proxy: make http redirect server configurable (#105)

cmd/pomerium/main.go

@@ -113,17 +113,23 @@ func main() {
 		KeyFile:  mainOpts.KeyFile,
 	}
 
-	// redirect http to https
-	srv := &http.Server{
-		ReadTimeout:  5 * time.Second,
-		WriteTimeout: 5 * time.Second,
-		Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			w.Header().Set("Connection", "close")
-			url := fmt.Sprintf("https://%s%s", r.Host, r.URL.String())
-			http.Redirect(w, r, url, http.StatusMovedPermanently)
-		}),
+	if mainOpts.HTTPRedirectAddr != "" {
+		// stand up another http server that just redirect HTTP to HTTPS traffic
+		srv := &http.Server{
+			Addr:         mainOpts.HTTPRedirectAddr,
+			ReadTimeout:  5 * time.Second,
+			WriteTimeout: 5 * time.Second,
+			Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				w.Header().Set("Connection", "close")
+				url := fmt.Sprintf("https://%s%s", urlutil.StripPort(r.Host), r.URL.String())
+				http.Redirect(w, r, url, http.StatusMovedPermanently)
+			}),
+		}
+		log.Info().Str("Addr", mainOpts.HTTPRedirectAddr).Msg("cmd/pomerium: http redirect server started")
+		go func() { log.Fatal().Err(srv.ListenAndServe()).Msg("cmd/pomerium: http server") }()
+	} else {
+		log.Debug().Msg("cmd/pomerium: http redirect server not started")
 	}
-	go func() { log.Fatal().Err(srv.ListenAndServe()).Msg("cmd/pomerium: http server") }()
 
 	log.Fatal().Err(https.ListenAndServeTLS(httpOpts, topMux, grpcServer)).Msg("cmd/pomerium: https server")
 

cmd/pomerium/options.go

@@ -38,6 +38,11 @@ type Options struct {
 	// CertFile and KeyFile specifies the TLS certificates to use.
 	CertFile string `envconfig:"CERTIFICATE_FILE"`
 	KeyFile  string `envconfig:"CERTIFICATE_KEY_FILE"`
+
+	// HttpRedirectAddr, if set, specifies the host and port to run the HTTP
+	// to HTTPS redirect server on. For example, ":http" would start a server
+	// on port 80.  If empty, no redirect server is started.
+	HTTPRedirectAddr string `envconfig:"HTTP_REDIRECT_ADDR"`
 }
 
 var defaultOptions = &Options{

docs/reference/readme.md

@@ -31,6 +31,17 @@ Service mode sets the pomerium service(s) to run. If testing, you may want to se
 
 Address specifies the host and port to serve HTTPS and gRPC requests from. If empty, `:https`/`:443` is used.
 
+
+### HTTP Redirect Address
+
+- Environmental Variable: `HTTP_REDIRECT_ADDR`
+- Type: `string`
+- Default: `` (no serevr is started)
+- Example: `:80`
+- Optional
+
+If set, the HTTP Redirect Address specifies the host and port to redirect http to https traffic on. If not set, no redirect server is started. 
+
 ### Shared Secret
 
 - Environmental Variable: `SHARED_SECRET`

internal/urlutil/url.go

@@ -2,6 +2,11 @@ package urlutil // import "github.com/pomerium/pomerium/internal/urlutil"
 
 import "strings"
 
+// StripPort returns a host, without any port number.
+//
+// If Host is an IPv6 literal with a port number, Hostname returns the
+// IPv6 literal without the square brackets. IPv6 literals may include
+// a zone identifier.
 func StripPort(hostport string) string {
 	colon := strings.IndexByte(hostport, ':')
 	if colon == -1 {