ChromeDriver异常报告“目标窗口已关闭”在无头模式下 [英] ChromeDriver exception reporting "target window already closed" in headless mode
问题描述
我正在使用xUnit，SpecFlow，Selenium和无头Chrome来运行自动化测试，但是每隔一段时间，当我尝试在 localhost 上运行时，会遇到一系列崩溃。捕获最终浏览器窗口的屏幕快照。
I am using xUnit, SpecFlow, Selenium and headless Chrome to run automated tests, but every so often I will get a series of crashes when running on localhost when trying to capture a screenshot of the final browser window.
有两种情况，每种情况都在单独的功能文件中，这意味着它们可以并行运行。似乎是第二次启动却总是失败的情况。
There are two scenarios, each in a separate feature file, which means they run in parallel. It appears to be the scenario which starts up second which always fails.
这是我创建浏览器实例的方式：
Here is how I'm creating my browser instance:
private static readonly string UserDataDir = new FileInfo(Assembly.GetExecutingAssembly().Location).DirectoryName;
var options = new ChromeOptions();
options.AddArguments("--disable-gpu");
options.AddArguments("--no-sandbox");
options.AddArgument("--ignore-certificate-errors");
options.AddArgument("--disable-web-security");
options.AddArgument("--allow-insecure-localhost");
options.AddArgument("--allow-running-insecure-content");
options.AddArgument("--acceptInsecureCerts=true");
options.AddArgument("--proxy-server='direct://'");
options.AddArgument("--proxy-bypass-list=*");
options.AddArgument("--disable-extensions");
options.AddArgument($@"--user-data-dir={UserDataDir}\prof-{ProfileCounter++}");
options.AddArgument("--incognito");
options.AddArgument("--headless");
var svc = ChromeDriverService.CreateDefaultService();
svc.Port = Randomiser.Next(29700, 29900);
Context.Driver = new ChromeDriver(svc, options, TimeSpan.FromMinutes(2));
Context.Driver.Manage().Timeouts().ImplicitWait = TimeSpan.FromSeconds(ImplicitWaitSeconds);
Context.Driver.Manage().Timeouts().PageLoad = TimeSpan.FromSeconds(PageLoadSeconds);
Context.Driver.Manage().Timeouts().AsynchronousJavaScript = TimeSpan.FromSeconds(AsynchronousJavaScriptSeconds);
这是我关闭浏览器/驱动程序的方式：
This is how I close down my browser/driver:
[AfterScenario]
public void AfterScenario()
{
Context.Driver.Quit();
Context.Driver.Dispose();
Context.Driver = null;
}
这是发生异常的地方：
Context.Driver.GetScreenshot().SaveAsFile($@"{folder}{filename}.jpg", ScreenshotImageFormat.Jpeg);
以下是输出窗格中的完整异常：
Here is the full exception from the output pane:
------ Run test started ------
NUnit Adapter 3.10.0.21: Test execution started
Running all tests in C:\git\Testing\bin\Debug\Testing.dll
NUnit couldn't find any tests in C:\git\Testing\bin\Debug\Testing.dll
NUnit Adapter 3.10.0.21: Test execution complete
[xUnit.net 00:00:00.5180673] Discovering: Testing
[xUnit.net 00:00:01.0205999] Discovered: Testing
[xUnit.net 00:00:01.0244487] Starting: Testing
[xUnit.net 00:00:14.7836328] View the Daring Fireball talk show [FAIL]
[xUnit.net 00:00:14.7874843] OpenQA.Selenium.NoSuchWindowException : no such window: target window already closed
from unknown error: web view not found
(Session info: headless chrome=65.0.3325.181)
(Driver info: chromedriver=2.38.551601 (edb21f07fc70e9027c746edd3201443e011a61ed),platform=Windows NT 6.1.7601 SP1 x86_64)
[xUnit.net 00:00:14.7898949] Stack Trace:
[xUnit.net 00:00:14.7911454] at OpenQA.Selenium.Remote.RemoteWebDriver.UnpackAndThrowOnError(Response errorResponse)
