Question

如何在集成测试中进行依赖注入？呼叫departmentRepository或departmentAppService给我null，并在下面显示错误。

public class DepartmentAppServiceTest
{
    public SharedServicesContext context;
    public IMapper mapper;
    public IRepository<Department, int> departmentRepository;
    public IDepartmentAppService departmentAppService;

    public DepartmentAppServiceTest()
    {
        ServiceCollection services = new ServiceCollection();
        services.AddTransient<IRepository<Department>, BaseRepository<Department>>();
        services.AddTransient<IDepartmentAppService, DepartmentAppService>();

分别调用此存储库或应用程序服务的

调试和设置断点为空

新方法

 [Fact]
 var departmentDto = await departmentAppService.GetDepartmentById(2);

应用服务的构造者

DepartmentAppService(departmentRepository, mapper)
DepartmentRepository(dbcontext)

错误：

消息：System.NullReferenceException：对象引用未设置为对象的实例。

Answer 1

使用Moq，您将能够伪造违规行为，然后将其传递给您的服务。例如，您的测试方法可能类似于：

//arrange  
var company = new company() { company_name = "TCS" };  

var mockRepo = new Mock<ICompany>();  
mockRepo.Setup(x => x.InsertCompany(company)).Returns(true);  

var companyObject = new Company(mockRepo.Object);  
var retrnData = companyObject.InsertCompany(company)

此代码段摘自本文，我建议您检查一下：

https://www.c-sharpcorner.com/UploadFile/dacca2/unit-test-using-mock-object-in-dependency-injection/

Answer 2

如果使用departmentAppService局部变量，则为null。您的对象在容器中。您可以通过调用GetRequiredService或GetService方法来检索它。

我以这种方式在控制台应用程序中使用了ServiceCollection。

IServiceCollection services = new ServiceCollection();

services.AddSingleton<IDepartmentAppService, DepartmentAppService>();

using (ServiceProvider serviceProvider = services.BuildServiceProvider())
{
  var departmentAppService = serviceProvider.GetRequiredService<IDepartmentAppService>();

  await departmentAppService.GetDepartmentById(2);
}

需要注意的是，正在为每个测试用例重新创建测试类。

Answer 3

对于我们的集成测试，我们以编程方式启动应用程序，并使用HttpClient对API端点进行调用。通过这种方式，您的应用程序可以在整个启动过程中运行，并且依赖项注入就像一个魅力一样。

以下是服务器启动和客户端创建的示例，可以将它们重新用于多个测试：

_server = new TestServer(new WebHostBuilder()
                .UseEnvironment("Testing")
                .UseContentRoot(applicationPath)
                .UseConfiguration(new ConfigurationBuilder()
                    .SetBasePath(applicationPath)
                    .AddJsonFile("appsettings.json")
                    .AddJsonFile("appsettings.Testing.json")
                    .Build()
                )
                .UseStartup<TestStartup>());
_client = _server.CreateClient();
// Act
var response = await _client.GetAsync("/");

// Assert
response.EnsureSuccessStatusCode();

Microsoft也使用HttpClient对此进行了记录：
https://docs.microsoft.com/en-us/aspnet/core/test/integration-tests?view=aspnetcore-2.2

网络核心：集成测试中的依赖注入

3 个答案: