Question

我的Web应用程序依赖于某个值的web.config条目（如FEATURE_ACTIVATED = true），那么如何测试读取此web.config条目的函数？

我想避免将web.config条目复制到单元测试项目中的app.config，因为需要额外的工作来同步文件。

Answer 1

拉出读取配置数据的代码，然后在测试中使用依赖注入与模拟对象或模拟框架配对。

public interface IConfiguration
{
  bool IsAwesomeFeatureActivated { get; }
}

public class Configuration: IConfiguration
{
  public bool IsAwesomeFeatureActivated
  { 
    get { /* get config value */ }
  }
}

public class AwesomeFeature
{
  private IConfiguration _configuration;

  public AwesomeFeature(IConfiguration configuration)
  {
    _configuration = configuration;
  }

  public void ExecuteFeature()
  {
    if(! _configuration.IsAwesomeFeatureActivated) return;
    // do awesome feature functionality
  }
}

public class MockConfiguration: IConfiguration
{
  private bool _isAwesomeFeatureActivated;
  public void SetIsAwesomeFeatureEnabled(bool value)
  {
    _isAwesomeFeatureActivated = value;
  }

  public bool IsAwesomeFeatureActivated
  {
    get { return _isAwesomeFeatureActivated; }
  }
}

// with mock object
[Test]
public void ExecuteFeature_WhenNotActivated_DoNothing()
{
  var mockConfig = new MockConfiguration();
  mockConfig.SetIsAwesomeFeatureActivated(false);
  var feature = new AwesomeFeature(mockConfig);
  feature.ExecuteFeature();
  Assert.SomethingHere();
}

// or with Moq framework
[Test]
public void ExecuteFeature_WithActivated_DoSomething()
{
  var mock = new Mock<IConfiguration>();
  mock.Setup(c => c.IsAwesomeFeatureActivated).Returns(true);

  var feature = new AwesomeFeature(mock.Object);
  feature.ExecuteFeature();

  Assert.SomethingHere();
}

Answer 2

我也想尽可能避免这些，但有时候没有其他选择（特别是在使用遗留代码时）。

尽可能创建用于访问配置选项的界面 - 将其注入您正在访问配置的任何位置。

然后实现一个具体的类，将其委托给内置的配置类，这是要使用的默认实现。

为测试创建接口的模拟实现，并在测试时注入。

Answer 3

我总是包装配置逻辑，以便在系统测试时替换（模拟）配置。

换句话说，我像这样包装我的配置：

    public interface IConfigurationSettings
    {
        string SmtpHost { get; }
    }

    public class ConfigurationSettings : IConfigurationSettings
    {
        public string SmtpHost
        {
            get { return ConfigurationManager.AppSettings["SmtpHost"]; }
        }
    }

    public static class Settings
    {
        private static readonly IConfigurationSettings _configurationSettings;

        static Settings()
        {
            _configurationSettings = IoCHelper.Resolve<IConfigurationSettings>();
        }

        public static string SmtpHost
        {
            get { return _configurationSettings.SmtpHost; }
        }
}

然后，当系统正在测试时，我可以像这样模拟我的配置：

var settings = new Mock<IConfigurationSettings>();
settings.SetupGet(s => s.SmtpHost).Returns("127.0.0.1");
Resolver.Setup(r => r.Resolve<IConfigurationSettings>()).Returns(settings.Object);

Visual Studio 2008 - 使用Web配置设置进行单元测试

3 个答案: