CGI support

config.go

@@ -41,6 +41,7 @@ func parseCommandLine() Config {
 	reverseLookupFlag := flag.Bool("reverselookup", true, "Perform reverse DNS lookups on remote clients")
 	scriptDirFlag := flag.String("dir", "", "Base directory for WebSocket scripts")
 	staticDirFlag := flag.String("staticdir", "", "Serve static content from this directory over HTTP")
+	cgiDirFlag := flag.String("cgidir", "", "Serve CGI scripts from this directory over HTTP")
 	devConsoleFlag := flag.Bool("devconsole", false, "Enable development console (cannot be used in conjuction with --staticdir)")
 
 	flag.Parse()
@@ -75,6 +76,7 @@ func parseCommandLine() Config {
 	config.ReverseLookup = *reverseLookupFlag
 	config.ScriptDir = *scriptDirFlag
 	config.StaticDir = *staticDirFlag
+	config.CgiDir = *cgiDirFlag
 	config.DevConsole = *devConsoleFlag
 	config.StartupTime = time.Now()
 	config.ServerSoftware = fmt.Sprintf("websocketd/%s", Version())
@@ -96,8 +98,8 @@ func parseCommandLine() Config {
 	}
 
 	args := flag.Args()
-	if len(args) < 1 && config.ScriptDir == "" {
-		fmt.Fprintf(os.Stderr, "Please specify COMMAND or provide --dir argument.\n")
+	if len(args) < 1 && config.ScriptDir == "" && config.StaticDir == "" && config.CgiDir == "" {
+		fmt.Fprintf(os.Stderr, "Please specify COMMAND or provide --dir, --staticdir or --cgidir argument.\n")
 		os.Exit(1)
 	}
 

examples/cgi-bin/README.txt

@@ -0,0 +1,8 @@
+This examples directory shows how websocketd can also serve CGI scripts via HTTP.
+
+$ websocketd --port=1234 --cgidir=examples/cgi-bin
+# Then access http://localhost:1234/dump-env.sh
+
+
+You can also test the command files by running from the command line.
+

examples/cgi-bin/dump-env.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+
+# Copyright 2013 Joe Walnes and the websocketd team.
+# All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# Standard CGI(ish) environment variables, as defined in
+# http://tools.ietf.org/html/rfc3875
+NAMES="""
+  AUTH_TYPE
+  CONTENT_LENGTH
+  CONTENT_TYPE
+  GATEWAY_INTERFACE
+  PATH_INFO
+  PATH_TRANSLATED
+  QUERY_STRING
+  REMOTE_ADDR
+  REMOTE_HOST
+  REMOTE_IDENT
+  REMOTE_PORT
+  REMOTE_USER
+  REQUEST_METHOD
+  REQUEST_URI
+  SCRIPT_NAME
+  SERVER_NAME
+  SERVER_PORT
+  SERVER_PROTOCOL
+  SERVER_SOFTWARE
+  UNIQUE_ID
+"""
+
+echo "Content-type: text/plain"
+echo
+
+for NAME in ${NAMES}
+do
+	echo ${NAME}=${!NAME:-<unset>}
+done
+
+# Additional HTTP headers
+env | grep '^HTTP_'

help.go

@@ -49,11 +49,8 @@ Options:
                                  options should not be specified.
 
   --staticdir=DIR                Serve static files in this directory over HTTP.
-                                 If a static file has the same filename as a
-                                 WebSocket handler, the WebSocket handler will
-                                 always take priority.
-                                 This flag cannot be used in conjunction
-                                 with --devconsole.
+
+  --cgidir=DIR                   Serve CGI scripts in this directory over HTTP.
 
   --help                         Print help and exit.
 
@@ -69,7 +66,7 @@ Options:
                                  endpoint at ws://[host]/foo, you can
                                  visit http://[host]/foo in your browser.
                                  This flag cannot be used in conjunction
-                                 with --staticdir.
+                                 with --staticdir or --cgidir.
 
