Merge pull request joewalnes#208 from asergeyev/i206

Feature that allows to open secondary HTTP port...

config.go

@@ -22,6 +22,7 @@ type Config struct {
 	Addr              []string // TCP addresses to listen on. e.g. ":1234", "1.2.3.4:1234" or "[::1]:1234"
 	MaxForks          int      // Number of allowable concurrent forks
 	LogLevel          libwebsocketd.LogLevel
+	RedirPort         int
 	CertFile, KeyFile string
 	*libwebsocketd.Config
 }
@@ -71,6 +72,7 @@ func parseCommandLine() *Config {
 	sslCert := flag.String("sslcert", "", "Should point to certificate PEM file when --ssl is used")
 	sslKey := flag.String("sslkey", "", "Should point to certificate private key file when --ssl is used")
 	maxForksFlag := flag.Int("maxforks", 0, "Max forks, zero means unlimited")
+	redirPortFlag := flag.Int("redirport", 0, "HTTP port to redirect to canonical --port address")
 
 	// lib config options
 	binaryFlag := flag.Bool("binary", false, "Set websocketd to experimental binary mode (default is line by line)")
@@ -119,6 +121,7 @@ func parseCommandLine() *Config {
 		mainConfig.Addr = []string{fmt.Sprintf(":%d", port)}
 	}
 	mainConfig.MaxForks = *maxForksFlag
+	mainConfig.RedirPort = *redirPortFlag
 	mainConfig.LogLevel = libwebsocketd.LevelFromString(*logLevelFlag)
 	if mainConfig.LogLevel == libwebsocketd.LogUnknown {
 		fmt.Printf("Incorrect loglevel flag '%s'. Use --help to see allowed values.\n", *logLevelFlag)

help.go

@@ -51,6 +51,11 @@ Options:
   --sslcert=FILE                 All three options must be used or all of
   --sslkey=FILE                  them should be omitted. 
 
+  --redirport=PORT               Open alternative port and redirect HTTP traffic
+                                 from it to canonical address (mostly useful
+                                 for HTTPS-only configurations to redirect HTTP
+                                 traffic)
+
   --passenv VAR[,VAR...]         Lists environment variables allowed to be
                                  passed to executed scripts.
 

main.go

@@ -9,6 +9,7 @@ import (
 	"fmt"
 	"net/http"
 	"os"
+	"strconv"
 	"strings"
 
 	"github.com/joewalnes/websocketd/libwebsocketd"
@@ -76,13 +77,34 @@ func main() {
 		// ListenAndServe is blocking function. Let's run it in
 		// go routine, reporting result to control channel.
 		// Since it's blocking it'll never return non-error.
+
 		go func(addr string) {
 			if config.Ssl {
 				rejects <- http.ListenAndServeTLS(addr, config.CertFile, config.KeyFile, nil)
 			} else {
 				rejects <- http.ListenAndServe(addr, nil)
 			}
 		}(addrSingle)
+
+		if config.RedirPort != 0 {
+			go func(addr string) {
+				pos := strings.IndexByte(addr, ':')
+				rediraddr := addr[:pos] + ":" + strconv.Itoa(config.RedirPort) // it would be silly to optimize this one
+				redir := &http.Server{Addr: rediraddr, Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+
+					// redirect to same hostname as in request but different port and probably schema
+					uri := "https://"
+					if !config.Ssl {
+						uri = "http://"
+					}
+					uri += r.Host[:strings.IndexByte(r.Host, ':')] + addr[pos:] + "/"
+
+					http.Redirect(w, r, uri, http.StatusMovedPermanently)
+				})}
+				log.Info("server", "Starting redirect server   : http://%s/", rediraddr)
+				rejects <- redir.ListenAndServe()
+			}(addrSingle)
+		}
 	}
 	select {
 	case err := <-rejects: