feat:(conn): add RemoteAddr and LocalAddr method

accept.go

@@ -11,10 +11,12 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"net"
 	"net/http"
 	"net/textproto"
 	"net/url"
 	"path"
+	"strconv"
 	"strings"
 
 	"github.com/coder/websocket/internal/errd"
@@ -150,12 +152,34 @@ func accept(w http.ResponseWriter, r *http.Request, opts *AcceptOptions) (_ *Con
 	b, _ := brw.Reader.Peek(brw.Reader.Buffered())
 	brw.Reader.Reset(io.MultiReader(bytes.NewReader(b), netConn))
 
+	ipStr, portStr, err := net.SplitHostPort(r.RemoteAddr)
+	if err != nil {
+		err = errors.New("*http.Request contains invalid RemoteAddr")
+		http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
+		return nil, err
+	}
+
+	ip := net.ParseIP(ipStr)
+	if ip == nil {
+		err = errors.New("*http.Request contains invalid IP address")
+		http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
+		return nil, err
+	}
+
+	port, err := strconv.Atoi(portStr)
+	if err != nil {
+		err = errors.New("*http.Request contains invalid port number")
+		http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
+		return nil, err
+	}
+
 	return newConn(connConfig{
 		subprotocol:    w.Header().Get("Sec-WebSocket-Protocol"),
 		rwc:            netConn,
 		client:         false,
 		copts:          copts,
 		flateThreshold: opts.CompressionThreshold,
+		remoteAddr:     &net.TCPAddr{IP: ip, Port: port},
 
 		br: brw.Reader,
 		bw: brw.Writer,

conn.go

@@ -49,6 +49,7 @@ type Conn struct {
 	client         bool
 	copts          *compressionOptions
 	flateThreshold int
+	remoteAddr     net.Addr
 	br             *bufio.Reader
 	bw             *bufio.Writer
 
@@ -88,6 +89,7 @@ type connConfig struct {
 	client         bool
 	copts          *compressionOptions
 	flateThreshold int
+	remoteAddr     net.Addr
 
 	br *bufio.Reader
 	bw *bufio.Writer
@@ -100,6 +102,7 @@ func newConn(cfg connConfig) *Conn {
 		client:         cfg.client,
 		copts:          cfg.copts,
 		flateThreshold: cfg.flateThreshold,
+		remoteAddr:     cfg.remoteAddr,
 
 		br: cfg.br,
 		bw: cfg.bw,
@@ -192,6 +195,11 @@ func (c *Conn) flate() bool {
 	return c.copts != nil
 }
 
+// RemoteAddr returns the remote address of websocket connection.
+func (c *Conn) RemoteAddr() net.Addr {
+	return c.remoteAddr
+}
+
 // Ping sends a ping to the peer and waits for a pong.
 // Use this to measure latency or ensure the peer is responsive.
 // Ping must be called concurrently with Reader as it does

internal/examples/echo/server.go

@@ -30,6 +30,8 @@ func (s echoServer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	defer c.CloseNow()
 
+	s.logf("new incoming connection: %s", c.RemoteAddr().String())
+
 	if c.Subprotocol() != "echo" {
 		c.Close(websocket.StatusPolicyViolation, "client must speak the echo subprotocol")
 		return