Websocket onerror - 如何读取错误描述？

Question

我一直在开发基于浏览器的多人游戏一段时间,我一直在各种环境(客户办公室,公共wifi等)测试不同的端口可访问性.一切都很顺利,除了一件事:我无法弄清楚如何读取错误号.或收到onerror事件时的描述.

客户端websocket是在javascript中完成的.

例如:

// Init of websocket
websocket = new WebSocket(wsUri);
websocket.onerror = OnSocketError;
...etc...

// Handler for onerror:
function OnSocketError(ev)
{
    output("Socket error: " + ev.data);
}

'output'只是一些写入div的实用函数.

我得到的是ev.data的'undefined'.总是.我一直在谷歌搜索,但似乎没有关于这个事件有什么参数以及如何正确阅读它的规范.

任何帮助表示赞赏!

Answer 1

除了nmaier的回答,正如他所说,你将始终收到代码1006.但是,如果您在某种程度上理论上接收其他代码,则此处是显示结果的代码(通过RFC6455).

你几乎永远不会在实践中得到这些代码,所以这段代码几乎没有意义

var websocket;
if ("WebSocket" in window)
{
    websocket = new WebSocket("ws://yourDomainNameHere.org/");

    websocket.onopen = function (event) {
        $("#thingsThatHappened").html($("#thingsThatHappened").html() + "<br />" + "The connection was opened");
    };
    websocket.onclose = function (event) {
        var reason;
        alert(event.code);
        // See http://tools.ietf.org/html/rfc6455#section-7.4.1
        if (event.code == 1000)
            reason = "Normal closure, meaning that the purpose for which the connection was established has been fulfilled.";
        else if(event.code == 1001)
            reason = "An endpoint is \"going away\", such as a server going down or a browser having navigated away from a page.";
        else if(event.code == 1002)
            reason = "An endpoint is terminating the connection due to a protocol error";
        else if(event.code == 1003)
            reason = "An endpoint is terminating the connection because it has received a type of data it cannot accept (e.g., an endpoint that understands only text data MAY send this if it receives a binary message).";
        else if(event.code == 1004)
            reason = "Reserved. The specific meaning might be defined in the future.";
        else if(event.code == 1005)
            reason = "No status code was actually present.";
        else if(event.code == 1006)
           reason = "The connection was closed abnormally, e.g., without sending or receiving a Close control frame";
        else if(event.code == 1007)
            reason = "An endpoint is terminating the connection because it has received data within a message that was not consistent with the type of the message (e.g., non-UTF-8 [http://tools.ietf.org/html/rfc3629] data within a text message).";
        else if(event.code == 1008)
            reason = "An endpoint is terminating the connection because it has received a message that \"violates its policy\". This reason is given either if there is no other sutible reason, or if there is a need to hide specific details about the policy.";
        else if(event.code == 1009)
           reason = "An endpoint is terminating the connection because it has received a message that is too big for it to process.";
        else if(event.code == 1010) // Note that this status code is not used by the server, because it can fail the WebSocket handshake instead.
            reason = "An endpoint (client) is terminating the connection because it has expected the server to negotiate one or more extension, but the server didn't return them in the response message of the WebSocket handshake. <br /> Specifically, the extensions that are needed are: " + event.reason;
        else if(event.code == 1011)
            reason = "A server is terminating the connection because it encountered an unexpected condition that prevented it from fulfilling the request.";
        else if(event.code == 1015)
            reason = "The connection was closed due to a failure to perform a TLS handshake (e.g., the server certificate can't be verified).";
        else
            reason = "Unknown reason";

        $("#thingsThatHappened").html($("#thingsThatHappened").html() + "<br />" + "The connection was closed for reason: " + reason);
    };
    websocket.onmessage = function (event) {
        $("#thingsThatHappened").html($("#thingsThatHappened").html() + "<br />" + "New message arrived: " + event.data);
    };
    websocket.onerror = function (event) {
        $("#thingsThatHappened").html($("#thingsThatHappened").html() + "<br />" + "There was an error with your websocket.");
    };
}
else
{
    alert("Websocket is not supported by your browser");
    return;
}

websocket.send("Yo wazzup");

websocket.close();

见http://jsfiddle.net/gr0bhrqr/

Answer 2

该错误Event的onerror处理程序接收不含有这种信息的简单事件:

如果要求用户代理使WebSocket连接失败,或者使用偏见关闭WebSocket连接,则在WebSocket对象上触发名为error的简单事件.

你可能有更好的运气来监听这个close事件,它CloseEvent确实是一个CloseEvent.code包含根据RFC 6455 11.7的数字代码和CloseEvent.reason字符串属性的属性.

但请注意,CloseEvent.code(和CloseEvent.reason)受限于避免网络探测和其他安全问题.