   --loglevel={debug,             Log level to use (from most to least
               trace,             verbose).

libwebsocketd/config.go

@@ -17,7 +17,8 @@ type Config struct {
 	UsingScriptDir bool      // Are we running with a script dir.
 	StartupTime    time.Time // Server startup time (used for dev console caching).
 	StaticDir      string    // If set, static files will be served from this dir over HTTP.
-	DevConsole     bool      // Enable dev console. This disables StaticDir.
+	CgiDir         string    // If set, CGI scripts will be served from this dir over HTTP.
+	DevConsole     bool      // Enable dev console. This disables StaticDir and CgiDir.
 	ServerSoftware string    // Value to pass to SERVER_SOFTWARE environment variable (e.g. websocketd/1.2.3).
 	Env            []string  // Additional environment variables to pass to process ("key=value").
 }

libwebsocketd/env.go

@@ -8,6 +8,7 @@ package libwebsocketd
 import (
 	"fmt"
 	"net"
+	"net/http"
 	"os"
 	"strconv"
 	"strings"
@@ -27,8 +28,8 @@ func generateId() string {
 	return strconv.FormatInt(time.Now().UnixNano(), 10)
 }
 
-func remoteDetails(ws *websocket.Conn, config *Config) (string, string, string, error) {
-	remoteAddr, remotePort, err := net.SplitHostPort(ws.Request().RemoteAddr)
+func remoteDetails(req *http.Request, config *Config) (string, string, string, error) {
+	remoteAddr, remotePort, err := net.SplitHostPort(req.RemoteAddr)
 	if err != nil {
 		return "", "", "", err
 	}
@@ -53,7 +54,7 @@ func createEnv(ws *websocket.Conn, config *Config, urlInfo *URLInfo, id string)
 	headers := req.Header
 	url := req.URL
 
-	remoteAddr, remoteHost, remotePort, err := remoteDetails(ws, config)
+	remoteAddr, remoteHost, remotePort, err := remoteDetails(ws.Request(), config)
 	if err != nil {
 		return nil, err
 	}

libwebsocketd/http.go

@@ -6,12 +6,15 @@
 package libwebsocketd
 
 import (
+	"code.google.com/p/go.net/websocket"
 	"fmt"
 	"net/http"
+	"net/http/cgi"
+	"os"
+	"path"
+	"path/filepath"
 	"strconv"
 	"strings"
-
-	"code.google.com/p/go.net/websocket"
 )
 
 type HttpWsMuxHandler struct {
@@ -22,8 +25,20 @@ type HttpWsMuxHandler struct {
 // Main HTTP handler. Muxes between WebSocket handler, DevConsole or 404.
 func (h HttpWsMuxHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 	hdrs := req.Header
+
+	log := h.Log.NewLevel(h.Log.LogFunc)
+	log.Associate("url", fmt.Sprintf("http://%s%s", req.RemoteAddr, req.URL.RequestURI()))
+
+	_, remoteHost, _, err := remoteDetails(req, h.Config)
+	if err != nil {
+		log.Error("session", "Could not understand remote address '%s': %s", req.RemoteAddr, err)
+		return
+	}
+
+	log.Associate("remote", remoteHost)
+
+	// WebSocket
 	if strings.ToLower(hdrs.Get("Upgrade")) == "websocket" && strings.ToLower(hdrs.Get("Connection")) == "upgrade" {
-		// WebSocket
 
 		if hdrs.Get("Origin") == "null" {
 			// Fix up mismatch between how Chrome reports Origin
@@ -32,40 +47,58 @@ func (h HttpWsMuxHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 			hdrs.Set("Origin", "file:")
 		}
 
