Filled out more web socket stuff

middleware/websockets/websocket.go

 package websockets
 
 import (
+	"net"
+	"net/http"
 	"os/exec"
+	"strings"
 
 	"golang.org/x/net/websocket"
 )
 
-// WebSocket represents a web socket server configuration.
+// WebSocket represents a web socket server instance. A WebSocket
+// struct is instantiated for each new websocket request.
 type WebSocket struct {
-	Path      string
-	Command   string
-	Arguments []string
+	WSConfig
+	*http.Request
 }
 
 // Handle handles a WebSocket connection. It launches the
@@ -21,12 +24,67 @@ func (ws WebSocket) Handle(conn *websocket.Conn) {
 	cmd.Stdin = conn
 	cmd.Stdout = conn
 
-	// TODO: Set environment variables according to CGI 1.1
-	// cf. http://tools.ietf.org/html/rfc3875#section-4.1.4
-	cmd.Env = append(cmd.Env, `GATEWAY_INTERFACE="caddy-CGI/1.1"`)
+	err := ws.buildEnv(cmd)
+	if err != nil {
+		// TODO
+	}
 
-	err := cmd.Run()
+	err = cmd.Run()
 	if err != nil {
 		panic(err)
 	}
 }
+
+// buildEnv sets the meta-variables for the child process according
+// to the CGI 1.1 specification: http://tools.ietf.org/html/rfc3875#section-4.1
+func (ws WebSocket) buildEnv(cmd *exec.Cmd) error {
+	remoteHost, remotePort, err := net.SplitHostPort(ws.RemoteAddr)
+	if err != nil {
+		return err
+	}
+	serverHost, serverPort, err := net.SplitHostPort(ws.Host)
+	if err != nil {
+		return err
+	}
+
+	cmd.Env = []string{
+		`AUTH_TYPE=`,      // Not used
+		`CONTENT_LENGTH=`, // Not used
+		`CONTENT_TYPE=`,   // Not used
+		`GATEWAY_INTERFACE=` + gatewayInterface,
+		`PATH_INFO=`,       // TODO
+		`PATH_TRANSLATED=`, // TODO
+		`QUERY_STRING=` + ws.URL.RawQuery,
+		`REMOTE_ADDR=` + remoteHost,
+		`REMOTE_HOST=` + remoteHost, // TODO (Host lookups are slow; make this configurable)
+		`REMOTE_IDENT=`,             // Not used
+		`REMOTE_PORT=` + remotePort,
+		`REMOTE_USER=`, // Not used,
+		`REQUEST_METHOD=` + ws.Method,
+		`REQUEST_URI=` + ws.RequestURI,
+		`SCRIPT_NAME=`, // TODO - absolute path to program being executed?
+		`SERVER_NAME=` + serverHost,
+		`SERVER_PORT=` + serverPort,
+		`SERVER_PROTOCOL=` + ws.Proto,
+		`SERVER_SOFTWARE=` + serverSoftware,
+	}
+
+	// Add each HTTP header to the environment as well
+	for header, values := range ws.Header {
+		value := strings.Join(values, ", ")
+		header = strings.ToUpper(header)
+		header = strings.Replace(header, "-", "_", -1)
+		value = strings.Replace(value, "\n", " ", -1)
+		cmd.Env = append(cmd.Env, "HTTP_"+header+"="+value)
+	}
+
+	return nil
+}
+
+const (
+	// See CGI spec, 4.1.4
+	gatewayInterface = "caddy-CGI/1.1"
+
+	// See CGI spec, 4.1.17
+	serverSoftware = "caddy/0.1.0"
+)

middleware/websockets/websockets.go

@@ -4,7 +4,7 @@
 package websockets
 
 import (
-	"log"
+	"errors"
 	"net/http"
 
 	"github.com/flynn/go-shlex"
@@ -12,16 +12,31 @@ import (
 	"golang.org/x/net/websocket"
 )
 
-// WebSockets is a type which holds configuration
-// for the websocket middleware collectively.
-type WebSockets struct {
-	Sockets []WebSocket
-}
+type (
+	// WebSockets is a type that holds configuration for the
+	// websocket middleware generally, like a list of all the
+	// websocket endpoints.
+	WebSockets struct {
+		Sockets []WSConfig
+	}
+
+	// WSConfig holds the configuration for a single websocket
+	// endpoint which may serve zero or more websocket connections.
+	WSConfig struct {
+		Path      string
+		Command   string
+		Arguments []string
+	}
+)
 
-// ServeHTTP more or less converts the HTTP request to a WebSocket connection.
+// ServeHTTP converts the HTTP request to a WebSocket connection and serves it up.
 func (ws WebSockets) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-	for _, socket := range ws.Sockets {
-		if middleware.Path(r.URL.Path).Matches(socket.Path) {
+	for _, sockconfig := range ws.Sockets {
+		if middleware.Path(r.URL.Path).Matches(sockconfig.Path) {
+			socket := WebSocket{
+				WSConfig: sockconfig,
+				Request:  r,
+			}
 			websocket.Handler(socket.Handle).ServeHTTP(w, r)
 			return
 		}
@@ -30,7 +45,7 @@ func (ws WebSockets) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 // New constructs and configures a new websockets middleware instance.
 func New(c middleware.Controller) (middleware.Middleware, error) {
-	var websocks []WebSocket
+	var websocks []WSConfig
 
 	var path string
 	var command string
@@ -62,9 +77,9 @@ func New(c middleware.Controller) (middleware.Middleware, error) {
 
 		parts, err := shlex.Split(command)
 		if err != nil {
-			log.Fatal("Error parsing command for websocket use: " + err.Error())
+			return nil, errors.New("Error parsing command for websocket use: " + err.Error())
 		} else if len(parts) == 0 {
-			log.Fatal("No command found for use by websocket.")
+			return nil, errors.New("No command found for use by websocket")
 		}
 
 		cmd = parts[0]
@@ -72,7 +87,7 @@ func New(c middleware.Controller) (middleware.Middleware, error) {
 			args = parts[1:]
 		}
 
-		websocks = append(websocks, WebSocket{
+		websocks = append(websocks, WSConfig{
 			Path:      path,
 			Command:   cmd,
 			Arguments: args,