我正在尝试针对我的 Rails 应用程序在 JavaScript 中创建一个简单的 WebSocket 连接。我得到以下信息:
WebSocket connection to 'ws://localhost:4000/' failed: Error during WebSocket handshake: 'Sec-WebSocket-Accept' header is missing
我做错了什么?这是我的代码:
JavaScript:
var socket = new WebSocket('ws://localhost:4000');
socket.onopen = function() {
var handshake =
"GET / HTTP/1.1\n" +
"Host: localhost\n" +
"Upgrade: websocket\n" +
"Connection: Upgrade\n" +
"Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw==\n" +
"Sec-WebSocket-Protocol: quote\n" +
"Sec-WebSocket-Version: 13\n" +
"Origin: http://localhost\n";
socket.send(handshake);
};
socket.onmessage = function(data) {
console.log(data);
};
ruby :
require 'rubygems'
require 'em-websocket-server'
module QuoteService
class WebSocket < EventMachine::WebSocket::Server
def on_connect
handshake_response = "HTTP/1.1 101 Switching Protocols\n"
handshake_response << "Upgrade: websocket\n"
handshake_response << "Connection: Upgrade\n"
handshake_response << "Sec-WebSocket-Accept: HSmrc0sMlYUkAGmm5OPpG2HaGWk=\n"
handshake_response << "Sec-WebSocket-Protocol: quote\n"
send_message(handshake_response)
end
def on_receive(data)
puts 'RECEIVED: ' + data
end
end
end
EventMachine.run do
print 'Starting WebSocket server...'
EventMachine.start_server '0.0.0.0', 4000, QuoteService::WebSocket
puts 'running'
end
握手 header 符合 Wikipedia .
最佳答案
我认为一旦连接打开,请求和响应就已经发生,所以此时发送 header 为时已晚。此外,标题必须以空白行结尾,而您忽略了这一点。
根据演示,您甚至不必在客户端或服务器中设置 header ——ruby 模块会自动处理服务器端的 header ,而 html5 会自动处理 header 在客户端。我认为这应该有效:
需要“em-websocket-server”
类 EchoServer < EM::WebSocket::Server
def on_connect EM::WebSocket::Log.debug“已连接” 放“我觉得有联系。” 结束
def on_receive 消息 放“收到:#{msg}” 发送消息消息 结束
结束
EM.运行 我的主机=“0.0.0.0” 我的港口= 8000 提出“启动WebSocket服务器。监听端口#{myport} ...” EM.start_server myhost, myport, EchoServer 结束
html文件:
<!DOCTYPE html> <html> <head><title>Test</title>
<script type="text/javascript">
var myWebSocket = new WebSocket("ws://localhost:8000");
myWebSocket.onopen = function(evt) {
console.log("Connection open. Sending message...");
myWebSocket.send("Hello WebSockets!"); };
myWebSocket.onmessage = function(evt) {
console.log(evt.data);
myWebSocket.close(); };
myWebSocket.onclose = function(evt) {
console.log("Connection closed."); };
myWebSocket.onerror = function(err) {
alert(err.name + " => " + err.message); } </script>
</head> <body> <div>Hello</div> </body> </html>
它在 Safari 5.1.9(这是一个较旧的浏览器)中确实有效:我在服务器和客户端上都看到了预期的输出。但是,该代码在 Firefox 21 中不起作用:我收到错误消息...
