/router/xgress"
@@ -43,6 +44,9 @@ func newListener(id *identity.TokenId, ctrl xgress.CtrlChannel, options *xgress.
 }
 
 func (listener *listener) Listen(address string, bindHandler xgress.BindHandler) error {
+	if address == "" {
+		return errors.New("address must be specified for transport listeners")
+	}
 	txAddress, err := transport.ParseAddress(address)
 	if err != nil {
 		return fmt.Errorf("cannot listen on invalid address [%s] (%s)", address, err)
diff --git a/router/xgress_transport_udp/listener.go b/router/xgress_transport_udp/listener.go
index 5878a35b0..20a673fbc 100644
--- a/router/xgress_transport_udp/listener.go
+++ b/router/xgress_transport_udp/listener.go
@@ -17,6 +17,7 @@
 package xgress_transport_udp
 
 import (
+	"errors"
 	"fmt"
 	"github.com/michaelquigley/pfxlog"
 	"github.com/openziti/fabric/router/xgress"
@@ -28,6 +29,9 @@ import (
 )
 
 func (l *listener) Listen(address string, bindHandler xgress.BindHandler) error {
+	if address == "" {
+		return errors.New("address must be specified for transport_udp listeners")
+	}
 	l.address = address
 	l.bindHandler = bindHandler