如何检查来自浏览器的待处理请求（Ajax及其变体） [英] How to checkif there are pending requests (Ajax and its variants) from browser

问题描述

我处理的一些网站有大量的ajax请求。我打算在点击断言元素之前等待Ajax请求完成。目前我使用

Some of the sites I deal with have heavy ajax requests. I plan to wait for Ajax request completion before clicking for asserting for element. Currently I use

try {
    if (driver instanceof JavascriptExecutor) {
        JavascriptExecutor jsDriver = (JavascriptExecutor)driver;

        for (int i = 0; i< timeoutInSeconds; i++) 
        {
            Object numberOfAjaxConnections = jsDriver.executeScript("return jQuery.active");
            // return should be a number
            if (numberOfAjaxConnections instanceof Long) {
                Long n = (Long)numberOfAjaxConnections;
                System.out.println("Number of active jquery ajax calls: " + n);
                if (n.longValue() == 0L)  break;
            }
            Thread.sleep(1000);
        }
    }
    else {
       System.out.println("Web driver: " + driver + " cannot execute javascript");
    }
}
catch (InterruptedException e) {
    System.out.println(e);
}

但它适用于Ajax请求，但不适用于任何类似的变体请求jQuery库。

But it works well for Ajax requests but not for any similar requests with variants of jQuery libraries.

注意：

document.readyState == 'complete'

它不适用于Ajax请求或任何其他类似的替代方案。

It doesn't work for Ajax requests or any other similar alternatives.

这些测试都不是由我编写的，也不属于单个webapp。所以我无法编辑webapp。

Neither tests are written by me or belong to single webapp. So I can't edit the webapp.

推荐答案

我找到了答案，它适用于少数Ajax和非ajax网站我检查。在这个补丁后，我不再需要对ajax重页进行隐式等待，LeGac在他对该问题的一个评论中指出了以下代码。

I found the answer and it worked for few Ajax and non-ajax sites I checked. After this patch I no longer need to do implicit waits even for ajax heavy pages, LeGac pointed out the following code in one of his comments to the question.

public static void checkPendingRequests(FirefoxDriver driver) {
    int timeoutInSeconds = 5;
    try {
        if (driver instanceof JavascriptExecutor) {
            JavascriptExecutor jsDriver = (JavascriptExecutor)driver;

            for (int i = 0; i< timeoutInSeconds; i++) 
            {
                Object numberOfAjaxConnections = jsDriver.executeScript("return window.openHTTPs");
                // return should be a number
                if (numberOfAjaxConnections instanceof Long) {
                    Long n = (Long)numberOfAjaxConnections;
                    System.out.println("Number of active calls: " + n);
                    if (n.longValue() == 0L)  break;
                } else{
                    // If it's not a number, the page might have been freshly loaded indicating the monkey
                    // patch is replaced or we haven't yet done the patch.
                    monkeyPatchXMLHttpRequest(driver);
                }
                Thread.sleep(1000);
            }
        }
        else {
           System.out.println("Web driver: " + driver + " cannot execute javascript");
        }
    }
    catch (InterruptedException e) {
        System.out.println(e);
    }    
}



public static void monkeyPatchXMLHttpRequest(FirefoxDriver driver) {
    try {
        if (driver instanceof JavascriptExecutor) {
            JavascriptExecutor jsDriver = (JavascriptExecutor)driver;
            Object numberOfAjaxConnections = jsDriver.executeScript("return window.openHTTPs");
            if (numberOfAjaxConnections instanceof Long) {
                return;
            }
            String script = "  (function() {" +
                "var oldOpen = XMLHttpRequest.prototype.open;" +
                "window.openHTTPs = 0;" +
                "XMLHttpRequest.prototype.open = function(method, url, async, user, pass) {" +
                "window.openHTTPs++;" +
                "this.addEventListener('readystatechange', function() {" +
                "if(this.readyState == 4) {" +
                "window.openHTTPs--;" +
                "}" +
                "}, false);" +
                "oldOpen.call(this, method, url, async, user, pass);" +
                "}" +
                "})();";
            jsDriver.executeScript(script);
        }
        else {
           System.out.println("Web driver: " + driver + " cannot execute javascript");
        }
    }
    catch (Exception e) {
        System.out.println(e);
    }
}

每一步都需要调用

checkPendingRequests(driver);

这篇关于如何检查来自浏览器的待处理请求（Ajax及其变体）的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！