在 websocket 消息上生成 AJAX POST 会导致超时异常

Question

所以我有一个程序，基本上允许两个用户来回聊天，并通过websocket使用javascript和java服务器端点做其他事情。当其中一个用户按下按钮时，我有一个侦听器向另一个用户发出一条消息，该消息调用一个函数。在这个函数中，我希望能够使用JQuery调用AJAX POST来更新我的数据库，但这会导致java.util.concurrent.TimeoutException。知道为什么会这样吗？我想这与 websocket 连接保持打开状态的时间不足以让 ajax 调用通过这一事实有关。

所以我做了研究，我已经看到websocket和AJAX并不是完全应该混合的东西(我认为(。但是，我似乎甚至无法找到更新数据库的替代方案。这有很多代码，所以我会尝试只发布重要部分。

这是按下按钮

时的代码部分(它是一个同意按钮，因此两个用户都必须按下它，因此"**"和"--"字符(。

        fAgree.addEventListener("click", function() {
        // selects this button
        if (aStr == "**" && (yStr == "**" || oStr == "**")) {
            if (fStr == "--") {
                fStr = "*-";
                //redirect to another page
            } else if (fStr == "-*") {
                fStr = "**";

            if(secondTransaction == false) {
                    var firstCoordUpload = document.getElementById("yourPos").innerHTML;
                    var secondCoordUpload = document.getElementById("othersPos").innerHTML;
                    var firstLatUpload = parseFloat(firstCoordUpload.split(",")[0]);
                    var firstLonUpload = parseFloat(firstCoordUpload.split(",")[1]);
                    $.ajax({
                        url: "../../309/T11/setSaleData/" + getURLParameter("saleID") + "/" + firstLatUpload + "/" + firstLonUpload + "/" + firstCoordUpload + "/" + secondCoordUpload + "/" + secondSeller,
                        type: "POST",
                        headers: {
                            "Authorization" : getCredentials(),
                        },
                        success: function (result) {
                            window.location.href = '../../frontEnd/profilePage/index.html?username='+ getUsername();
                            console.log(result);
                        },
                        error: function (dc, status, err) {
                            console.log(err);
                            console.log(status);
                        }
                    });                     
            }

            }
            agreeBut.socket.send("a,f");
            htmlChange(fStr, fStar);
        }
    });

下面是在上面代码末尾调用的代码部分(agreeBut.socket.send(((。

    agreeBut.socket.onmessage = function(message) {
    // check [0]: a for agree buttons,
    // m for map,
    // l of location buttons,
    // t for trade
    var mess = message.data.split(",");
    if (mess[0] == "a") {
        // second a shows the agree button was pressed, changes aStr
        // accordingly and displays
        if (mess[1] == "a") {
            if (aStr == "--") {
                aStr = "-*";
            } else if (aStr == "*-") {
                aStr = "**";
            }
            htmlChange(aStr, aStar);
            // shows the final agree button has been pressed, changes fStr
            // accordingly and displays
        } else if (mess[1] == "f") {
            if (fStr == "--") {
                fStr = "-*";
                //redirect
            } else if (fStr == "*-") {
                fStr = "**";
                alert("on this");
                if(secondTransaction == true) {
                        alert("doing it");
                        var firstCoordUpload = document.getElementById("yourPos").innerHTML;
                        var secondCoordUpload = document.getElementById("othersPos").innerHTML;
                        var firstLatUpload = parseFloat(firstCoordUpload.split(",")[0]);
                        var firstLonUpload = parseFloat(firstCoordUpload.split(",")[1]);
                        $.ajax({
                            url: "../../309/T11/setSaleData/" + getURLParameter("saleID") + "/" + firstLatUpload + "/" + firstLonUpload + "/" + firstCoordUpload + "/" + secondCoordUpload + "/" + secondSeller,
                            type: "POST",
                            headers: {
                                "Authorization" : getCredentials(),
                            },
                            success: function (result) {
                                console.log(result);
                                alert("Got it");
                                window.location.href = '../../frontEnd/profilePage/index.html?username='+ getUsername(); 
                            },
                            error: function (dc, status, err) {
                                console.log(err);
                                console.log(status);
                            }
                        });                     
                }

                //window.location.href = '../../frontEnd/profilePage/index.html?username='+ getUsername();
            }
            htmlChange(fStr, fStar);
        }
    }
};

Answer 1

事实证明，由于在我的java服务器端点上设置了超时，我遇到了这个问题。在类中，我在会话变量上使用 setMaxIdleTimeout(0( 函数来没有空闲超时。这似乎解决了我的问题(但是我觉得这实际上只是我这边糟糕的 websocket 和 ajax 实现的解决方法(。