-		wsHandler := websocket.Handler(func(ws *websocket.Conn) {
-			acceptWebSocket(ws, h.Config, h.Log)
-		})
-		wsHandler.ServeHTTP(w, req)
-	} else if h.Config.DevConsole {
-		// Dev console (if enabled)
+		if h.Config.CommandName != "" || h.Config.UsingScriptDir {
+			wsHandler := websocket.Handler(func(ws *websocket.Conn) {
+				acceptWebSocket(ws, h.Config, log)
+			})
+			wsHandler.ServeHTTP(w, req)
+			return
+		}
+	}
+
+	// Dev console (if enabled)
+	if h.Config.DevConsole {
 		content := strings.Replace(ConsoleContent, "{{license}}", License, -1)
 		http.ServeContent(w, req, ".html", h.Config.StartupTime, strings.NewReader(content))
-	} else if h.Config.StaticDir != "" {
-		// Serve static files
+		return
+	}
+
+	// CGI scripts
+	if h.Config.CgiDir != "" {
+		filePath := path.Join(h.Config.CgiDir, fmt.Sprintf(".%s", filepath.FromSlash(req.URL.Path)))
+
+		if fi, err := os.Stat(filePath); err == nil && !fi.IsDir() {
+			cgiHandler := &cgi.Handler{
+				Path: filePath,
+			}
+			log.Associate("cgiscript", filePath)
+			log.Access("http", "CGI")
+			cgiHandler.ServeHTTP(w, req)
+			return
+		}
+	}
+
+	// Static files
+	if h.Config.StaticDir != "" {
 		handler := http.FileServer(http.Dir(h.Config.StaticDir))
+		log.Access("http", "STATIC")
 		handler.ServeHTTP(w, req)
-	} else {
-		// 404
-		http.NotFound(w, req)
+		return
 	}
+
+	// 404
+	log.Access("http", "NOT FOUND")
+	http.NotFound(w, req)
 }
 
 func acceptWebSocket(ws *websocket.Conn, config *Config, log *LogScope) {
 	defer ws.Close()
 
 	req := ws.Request()
 	id := generateId()
-	_, remoteHost, _, err := remoteDetails(ws, config)
-	if err != nil {
-		log.Error("session", "Could not understand remote address '%s': %s", req.RemoteAddr, err)
-		return
-	}
 
-	log = log.NewLevel(log.LogFunc)
 	log.Associate("id", id)
-	log.Associate("url", fmt.Sprintf("http://%s%s", req.RemoteAddr, req.URL.RequestURI()))
 	log.Associate("origin", req.Header.Get("Origin"))
-	log.Associate("remote", remoteHost)
 
 	log.Access("session", "CONNECT")
 	defer log.Access("session", "DISCONNECT")

main.go

@@ -40,27 +40,36 @@ func main() {
 
 	log := libwebsocketd.RootLogScope(config.LogLevel, log)
 
-	if config.DevConsole && config.StaticDir != "" {
-		log.Fatal("server", "Invalid parameters: --devconsole cannot be used with --staticdir. Pick one.")
-		os.Exit(4)
+	if config.DevConsole {
+		if config.StaticDir != "" {
+			log.Fatal("server", "Invalid parameters: --devconsole cannot be used with --staticdir. Pick one.")
+			os.Exit(4)
+		}
+		if config.CgiDir != "" {
+			log.Fatal("server", "Invalid parameters: --devconsole cannot be used with --cgidir. Pick one.")
+			os.Exit(4)
+		}
 	}
 
 	http.Handle(config.BasePath, libwebsocketd.HttpWsMuxHandler{
 		Config: config.Config,
 		Log:    log})
 
-	log.Info("server", "Starting WebSocket server : ws://%s%s", config.Addr, config.BasePath)
+	log.Info("server", "Starting WebSocket server   : ws://%s%s", config.Addr, config.BasePath)
 	if config.DevConsole {
-		log.Info("server", "Developer console enabled : http://%s/", config.Addr)
+		log.Info("server", "Developer console enable  d : http://%s/", config.Addr)
 	}
 	if config.UsingScriptDir {
-		log.Info("server", "Serving from directory    : %s", config.ScriptDir)
-	} else {
-		log.Info("server", "Serving using application : %s %s", config.CommandName, strings.Join(config.CommandArgs, " "))
+		log.Info("server", "Serving from directory      : %s", config.ScriptDir)
+	} else if config.CommandName != "" {
+		log.Info("server", "Serving using application   : %s %s", config.CommandName, strings.Join(config.CommandArgs, " "))
 	}
 	if config.StaticDir != "" {
 		log.Info("server", "Serving static content from : %s", config.StaticDir)
 	}
+	if config.CgiDir != "" {
+		log.Info("server", "Serving CGI scripts from    : %s", config.CgiDir)
+	}
 
 	err := http.ListenAndServe(config.Addr, nil)
 	if err != nil {