并行运行所有测试失败，会话 ID 无效

Question

我在一个测试类中有 4 个测试，当我分别运行每个测试时，它们都通过了。但是，当我并行运行它们时，它们会失败。我相信问题在于使用相同的驱动程序实例进行测试。我已将驱动程序更改为受保护，但结果是一样的。并行测试失败。

WebDriver 类：

using OpenQA.Selenium;

namespace TestAutomationFramework.Utilities
{
    public class WebDriver
    {
        protected IWebDriver Driver { get; set; }

    }
}

TestSetup 类：

using System;
using NUnit.Framework;
using OpenQA.Selenium.Chrome;
using OpenQA.Selenium.Remote;
using TestAutomationFramework.Utilities;

namespace TestAutomationFramework.Tests
{
    [TestFixture]
    public class TestSetup : WebDriver
    {
        public TestSetup()
        {
            var options = new ChromeOptions();
            Driver = new RemoteWebDriver(new Uri("http://localhost:4444/wd/hub"), options.ToCapabilities(), TimeSpan.FromSeconds(10));
            Driver.Manage().Window.Maximize();
        }

        // Test Setup, every test starts with this method
        [SetUp]
        public void StartTest()
        {
            Driver.Navigate().GoToUrl("https://google.com");
        }

        // Test Tear Down, every test ends with this method
        [TearDown]
        public void QuitTest()
        {
            Driver.Close();
            Driver.Quit();
        }
    }
}

BasePage 类：

using System.Threading;
using OpenQA.Selenium;

namespace TestAutomationFramework.Pages
{
    public class BasePage
    {
        protected IWebDriver WebDriver;
        public BasePage(IWebDriver webDriver) => WebDriver = webDriver;

        #region Elements
        private IWebElement SearchField => WebDriver.FindElement(By.Name("q"));
        private IWebElement SearchButton => WebDriver.FindElement(By.Name("btnK"));

        #endregion

        public void SearchFor(string searchText)
        {
            //Thread.Sleep(2000);
            SearchField.SendKeys(searchText);
            SearchButton.Click();
            Thread.Sleep(5000);
        }

        public bool SearchResultShows(string whatShows)
        {
            Thread.Sleep(5000);
            var element = WebDriver.FindElement(By.XPath(
                "//*[@id='rhs_block']/div/div[1]/div/div[1]/div[2]/div[1]/div[2]/div[2]/div/div/div[2]/div/span"));
            return element.Text.Equals(whatShows);
        }
    }
}

DemoTest 类

using NUnit.Framework;
using TestAutomationFramework.Pages;

namespace TestAutomationFramework.Tests
{
    [TestFixture]
    [Parallelizable(ParallelScope.All)]
    public class DemoTest : TestSetup
    {
        private BasePage _basePage;

        [Test]
        public void TestLogin()
        {
            const string query = "Test automation";
            _basePage = new BasePage(webDriver: Driver);
            _basePage.SearchFor(query);
            var shows = _basePage.SearchResultShows(whatShows: query);
            Assert.IsTrue(shows);
        }

        [Test]
        public void TestLogin2()
        {
            const string query = "Test automation";
            _basePage = new BasePage(webDriver: Driver);
            _basePage.SearchFor(query);
            var shows = _basePage.SearchResultShows(whatShows: query);
            Assert.IsTrue(shows);
        }

        [Test]
        public void TestLogin3()
        {
            const string query = "Test automation";
            _basePage = new BasePage(webDriver: Driver);
            _basePage.SearchFor(query);
            var shows = _basePage.SearchResultShows(whatShows: query);
            Assert.IsTrue(shows);
        }

        [Test]
        public void TestLogin4()
        {
            const string query = "Test automation";
            _basePage = new BasePage(webDriver: Driver);
            _basePage.SearchFor(query);
            var shows = _basePage.SearchResultShows(whatShows: query);
            Assert.IsTrue(shows);
        }
    }
}

问题：如何解决驱动实例，使所有测试不使用同一个驱动？

Answer 1

根据Does NUnit create a new instance of the test fixture class for each contained test method nowadays?，测试类实例对于所有测试都是相同的。 Driver 实例在第一个测试运行后立即被销毁（在方法 QuitTest 中），因此另一个测试将不再有驱动程序。

试试这个：

[TestFixture]
public class TestSetup
{
   private ThreadLocal<IWebDriver> _driver;

   protected IWebDriver Driver => _driver.Value;

   // Test Setup, every test starts with this method
   [SetUp]
   public void StartTest()        
   {
       var options = new ChromeOptions();
       _driver = new ThreadLocal<IWebDriver>(() => new RemoteWebDriver(new Uri("http://localhost:4444/wd/hub"), options.ToCapabilities(), TimeSpan.FromSeconds(10)));
       Driver.Manage().Window.Maximize();
       Driver.Navigate().GoToUrl("https://google.com");
   }

   // Test Tear Down, every test ends with this method
   [TearDown]
   public void QuitTest()
   {
       Driver.Close();
       Driver.Quit();
       _driver.Dispose();
   }
}

这可能会因为TheadLocal 而影响性能。我不确定。

Answer 2

您始终可以使用驱动程序制作字典，其中键是线程 ID，值是测试使用的驱动程序。

private static Dictionary<int, IWebDriver> drivers = new Dictionary<int, IWebDriver();

public static IWebDriver GetDriver()
{
    int id = Thread.CurrentThread.ManagedThreadId;
    if (!drivers.Keys.Contains(id))
    {
        SetupNewDriver();
    }
    return drivers[id];
}

在创建驱动程序时将其添加到字典中（下一行来自 SetupDriver 方法）：

drivers.Add(Thread.CurrentThread.ManagedThreadId, driver);

在我的项目中，我使用上面的代码创建了类 DriverManager，它可以工作。缺点是您将无法为一项测试运行多个驱动程序。有可能为驱动程序制作更复杂的结构，但我不需要这样做。