编辑:最后显示,发现实际创建了升级标头。
我在action-cable-example代码库中工作,尝试构建一个WebSocket应用程序。 " Chatty"应用程序,取决于应用程序中提供的浏览器客户端,工作正常。但是,我不打算使用该客户端,因为我需要外部IoT连接。因此,我正在尝试将ws / wss WebSocket协议实现到外部非浏览器设备,并且我在route.rb中的连接是:
mount ActionCable.server => '/cable'
我使用sample / client.rb尝试过多个外部客户端,例如Chrome Simple WebSocket Client扩展和gem websocket-client-simple。在这两种情况下,ActionCable都不返回升级头。 Chrome扩展程序抱怨如下:
WebSocket connection to 'ws://127.0.0.1:3000/cable' failed: Error during WebSocket handshake: 'Upgrade' header is missing
实际握手显示为真,如:
**General**
Request URL:ws://127.0.0.1:3000/cable
Request Method:GET
Status Code:101 Switching Protocols
**Response Headers**
view source
Connection:keep-alive
Server:thin
**Request Headers**
view source
Accept-Encoding:gzip, deflate, sdch
Accept-Language:en-US,en;q=0.8
Cache-Control:no-cache
Connection:Upgrade
Cookie:PPA_ID=<redacted>
DNT:1
Host:127.0.0.1:3000
Origin:chrome-extension://pfdhoblngboilpfeibdedpjgfnlcodoo
Pragma:no-cache
Sec-WebSocket-Extensions:permessage-deflate; client_max_window_bits
Sec-WebSocket-Key:1vokmzewcWf9e2RwMth0Lw==
Sec-WebSocket-Version:13
Upgrade:websocket
User-Agent:Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.84 Safari/537.36
根据标准,响应头应为:
HTTP/1.1 101 Switching Protocols
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Accept: HSmrc0sMlYUkAGmm5OPpG2HaGWk=
Sec-WebSocket-Protocol: chat
Sec-WebSocket-Accept特别重要,因为它基于请求头的Sec-WebSocket-Key进行计算,以确认ws / wss被理解并且切换协议应该发生。
在所有这些过程中,服务器更加满意,直到客户端被勾选并关闭连接:
Started GET "/cable" for 127.0.0.1 at 2016-06-16 19:19:17 -0400
ActiveRecord::SchemaMigration Load (1.0ms) SELECT "schema_migrations".* FROM "schema_migrations"
Started GET "/cable/" [WebSocket] for 127.0.0.1 at 2016-06-16 19:19:17 -0400
Successfully upgraded to WebSocket (REQUEST_METHOD: GET, HTTP_CONNECTION: Upgrade, HTTP_UPGRADE: websocket)
Finished "/cable/" [WebSocket] for 127.0.0.1 at 2016-06-16 19:19:18 -0400
看看websocket-client-simple,我把WebSocket分解回client.rb,它也显示了空标题。我正在显示代码,然后是WebSocket:
url = ARGV.shift || 'ws://localhost:3000/cable'
ws = WebSocket::Client::Simple.connect url
#<WebSocket::Client::Simple::Client:0x2cdaf68
@url="ws://localhost:3000/cable",
@socket=#<TCPSocket:fd 3>,
@handshake=<WebSocket::Handshake::Client:0x013231c8
@url="ws://localhost:3000/cable",
@headers={},
@state=:new,
@handler=#<WebSocket::Handshake::Handler::Client11:0x2e88400
@handshake=<WebSocket::Handshake::Client:0x013231c8
@url="ws://localhost:3000/cable",
@headers={},
@state=:new,
@handler=#<WebSocket::Handshake::Handler::Client11:0x2e88400 ...>,
@data="",
@secure=false,
@host="localhost",
@port=3000,
@path="/cable",
@query=nil,
@version=13>,
@key="KUJ0/C0rvoCMruW8STp0Sw==">,
@data="",
@secure=false,
@host="localhost",
@port=3000,
@path="/cable",
@query=nil,
@version=13>,
@handshaked=false,
@pipe_broken=false,
@closed=false,
@__events=[{:type=>:__close, :listener=>#<Proc:0x2d10ae8@D:/Bitnami/rubystack-2.2.5-3/projects/websocket-client-simple/lib/websocket-client-simple/client.rb:37>, :params=>{:once=>true}, :id=>0}],
@thread=#<Thread:0x2d10a70@D:/Bitnami/rubystack-2.2.5-3/projects/websocket-client-simple/lib/websocket-client-simple/client.rb:42 sleep>
>;
在这个回复中,我注意到实例变量&#34; @ handshaked&#34;返回为false。这可能是相关的,但到目前为止我还没有找到代码中设置或引用的位置。
更新: 发现WebSocket :: Driver.start实际上创建了升级头。并且,@ socket.write(响应)应通过EventMachine发送出去。 代码:
def start
return false unless @ready_state == 0
response = handshake_response
return false unless response
@socket.write(response)
open unless @stage == -1
true
end
handshake_response是:
HTTP/1.1 101 Switching Protocols
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Accept: iJVnsG1ApNMFzABXGDSHN1V0i/s=
答案 0 :(得分:7)
问题是我正在尝试在开发中使用Thin服务器。它会运作。但是,它实际上是在处理过程中传输响应头,例如:
Response Headers
Connection:keep-alive
Server:thin
ActionCable实际上是在发送相应的升级标头,但只有在Thin发出自己的标头后才会这样做,因此客户端无法识别它们。
转换回Puma后,我按预期收到了这些:
Response Headers
HTTP/1.1 101 Switching Protocols
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Accept: XJOmp1e2IwQIMk5n0JV/RZZSIhs=