[xUnit.net 00:00:14.7916551] at OpenQA.Selenium.Remote.RemoteWebDriver.Execute(String driverCommandToExecute, Dictionary`2 parameters)
[xUnit.net 00:00:14.7923841] at OpenQA.Selenium.Remote.RemoteWebDriver.GetScreenshot()
[xUnit.net 00:00:14.7929467] C:\git\Testing\StepDefinitions\Common\Implementation\PageNavigationStepsImplementation.cs(90,0): at Testing.StepDefinitions.Common.Implementation.PageNavigationStepsImplementation.TakeScreenshot(String filename)
[xUnit.net 00:00:14.7933710] C:\git\Testing\StepDefinitions\FeatureProperties.cs(122,0): at Testing.StepDefinitions.FeatureProperties.AfterScenario()
[xUnit.net 00:00:14.7939053] at lambda_method(Closure , IContextManager )
[xUnit.net 00:00:14.7944826] at TechTalk.SpecFlow.Bindings.BindingInvoker.InvokeBinding(IBinding binding, IContextManager contextManager, Object[] arguments, ITestTracer testTracer, TimeSpan& duration)
[xUnit.net 00:00:14.7949636] at TechTalk.SpecFlow.Infrastructure.TestExecutionEngine.InvokeHook(IBindingInvoker invoker, IHookBinding hookBinding, HookType hookType)
[xUnit.net 00:00:14.7956197] at TechTalk.SpecFlow.Infrastructure.TestExecutionEngine.FireEvents(HookType hookType)
[xUnit.net 00:00:14.7960898] at TechTalk.SpecFlow.Infrastructure.TestExecutionEngine.FireScenarioEvents(HookType bindingEvent)
[xUnit.net 00:00:14.7966550] at TechTalk.SpecFlow.Infrastructure.TestExecutionEngine.OnScenarioEnd()
[xUnit.net 00:00:14.7971662] at TechTalk.SpecFlow.TestRunner.OnScenarioEnd()
[xUnit.net 00:00:14.7975471] at SpecFlow.xUnitAdapter.SpecFlowPlugin.Runners.ScenarioTestCaseRunner.RunScenario(SpecFlowDocument gherkinDocument, Scenario scenario)
[xUnit.net 00:00:14.7979477] at SpecFlow.xUnitAdapter.SpecFlowPlugin.Runners.ScenarioTestCaseRunner.<>c__DisplayClass9_0.<RunTestAsync>b__2()
[xUnit.net 00:00:14.7990766] Output:
[xUnit.net 00:00:14.7995180] Given I am on the https://daringfireball.net/ page
[xUnit.net 00:00:14.7998653] -> done: PageNavigationSteps.IAmOnThePage("https://daringfir...") (11.5s)
[xUnit.net 00:00:14.8002840] When I click element THE TALK SHOW found by text
[xUnit.net 00:00:14.8006231] -> error: no such window: target window already closed
from unknown error: web view not found
(Session info: headless chrome=65.0.3325.181)
(Driver info: chromedriver=2.38.551601 (edb21f07fc70e9027c746edd3201443e011a61ed),platform=Windows NT 6.1.7601 SP1 x86_64)
[xUnit.net 00:00:14.8009870] Then I arrive on the page titled Daring Fireball: The Talk Show
[xUnit.net 00:00:14.8013918] -> skipped because of previous errors
[xUnit.net 00:00:18.8364913] Finished: Testing
========== Run test finished: 3 run (0:00:20.3) ==========
更新
步骤代码：
[When(@"I click element (.*)")]
public void IClickElement(string id)
{
try {
Context.Driver.FindElementsByPartialLinkText(id).FirstOrDefault();
} catch (Exception ex) {
var mssg = ex.Message; // debugger stops here (see exception below)
}
}
AfterScenario代码：
AfterScenario code:
[AfterScenario]
public void AfterScenario()
{
Context.Driver.Quit();
Context.Driver.Dispose();
Context.Driver = null;
Context.NgDriver = null;
}
虚假的，不规则的错误消息：
Spurious, irregular error message:
no such window: target window already closed
from unknown error: web view not found
