To navigate this series, you can visit ASP.NET Core Testing<\/a>.<\/p>\n Let\u2019s move on.<\/p>\n Integration testing ensures that different components inside the application function correctly when working together.<\/strong> The main difference between integration testing and unit testing is that integration testing often includes an application’s infrastructure components like a database, file system, etc. When we work with unit tests, we mock these components. But with integration testing, we want to ensure that the whole app is working as expected with all of these components combined.<\/p>\n So, let’s see how we can write integration tests in ASP.NET Core.<\/p>\n First, we are going to create a new After the project creation, we are going to rename the Additionally, we are going to reference the main project<\/strong> and install two NuGet packages required for testing purposes:<\/p>\n Now we can continue on.<\/p>\n The So, let’s see how we can use the WebApplicationFactory class in .NET 6 to create an in-memory factory configuration.\u00a0<\/p>\n The first thing we are going to do is to create a new class For this to work, we need two namespaces included:<\/p>\n Our class implements the But we have a small problem. Our class doesn’t recognize the After this modification, our issue will disappear in the After we’ve fixed our issue, we can implement the A couple of things to mention here.<\/p>\n In the After that, we add the database context to the service container and instruct it to use the in-memory database instead of the real database.<\/p>\n Finally, we ensure that we seed the data from the With these preparations in place, we can return to the test class and start writing our tests.<\/p>\n In our test class, we can find a single test method with the default name. But let\u2019s remove it and start from scratch.<\/p>\n The first thing we have to do is to implement a previously created So, we implement the Now, let’s write our first integration test:<\/p>\n We use the If it is false, it means that the request is not successful, and the test will fail.<\/p>\n Finally, we serialize our HTTP content to a string using the Right now, if we start the test runner, our test will fail due to the migration issue:<\/p>\n That’s because our Now, we can run our test:<\/p>\n We can see that the test passed and that we successfully returned our employees from the in-memory database. If you want to ensure that we are really using the in-memory database and not the real one, you can always stop the SQLServer service in the Services window and run the test again.<\/p>\n Excellent!<\/p>\n Now, we can continue towards the integration testing of both Before we continue with testing, let\u2019s open the Great.<\/p>\n Now, we are ready to write our test code.<\/p>\n We want to verify when the Create (GET) action executes, it returns a create form:<\/p>\n And it does.<\/p>\n To continue, we will write some integration testing code for the POST action. For the first test method, we will verify that our action returns a view with an appropriate error message when the model sent from the That said, let\u2019s write the test code:<\/p>\n We create a post request and the After that, we store the Finally, we serialize our response and verify assertions.<\/p>\n If we take a look at the That is exactly what we verify in our test method.<\/p>\n Now, we can run the Test Explorer:<\/p>\n Well, this test fails. But there is nothing wrong with the code; the test code is good. For some reason, we are getting the 400 Bad Request message.<\/p>\n Why is that?<\/p>\nWhat is Integration Testing?<\/h2>\n
Preparing a new Project for Integration Testing<\/span><\/h2>\n
xUnit<\/code> project named EmployeesApp.IntegrationTests<\/code> for integration testing purposes.<\/p>\nUnitTest1.cs<\/code> class to EmployeesControllerIntegrationTests<\/code>.<\/p>\n\n
WebApplicationFactory<\/code> to help us bootstrap our app in-memory<\/li>\nUsing WebApplicationFactory class for Creating In-Memory Factory Configuration<\/span><\/h2>\n
