websocketproxy

README

WebsocketProxy

WebsocketProxy is an http.Handler interface build on top of gorilla/websocket that you can plug into your existing Go webserver to provide WebSocket reverse proxy.

Install

go get github.com/koding/websocketproxy

Example

Below is a simple server that proxies to the given backend URL

package main

import (
	"flag"
	"net/http"
	"net/url"

	"github.com/koding/websocketproxy"
)

var (
	flagBackend = flag.String("backend", "", "Backend URL for proxying")
)

func main() {
	u, err := url.Parse(*flagBackend)
	if err != nil {
		log.Fatalln(err)
	}

	err = http.ListenAndServe(":80", websocketproxy.NewProxy(u))
	if err != nil {
		log.Fatalln(err)
	}
}

Save it as proxy.go and run as:

go run proxy.go -backend ws://example.com:3000

Now all incoming WebSocket requests coming to this server will be proxied to ws://example.com:3000

Documentation

Overview

Package websocketproxy is a reverse proxy for WebSocket connections.

Index

• Variables
• func ProxyHandler(target *url.URL) http.Handler
• type MessageReplicatorFunc
• type WebsocketProxy
  • func NewProxy(target *url.URL) *WebsocketProxy
  • func (w *WebsocketProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request)

Variables

var (
	// DefaultUpgrader specifies the parameters for upgrading an HTTP
	// connection to a WebSocket connection.
	DefaultUpgrader = &websocket.Upgrader{
		ReadBufferSize:  1024,
		WriteBufferSize: 1024,
	}

	// DefaultDialer is a dialer with all fields set to the default zero values.
	DefaultDialer = websocket.DefaultDialer

	// DefaultReplicator is a simple message passthrough
	DefaultReplicator = passthroughReplicator
)

Functions

func ProxyHandler

func ProxyHandler(target *url.URL) http.Handler

ProxyHandler returns a new http.Handler interface that reverse proxies the request to the given target.

Types

type MessageReplicatorFunc

type MessageReplicatorFunc func(dst, src *websocket.Conn, errc chan error)

type WebsocketProxy

type WebsocketProxy struct {
	// Director, if non-nil, is a function that may copy additional request
	// headers from the incoming WebSocket connection into the output headers
	// which will be forwarded to another server.
	Director func(incoming *http.Request, out http.Header)

	// IncomeReplicator is a function that forward messages incoming from origin
	// into the backend. If nil, passthroughsReplicator is used.
	IncomeReplicator MessageReplicatorFunc

	// BackendReplicator is a function that forwards messages from backend into
	// origin. If nil, passthroughsReplicator is used.
	BackendReplicator MessageReplicatorFunc

	// Backend returns the backend URL which the proxy uses to reverse proxy
	// the incoming WebSocket connection. Request is the initial incoming and
	// unmodified request.
	Backend func(*http.Request) *url.URL

	// Upgrader specifies the parameters for upgrading a incoming HTTP
	// connection to a WebSocket connection. If nil, DefaultUpgrader is used.
	Upgrader *websocket.Upgrader

	//  Dialer contains options for connecting to the backend WebSocket server.
	//  If nil, DefaultDialer is used.
	Dialer *websocket.Dialer
}

WebsocketProxy is an HTTP Handler that takes an incoming WebSocket connection and proxies it to another server.

func NewProxy

func NewProxy(target *url.URL) *WebsocketProxy

NewProxy returns a new Websocket reverse proxy that rewrites the URL's to the scheme, host and base path provider in target.

func (*WebsocketProxy) ServeHTTP

func (w *WebsocketProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request)

ServeHTTP implements the http.Handler that proxies WebSocket connections.