(Session info: headless chrome=65.0.3325.181)
(Driver info: chromedriver=2.38.551601 (edb21f07fc70e9027c746edd3201443e011a61ed),platform=Windows NT 6.1.7601 SP1 x86_64)
关联的堆栈跟踪：
at OpenQA.Selenium.Remote.RemoteWebDriver.UnpackAndThrowOnError(Response errorResponse)
at OpenQA.Selenium.Remote.RemoteWebDriver.Execute(String driverCommandToExecute, Dictionary`2 parameters)
at OpenQA.Selenium.Remote.RemoteWebDriver.FindElements(String mechanism, String value)
at OpenQA.Selenium.Remote.RemoteWebDriver.FindElementsByPartialLinkText(String partialLinkText)
at Testing.StepDefinitions.Common.Implementation.GenericNavigationStepsImplementations.FindElement(Matcher match, String id, String attributeValue) in C:\git\Testing\Testing\StepDefinitions\Common\Implementation\GenericNavigationStepsImplementations.cs:line 73
AfterScenario没有任何问题，但是通过删除屏幕快照尝试，它不再抛出。在步骤定义的捕获中放置一个停止点表明浏览器已关闭。
AfterScenario does not have any catching but with the removal of the screenshot attempt, it no longer throws. Putting a stop point in the catch of the step definition shows that the browser has been closed.
UPDATE 2
已将Chrome更新到66。异常消息：
Updated Chrome to 66. Exception message:
no such window: target window already closed
from unknown error: web view not found
(Session info: headless chrome=66.0.3359.117)
(Driver info: chromedriver=2.38.551601 (edb21f07fc70e9027c746edd3201443e011a61ed),platform=Windows NT 6.1.7601 SP1 x86_64)
堆栈跟踪：
at OpenQA.Selenium.Remote.RemoteWebDriver.UnpackAndThrowOnError(Response errorResponse)
at OpenQA.Selenium.Remote.RemoteWebDriver.Execute(String driverCommandToExecute, Dictionary`2 parameters)
at OpenQA.Selenium.Remote.RemoteWebDriver.FindElements(String mechanism, String value)
at OpenQA.Selenium.Remote.RemoteWebDriver.FindElementsByPartialLinkText(String partialLinkText)
at Testing.StepDefinitions.Common.Implementation.GenericNavigationStepsImplementations.FindElement(Matcher match, String id, String attributeValue) in C:\git\Testing\Testing\StepDefinitions\Common\Implementation\GenericNavigationStepsImplementations.cs:line 73
使用相同代码的相同错误。
The same error with the same code.
推荐答案
如上所述，问题可能是由于多种原因造成的
As discussed the issue could be because of multiple reasons
-
svc.Port = Randomiser.Next（29700，29900）;。您永远不要自己分配端口，它也可能与其他程序端口冲突，甚至可能会随机生成相同的端口号，这将导致问题
svc.Port = Randomiser.Next(29700, 29900);. You should never assign the port yourself, it can be conflicting with some other program port as well and even the same port number can be generated in random which will cause the issue
您正在并行启动脚本。在极少数情况下，驾驶员启动时可能会出现竞争状况，并且驾驶员可能无法启动。因此，我可以将Factory模式添加到我的驱动程序初始化代码中，如下所示：
You are launching scripts in parallel. In rare cases there could be a race condition in driver launch and the driver may fail to launch. So I would add Factory pattern to my driver initialization code like below
public sealed class ChromeFactory
{
private static readonly object padlock = new object();
ChromeFactory()
{
}
public static WebDriver NewInstance
{
get
{
lock (padlock)
{
return new ChromeDriver();
}
}
}
}
并按如下所示初始化驱动程序
And initialize the driver like below
Context.Driver = ChromeFactory.NewInstance
- 由于您具有并行执行功能，因此我建议不要使用使用＃2建议，在浏览器限制计数中设置硒网格并使用它。
这篇关于ChromeDriver异常报告“目标窗口已关闭”在无头模式下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！