Firefox can't establish a connection to the server at ws://localhost:8000/.
var myWebSocket = new WebSocket("ws://localhost:8000");
我注意到在 Firebug 和 Safari Developer Tools 中,服务器都没有发送 Sec-WebSocket-Accept header :
Response Headers
Connection Upgrade
Upgrade WebSocket
WebSocket-Location ws://localhost:8000/
WebSocket-Origin null
Request Headers
Accept text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Encoding gzip, deflate
Accept-Language en-US,en;q=0.5
Cache-Control no-cache
Connection keep-alive, Upgrade
DNT 1
Host localhost:8000
Origin null
Pragma no-cache
Sec-WebSocket-Key r9xT+ywe533EHF09wxelkg==
Sec-WebSocket-Version 13
Upgrade websocket
User-Agent Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:21.0) Gecko/20100101 Firefox/21.0
我尝试的任何方法都无法使代码在 Firefox 21.0 中运行。为了检查 Firefox 21.0 是否支持 websockets,我去了:
http://www.websocket.org/echo.html
它说我的浏览器确实支持 websockets。
您有什么理由必须使用 em-websocket-server 模块吗? github 上对该模块的最后修改是三年前。每当您在 ruby 代码中看到
require rubygems
时,就应该提醒您该代码已过时。我尝试了更新的 em-websocket 模块,并且能够在 Firefox 21.0 和 Safari 5.1.9 上使用 websockets 成功地来回传输数据:需要'em-websocket'
我的主机 = "0.0.0.0" 我的端口 = 8000
EM.运行{ 放“监听端口#{myport} ...”
EM::WebSocket.run(:host => myhost, :port => myport, :debug => false) |ws|
ws.onopen do |handshake| path = handshake.path query_str = handshake.query origin = handshake.origin puts "WebSocket opened:" puts "\t path \t\t -> #{path}" puts "\t query_str \t -> #{query_str}" puts "\t origin \t -> #{origin}" end ws.onmessage { |msg| ws.send "Pong: #{msg}" } ws.onclose { puts "WebSocket closed" } ws.onerror { |e| puts "Error: #{e.message}" }
结束
相同的客户端代码。现在响应 header 包括 Sec-WebSocket-Accept:
Response Headers
Connection Upgrade
Sec-WebSocket-Accept LyIm6d+kAAqkcTR744tVK9HMepY=
Upgrade websocket
Request Headers
Accept text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Encoding gzip, deflate
Accept-Language en-US,en;q=0.5
Cache-Control no-cache
Connection keep-alive, Upgrade
DNT 1
Host localhost:8000
Origin null
Pragma no-cache
Sec-WebSocket-Key pbK8lFHQAF+arl9tFvHn/Q==
Sec-WebSocket-Version 13
Upgrade websocket
User-Agent Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:21.0) Gecko/20100101 Firefox/21.0
在您的代码中,我认为您没有设置任何 header 。相反,您只是来回发送恰好包含看起来像标题的字符的消息。显然,您的浏览器在允许连接之前需要响应中的 Sec-WebSocket-Accept header ,并且当 em-websocket-server 模块无法在响应中设置该 header 时,您的浏览器将拒绝连接。
em-websockets-server 的相关源代码如下所示:
module EM
module WebSocket
module Protocol
module Version76
# generate protocol 76 compatible response headers
def response
response = "HTTP/1.1 101 Web Socket Protocol Handshake\r\n"
response << "Upgrade: WebSocket\r\n"
response << "Connection: Upgrade\r\n"
response << "Sec-WebSocket-Origin: #{origin}\r\n"
response << "Sec-WebSocket-Location: #{scheme}://#{host}#{path}\r\n"
if protocol
response << "Sec-WebSocket-Protocol: #{protocol}\r\n"
end
response << "\r\n"
response << Digest::MD5.digest(keyset)
response
end
如您所见,它没有设置 Sec-WebSocket-Accept header 。该代码位于一个名为 Version76 的模块中,在 google 上搜索 websockets version 76 会得到一个过时的协议(protocol)(其中包含一个请求和响应的示例):
https://datatracker.ietf.org/doc/html/draft-hixie-thewebsocketprotocol-76
这是当前的 websockets 协议(protocol)(其中还包含请求和响应的示例):
https://www.rfc-editor.org/rfc/rfc6455
结论:em-websockets-server 已过时。
关于javascript - 使用 Ruby 和 EM::WebSocket::Server 的 WebSocket 握手,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/17374453/