Reimplement proxy using ReverseProxy

cmd/proxy/proxy.go

@@ -1,11 +1,11 @@
-// This is honestly terrible
+// This is honestly terrible. It only exists to replace the AWS S3 website hosting feature missing in minio
 package main
 
 import (
-	"io"
 	"log"
+	"net"
 	"net/http"
-	"net/url"
+	"net/http/httputil"
 	"os"
 	"strings"
 	"time"
@@ -16,7 +16,6 @@ import (
 var endpoint string
 var endpointSecure bool
 var behindProxy bool
-var client *http.Client
 
 func main() {
 	// Read configuration
@@ -24,23 +23,11 @@ func main() {
 	endpointSecure = os.Getenv("MINIO_ENDPOINT_SECURE") == "true"
 	behindProxy = os.Getenv("BEHIND_PROXY") == "true"
 
-	// Setup HTTP client
-	transport := &http.Transport{
-		MaxIdleConns:        4,
-		MaxIdleConnsPerHost: 4,
-		IdleConnTimeout:     30 * time.Second,
-		DisableCompression:  true,
-	}
-	client = &http.Client{
-		Transport: transport,
-		Timeout:   5 * time.Second,
-	}
-
 	server := &http.Server{
 		Addr:         ":80",
 		ReadTimeout:  5 * time.Second,
 		WriteTimeout: 10 * time.Second,
-		Handler:      http.HandlerFunc(handle),
+		Handler:      &httputil.ReverseProxy{Director: director},
 	}
 	err := server.ListenAndServe()
 	if err != nil {
@@ -48,44 +35,38 @@ func main() {
 	}
 }
 
-func handle(w http.ResponseWriter, r *http.Request) {
+func director(req *http.Request) {
 	// Validate host
-	if _, ok := dns.IsDomainName(r.Host); !ok {
-		w.WriteHeader(http.StatusBadRequest)
+	host, port, err := net.SplitHostPort(req.Host)
+	if err != nil {
+		// Assumption: IsDomainName will handle other cases
+		host = req.Host
+	}
+	if _, ok := dns.IsDomainName(host); !ok {
+		req.URL.Scheme = ""
 		return
 	}
 
 	// Rewrite URL
-	path := mapPath(r.URL.Path, r.Host)
-	url := &url.URL{
-		Scheme: "http",
-		Host:   endpoint,
-		Path:   path,
-	}
+	req.URL.Scheme = "http"
 	if endpointSecure {
-		url.Scheme = "https"
+		req.URL.Scheme = "https"
+	}
+	req.URL.Host = endpoint
+	req.URL.Path = mapPath(req.URL.Path, host)
+
+	if !behindProxy {
+		// Clear existing unsafe headers
+		req.Header.Del("Forwarded")
+		req.Header.Del("X-Forwarded-For")
+
+		// Unnecessary, but might as well
+		req.Header.Set("X-Forwarded-Proto", req.URL.Scheme)
+		req.Header.Set("X-Forwarded-Host", host)
+		req.Header.Set("X-Forwarded-Port", port)
 	}
 
-	// Update Forwarded headers
-	header := safeCloneHeader(r.Header)
-
-	// Create forwarded request
-	out := &http.Request{
-		URL:    url,
-		Header: header,
-	}
-
-	log.Println(out.URL)
-	resp, err := client.Do(out)
-	if err != nil {
-		w.WriteHeader(http.StatusInternalServerError)
-		log.Println(err)
-		return
-	}
-	defer resp.Body.Close()
-
-	w.WriteHeader(resp.StatusCode)
-	io.Copy(w, resp.Body)
+	log.Println(req.URL)
 }
 
 func mapPath(path, host string) string {
@@ -94,36 +75,3 @@ func mapPath(path, host string) string {
 	}
 	return "/" + host + path
 }
-
-// Further validation is required for this function
-func safeCloneHeader(h http.Header) http.Header {
-	clone := make(http.Header, 0)
-	for key, value := range h {
-		if !safeHeaderName(key) {
-			continue
-		}
-		for _, v := range value {
-			clone.Add(key, v)
-		}
-	}
-	return clone
-}
-
-// Comparisons in this function MUST be in canonical form
-func safeHeaderName(name string) bool {
-	if behindProxy {
-		if name == "X-Forwarded-For" {
-			return true
-		}
-		if name == "X-Forwarded-Host" {
-			return true
-		}
-		if name == "X-Forwarded-Proto" {
-			return true
-		}
-		if name == "Forwarded" {
-			return true
-		}
-	}
-	return false
-}

cmd/thumbnail/thumbnail.go

@@ -101,7 +101,6 @@ func update(w http.ResponseWriter, req *http.Request) {
 	}
 
 	wg.Wait()
-
 	// Check for errors
 	for _, op := range resizes {
 		if op.err != nil {
@@ -124,7 +123,6 @@ func update(w http.ResponseWriter, req *http.Request) {
 	}
 
 	wg.Wait()
-
 	// Check for errors
 	for _, op := range resizes {
 		if op.err != nil {