외부 의존성 추가: golang.org/x/net/proxy 및 golang.org/x/time/rate 패키지 vendor 디렉토리에 추가

vendor/github.com/gorilla/websocket/proxy.go

@@ -0,0 +1,86 @@
+// Copyright 2017 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"bufio"
+	"encoding/base64"
+	"errors"
+	"log"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"golang.org/x/net/proxy"
+)
+
+type netDialerFunc func(network, addr string) (net.Conn, error)
+
+func (fn netDialerFunc) Dial(network, addr string) (net.Conn, error) {
+	return fn(network, addr)
+}
+
+func init() {
+	proxy.RegisterDialerType("http", func(proxyURL *url.URL, forwardDialer proxy.Dialer) (proxy.Dialer, error) {
+		return &httpProxyDialer{proxyURL: proxyURL, forwardDial: forwardDialer.Dial}, nil
+	})
+}
+
+type httpProxyDialer struct {
+	proxyURL    *url.URL
+	forwardDial func(network, addr string) (net.Conn, error)
+}
+
+func (hpd *httpProxyDialer) Dial(network string, addr string) (net.Conn, error) {
+	hostPort, _ := hostPortNoPort(hpd.proxyURL)
+	conn, err := hpd.forwardDial(network, hostPort)
+	if err != nil {
+		return nil, err
+	}
+
+	connectHeader := make(http.Header)
+	if user := hpd.proxyURL.User; user != nil {
+		proxyUser := user.Username()
+		if proxyPassword, passwordSet := user.Password(); passwordSet {
+			credential := base64.StdEncoding.EncodeToString([]byte(proxyUser + ":" + proxyPassword))
+			connectHeader.Set("Proxy-Authorization", "Basic "+credential)
+		}
+	}
+
+	connectReq := &http.Request{
+		Method: http.MethodConnect,
+		URL:    &url.URL{Opaque: addr},
+		Host:   addr,
+		Header: connectHeader,
+	}
+
+	if err := connectReq.Write(conn); err != nil {
+		if err := conn.Close(); err != nil {
+			log.Printf("httpProxyDialer: failed to close connection: %v", err)
+		}
+		return nil, err
+	}
+
+	// Read response. It's OK to use and discard buffered reader here becaue
+	// the remote server does not speak until spoken to.
+	br := bufio.NewReader(conn)
+	resp, err := http.ReadResponse(br, connectReq)
+	if err != nil {
+		if err := conn.Close(); err != nil {
+			log.Printf("httpProxyDialer: failed to close connection: %v", err)
+		}
+		return nil, err
+	}
+
+	if resp.StatusCode != 200 {
+		if err := conn.Close(); err != nil {
+			log.Printf("httpProxyDialer: failed to close connection: %v", err)
+		}
+		f := strings.SplitN(resp.Status, " ", 2)
+		return nil, errors.New(f[1])
+	}
+	return conn, nil
+}