ios - Swift Network.framework WebSocket 握手 nil 返回

Question

我正在尝试使用新的 Network.framework 连接到 WebSocket，但面临来自服务器的零握手响应。

(是的，我知道红蜘蛛存在，但它不支持代理/移动用户在网络接口(interface)之间切换)

我的测试代码:

func beginTest() {

    let connection = NWConnection(host: "echo.websocket.org", port: 443, using: .tls)

    connection.stateUpdateHandler = { state in
        print("State:", state)
        switch state {
        case .ready:
            self.connectionReady(connection)
        default:
            break
        }
    }
    connection.start(queue: .main)
}

func connectionReady(_ connection: NWConnection) {

    let raw = """
    GET / HTTP/1.1
    Upgrade: websocket
    Connection: Upgrade
    Host: echo.websocket.org
    Origin: https://echo.websocket.org
    Sec-WebSocket-Key: s04nPqA7M6pQ3Lu2jRJLSQ==
    Sec-WebSocket-Version: 13
    """

    let rawData = raw.appending("\n\n\n").replacingOccurrences(of: "\n", with: "\r\n").data(using: .utf8)

    connection.send(content: rawData!, completion: .idempotent)

    connection.receiveMessage(completion: {data, context, bool, error in
        if let data = data {
            print("Received:", String(data: data, encoding: .utf8))
        }

        print("Error:", error)

        let hello = "Hello".data(using: .utf8)
        connection.send(content: hello, completion: .idempotent)
    })
}

这是零响应和连接断开，而不是从服务器获取升级握手响应，下面带有控制台日志:

State: preparing
State: ready
Received: nil
Error: nil
2018-10-08 11:38:57.314885+0800 SwiftNetworkTest[86448:3026660] [] nw_socket_handle_socket_event [C1.1:2] Socket SO_ERROR [54: Connection reset by peer]

谁能指导我如何使用 Apple 新的 Network.framework？将不胜感激!

更新1

我的错，我现在可以使用 .ascii 看到握手响应编码而不是 .utf8 .

但我的连接仍然断开 Connection reset by peer .升级到 WebSocket 后如何保持连接？

Answer 1

您应该遵循 Websocket 指南如何格式化 Websocket 发送的消息。

我认为这是一个很好的资源。我自己用过。

https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API/Writing_WebSocket_servers