From 095ad06baac4bbc07131923ce8773f21a4afbbf7 Mon Sep 17 00:00:00 2001
From: hosswald <32925139+hosswald@users.noreply.github.com>
Date: Wed, 7 Sep 2022 15:20:03 +0200
Subject: [PATCH] add a sanitized version of the hostname (replace any
 character matching [^a-zA-Z0-9\-.] with underscore) fixes txn2/kubefwd#240

---
 pkg/fwdport/fwdport.go | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/pkg/fwdport/fwdport.go b/pkg/fwdport/fwdport.go
index a0837c2b..b31f5023 100644
--- a/pkg/fwdport/fwdport.go
+++ b/pkg/fwdport/fwdport.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"net"
 	"net/http"
+	"regexp"
 	"strconv"
 	"sync"
 	"time"
@@ -248,6 +249,13 @@ func (pfo *PortForwardOpts) addHost(host string) {
 
 	// add host to /etc/hosts
 	pfo.HostFile.Hosts.AddHost(pfo.LocalIp.String(), host)
+
+	// replace illegal characters with underscore and add another entry if this changes the hostname
+	hostnameIllegalChars := regexp.MustCompile(`[^a-zA-Z0-9\-.]`)
+	sanitizedHost := hostnameIllegalChars.ReplaceAllString(host, `_`)
+	if host != sanitizedHost {
+		pfo.addHost(sanitizedHost) //should recurse only once
+	}
 }
 
 // AddHosts adds hostname entries to /etc/hosts