在 Mozilla 上通过随机 Selenium webdriver 失败

Question

我正在为使用 Angular 2 编写的网站编写测试脚本。我正在使用 Selenium 2.53.1 和 Mozilla 45.0、Junit 4.12

我有相同的测试通过，然后在 20 分钟后执行时同样的测试没有通过。我将所有函数保存在一个超类中，并将测试用例保存在从它继承的类中。

这是失败跟踪：

org.openqa.selenium.TimeoutException: Timed out after 10 seconds waiting for element to be clickable: By.id: priceSheet
Build info: version: '2.53.1', revision: 'a36b8b1', time: '2016-06-30 17:32:46'
System info: host: 'VP1240940', ip: '10.12.50.247', os.name: 'Windows 7', os.arch: 'amd64', os.version: '6.1', java.version: '1.8.0_121'
Driver info: org.openqa.selenium.firefox.FirefoxDriver
Capabilities [{applicationCacheEnabled=true, rotatable=false, handlesAlerts=true, databaseEnabled=true, version=45.0, platform=WINDOWS, nativeEvents=false, acceptSslCerts=true, webStorageEnabled=true, locationContextEnabled=true, browserName=firefox, takesScreenshot=true, javascriptEnabled=true, cssSelectorsEnabled=true}]
Session ID: 5e182ec9-8d39-499e-b05f-fc66f054f140
    at org.openqa.selenium.support.ui.WebDriverWait.timeoutException(WebDriverWait.java:80)
    at org.openqa.selenium.support.ui.FluentWait.until(FluentWait.java:261)
    at lieuxBatimentsMontreal.test.WebElements.confirmTarifsChange(WebElements.java:412)
    at lieuxBatimentsMontreal.test.ModifierUnBatiment.ModifierLeTarif(ModifierUnBatiment.java:123)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
Caused by: org.openqa.selenium.NoSuchElementException: Unable to locate element: {"method":"id","selector":"priceSheet"}
Command duration or timeout: 15.08 seconds
For documentation on this error, please visit: http://seleniumhq.org/exceptions/no_such_element.html
Build info: version: '2.53.1', revision: 'a36b8b1', time: '2016-06-30 17:32:46'
System info: host: 'VP1240940', ip: '10.12.50.247', os.name: 'Windows 7', os.arch: 'amd64', os.version: '6.1', java.version: '1.8.0_121'
Driver info: org.openqa.selenium.firefox.FirefoxDriver
Capabilities [{applicationCacheEnabled=true, rotatable=false, handlesAlerts=true, databaseEnabled=true, version=45.0, platform=WINDOWS, nativeEvents=false, acceptSslCerts=true, webStorageEnabled=true, locationContextEnabled=true, browserName=firefox, takesScreenshot=true, javascriptEnabled=true, cssSelectorsEnabled=true}]
Session ID: 5e182ec9-8d39-499e-b05f-fc66f054f140
*** Element info: {Using=id, value=priceSheet}
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at org.openqa.selenium.remote.ErrorHandler.createThrowable(ErrorHandler.java:206)
    at org.openqa.selenium.remote.ErrorHandler.throwIfResponseFailed(ErrorHandler.java:158)
    at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:678)
    at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:363)
    at org.openqa.selenium.remote.RemoteWebDriver.findElementById(RemoteWebDriver.java:413)
    at org.openqa.selenium.By$ById.findElement(By.java:218)
    at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:355)
    at org.openqa.selenium.support.ui.ExpectedConditions.findElement(ExpectedConditions.java:899)
    at org.openqa.selenium.support.ui.ExpectedConditions.access$0(ExpectedConditions.java:897)
    at org.openqa.selenium.support.ui.ExpectedConditions$7.apply(ExpectedConditions.java:205)
    at org.openqa.selenium.support.ui.ExpectedConditions$7.apply(ExpectedConditions.java:1)
    at org.openqa.selenium.support.ui.ExpectedConditions$22.apply(ExpectedConditions.java:653)
    at org.openqa.selenium.support.ui.ExpectedConditions$22.apply(ExpectedConditions.java:1)
    at org.openqa.selenium.support.ui.FluentWait.until(FluentWait.java:238)
    ... 27 more
Caused by: org.openqa.selenium.NoSuchElementException: Unable to locate element: {"method":"id","selector":"priceSheet"}
For documentation on this error, please visit: http://seleniumhq.org/exceptions/no_such_element.html
Build info: version: '2.53.1', revision: 'a36b8b1', time: '2016-06-30 17:32:46'
System info: host: 'VP1240940', ip: '10.12.50.247', os.name: 'Windows 7', os.arch: 'amd64', os.version: '6.1', java.version: '1.8.0_121'
Driver info: driver.version: unknown
    at <anonymous class>.FirefoxDriver.prototype.findElementInternal_(file:///C:/Users/xtoumni/AppData/Local/Temp/anonymous4418321286959635118webdriver-profile/extensions/fxdriver@googlecode.com/components/driver-component.js:10770)
    at <anonymous class>.fxdriver.Timer.prototype.setTimeout/<.notify(file:///C:/Users/xtoumni/AppData/Local/Temp/anonymous4418321286959635118webdriver-profile/extensions/fxdriver@googlecode.com/components/driver-component.js:625)

