From fe7e3acbca3a0b9b3e46d7ffed3ca9e45eed97f8 Mon Sep 17 00:00:00 2001
From: Michael Quigley <michael@quigley.com>
Date: Thu, 21 Jul 2022 15:26:44 -0400
Subject: [PATCH] more proxy debugging

---
 http/http.go    | 14 ++++++++++++--
 proxy/proxy.go  | 24 ++++++++++++++++--------
 util/headers.go | 29 +++++++++++++++++++++++++++++
 3 files changed, 57 insertions(+), 10 deletions(-)
 create mode 100644 util/headers.go

diff --git a/http/http.go b/http/http.go
index ae1296d8..1511fc55 100644
--- a/http/http.go
+++ b/http/http.go
@@ -2,6 +2,7 @@ package http
 
 import (
 	"fmt"
+	"github.com/openziti-test-kitchen/zrok/util"
 	"github.com/openziti/sdk-golang/ziti"
 	"github.com/openziti/sdk-golang/ziti/config"
 	"github.com/pkg/errors"
@@ -35,24 +36,33 @@ func Run(cfg *Config) error {
 type handler struct{}
 
 func (self *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-	logrus.Infof("handling request from [%v]", r.RemoteAddr)
+	logrus.Warnf("handling request from [%v]", r.RemoteAddr)
 
 	r.Host = "localhost:3000"
 	r.URL.Host = "localhost:3000"
 	r.URL.Scheme = "http"
 	r.RequestURI = ""
+	logrus.Info(util.DumpHeaders(r.Header, true))
 
+	logrus.Infof("forwarding to: %v [%v]", r.Method, r.URL)
 	rr, err := http.DefaultClient.Do(r)
 	if err != nil {
 		w.WriteHeader(http.StatusInternalServerError)
 		_, _ = fmt.Fprint(w, err)
 		return
 	}
+	w.WriteHeader(rr.StatusCode)
+	logrus.Infof("response: %v", rr.Status)
 
+	// forward headers
 	for k, v := range rr.Header {
-		w.Header().Add(k, v[0])
+		for _, vi := range v {
+			w.Header().Add(k, vi)
+		}
 	}
+	logrus.Info(util.DumpHeaders(w.Header(), false))
 
+	// copy body
 	n, err := io.Copy(w, rr.Body)
 	if err != nil {
 		w.WriteHeader(http.StatusInternalServerError)
diff --git a/proxy/proxy.go b/proxy/proxy.go
index 9986015f..c8323fa6 100644
--- a/proxy/proxy.go
+++ b/proxy/proxy.go
@@ -31,29 +31,37 @@ type handler struct {
 }
 
 func (self *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-	logrus.Infof("handling request from [%v]", r.RemoteAddr)
+	logrus.Warnf("handling request from [%v]", r.RemoteAddr)
 
-	zDialCtx := util.ZitiDialContext{Context: self.zCtx}
-	zTransport := http.DefaultTransport.(*http.Transport).Clone()
-	zTransport.DialContext = zDialCtx.Dial
-	client := &http.Client{Transport: zTransport}
 	r.Host = "zrok"
 	r.URL.Host = "zrok"
 	r.URL.Scheme = "http"
 	r.RequestURI = ""
-	logrus.Warnf("request: %v", r)
+	logrus.Info(util.DumpHeaders(r.Header, true))
 
-	rr, err := client.Do(r)
+	logrus.Infof("forwarding to: %v [%v]", r.Method, r.URL)
+	zDialCtx := util.ZitiDialContext{Context: self.zCtx}
+	zTransport := http.DefaultTransport.(*http.Transport).Clone()
+	zTransport.DialContext = zDialCtx.Dial
+	zClient := &http.Client{Transport: zTransport}
+	rr, err := zClient.Do(r)
 	if err != nil {
 		w.WriteHeader(http.StatusInternalServerError)
 		_, _ = fmt.Fprint(w, err)
 		return
 	}
+	w.WriteHeader(rr.StatusCode)
+	logrus.Infof("response: %v", rr.Status)
 
+	// forward headers
 	for k, v := range rr.Header {
-		w.Header().Add(k, v[0])
+		for _, vi := range v {
+			w.Header().Add(k, vi)
+		}
 	}
+	logrus.Info(util.DumpHeaders(w.Header(), false))
 
+	// copy body
 	n, err := io.Copy(w, rr.Body)
 	if err != nil {
 		panic(err)
diff --git a/util/headers.go b/util/headers.go
new file mode 100644
index 00000000..4482520e
--- /dev/null
+++ b/util/headers.go
@@ -0,0 +1,29 @@
+package util
+
+import (
+	"fmt"
+	"net/http"
+	"sort"
+)
+
+func DumpHeaders(headers http.Header, in bool) string {
+	out := "headers {\n"
+	keys := make([]string, len(headers))
+	i := 0
+	for k, _ := range headers {
+		keys[i] = k
+		i++
+	}
+	sort.Strings(keys)
+	for _, k := range keys {
+		for _, v := range headers[k] {
+			indicator := "->"
+			if !in {
+				indicator = "<-"
+			}
+			out += fmt.Sprintf("\t%v %v: %v\n", indicator, k, v)
+		}
+	}
+	out += "}"
+	return out
+}