ID 在那里。相同的测试用例在几分钟前通过...

如果有人以前遇到过这个问题，请告诉我。它需要超级稳定，因为这些测试将包含在 Jenkins 流程中。新版本的部署将取决于我的测试。

Answer 1

    public String confirmTarifsChange(){
    String tarifs;
    WebDriverWait wait_element = new WebDriverWait(driver1, 40);
    WebElement anElement = wait_element.until(ExpectedConditions.elementToBeClickable(By.id("priceSheet")));
    tarifs = anElement.getText();
    return tarifs;

}

我使用了这段代码，但仍然不能以稳定的方式工作。我还有一些问题。 我没有使用 Action，因为这个函数需要使用通常的 getText() 返回一个字符串，但它在 Action 库中不可用。

@MikeJRamsey56

Answer 2

Selenium 无法判断所有 JavaScript 何时完成加载 DOM。因此，每个 selenium 程序员都需要一个策略来确定何时可以安全地继续。对于 Angular，我做了两件事：

A.等待 Browser ReadyState=complete。

public void waitForBrowserReadystateComplete(WebDriver webDriver) {
    for (int a=0; a<20; a++) {
        JavascriptExecutor javascriptExecutor = (JavascriptExecutor) webDriver;
        if (javascriptExecutor.executeScript("return document.readyState")
                .toString().equals("complete")) {
            break;
        }
        sleepResponsibly(500);
    }
}

public void sleepResponsibly(int timeMillisecond){
    try{
        Thread.sleep(timeMillisecond);
    } catch (InterruptedException ex) {
        Thread.currentThread().interrupt(); 
        throw new RuntimeException(ex);
    }
}

B.等待 Angular 完成加载 DOM

public boolean waitForAngularToLoad(WebDriver driver, int timeout) {
    driver.manage().timeouts().setScriptTimeout(timeout, TimeUnit.SECONDS);
    WebDriverWait wait = new WebDriverWait(driver, timeout, 500L);
    return wait.until(angularHasFinishedProcessing());
}


public static ExpectedCondition<Boolean> angularHasFinishedProcessing() {
    return new ExpectedCondition<Boolean>() {
        @Override
        public Boolean apply(WebDriver driver) {
            String hasAngularFinishedScript = "var callback = arguments[arguments.length - 1];\n" +
                    "var el = document.querySelector('html');\n" +
                    "if (!window.angular) {\n" +
                    "    callback('false')\n" +
                    "}\n" +
                    "if (angular.getTestability) {\n" +
                    "    angular.getTestability(el).whenStable(function(){callback('true')});\n" +
                    "} else {\n" +
                    "    if (!angular.element(el).injector()) {\n" +
                    "        callback('false')\n" +
                    "    }\n" +
                    "    var browser = angular.element(el).injector().get('$browser');\n" +
                    "    browser.notifyWhenNoOutstandingRequests(function(){callback('true')});\n" +
                    "}";

            JavascriptExecutor javascriptExecutor = (JavascriptExecutor) driver;
            String isProcessingFinished = javascriptExecutor.executeAsyncScript(hasAngularFinishedScript).toString();

            return Boolean.valueOf(isProcessingFinished);
        }
    };
}

在您的具体情况下，我将编写以下代码：

WebDriverWait wait_element = new WebDriverWait(driver, 40);
WebElement anElement = wait_element.until(ExpectedConditions.elementToBeClickable(By.id("priceSheet")));

Actions action = new Actions(driver);
action.moveToElement(anElement).click().build().perform();

处理许多特殊情况（例如滚动），但不是全部（例如加载旋转器覆盖 anElement 并吸收点击）。但它比简单的点击更可靠。