WebApplicationFactory<\/code> class is a factory that we can use to bootstrap an application in memory for functional end-to-end tests. With .NET 6, new templates were introduced without the Startup<\/code> class. This affects the implementation of WebApplicationFactory<\/code> class compared to what we used to in .NET 5.\u00a0\u00a0<\/p>\nTestingWebAppFactory<\/code> and modify it:<\/p>\npublic class TestingWebAppFactory<TEntryPoint> : WebApplicationFactory<Program> where TEntryPoint : Program\r\n{\r\n protected override void ConfigureWebHost(IWebHostBuilder builder)\r\n {\r\n \r\n }\r\n}<\/pre>\nusing Microsoft.AspNetCore.Hosting;\r\nusing Microsoft.AspNetCore.Mvc.Testing;<\/pre>\n
WebApplicationFactory<Startup><\/code> class and overrides the ConfigureWebHost<\/code> method, which allows us to configure the application before it gets built.<\/p>\nProgram<\/code> class even though we have the reference from the main project. That’s because in .NET 6 compiler generates the Program<\/code> class behind the scenes as the internal class, thus making it inaccessible in our integration testing project. So to solve this, we can create a public partial Program<\/code> class in the Program.cs file<\/strong> in the main project:<\/p>\napp.Run();\r\n\r\npublic partial class Program { }<\/pre>\nTestWebAppFactory<\/code> class.<\/p>\nImplementation of the ConfigureWebHost Method<\/h3>\n
ConfigureWebHost<\/code> method:<\/p>\npublic class TestingWebAppFactory<TEntryPoint> : WebApplicationFactory<Program> where TEntryPoint : Program\r\n{\r\n protected override void ConfigureWebHost(IWebHostBuilder builder)\r\n {\r\n builder.ConfigureServices(services =>\r\n {\r\n var descriptor = services.SingleOrDefault(\r\n d => d.ServiceType ==\r\n typeof(DbContextOptions<EmployeeContext>));\r\n\r\n if (descriptor != null)\r\n services.Remove(descriptor);\r\n\r\n services.AddDbContext<EmployeeContext>(options =>\r\n {\r\n options.UseInMemoryDatabase(\"InMemoryEmployeeTest\");\r\n });\r\n\r\n var sp = services.BuildServiceProvider();\r\n using (var scope = sp.CreateScope())\r\n using (var appContext = scope.ServiceProvider.GetRequiredService<EmployeeContext>())\r\n {\r\n try\r\n {\r\n appContext.Database.EnsureCreated();\r\n }\r\n catch (Exception ex)\r\n {\r\n \/\/Log errors or do anything you think it's needed\r\n throw;\r\n }\r\n }\r\n });\r\n }\r\n}<\/pre>\nConfigureWebHost<\/code> method, we remove the EmployeeContext registration from the Program<\/code> class.<\/p>\nEmployeeContext<\/code> class (The same data you inserted into a real SQL Server database at the beginning of this series).<\/p>\nIntegration Testing of the Index Action<\/span><\/h2>\n
TestingWebAppFactory<\/code> class:<\/p>\npublic class EmployeesControllerIntegrationTests : IClassFixture<TestingWebAppFactory<Program>>\r\n{\r\n private readonly HttpClient _client;\r\n\r\n public EmployeesControllerIntegrationTests(TestingWebAppFactory<Program> factory) \r\n => _client = factory.CreateClient();\r\n}<\/pre>\nTestingWebAppFactory<\/code> class with the IClassFixture<\/code> interface and inject it in a constructor, where we create an instance of the HttpClient<\/code>. The IClassFixture<\/code> interface is a decorator, which indicates that tests in this class rely on a fixture to run. We can see that the fixture is our TestingWebAppFactory<\/code> class.<\/p>\n[Fact]\r\npublic async Task Index_WhenCalled_ReturnsApplicationForm()\r\n{\r\n var response = await _client.GetAsync(\"\/Employees\");\r\n\r\n response.EnsureSuccessStatusCode();\r\n\r\n var responseString = await response.Content.ReadAsStringAsync();\r\n\r\n Assert.Contains(\"Mark\", responseString);\r\n Assert.Contains(\"Evelin\", responseString);\r\n}<\/pre>\nGetAsync<\/code> method to call the action on the \/Employees<\/code> route, which is the Index<\/code> action, and return a result in a response<\/code> variable. With the EnsureSuccessStatusCode<\/code> method, we verify that the IsSuccessStatusCode<\/code> property is set to true.<\/p>\nReadAsStringAsync<\/code> method and verify that it contains our two employees.<\/p>\nSystem.InvalidOperationException : Relational-specific methods can only be used when the context is using a relational database provider.<\/code><\/p>\nMigrationManager<\/code> class can execute migrations only with the real SQL server and not with the in-memory one. So to fix this issue, we are going to modify the try block in that class:<\/p>\ntry\r\n{\r\n if (appContext.Database.ProviderName != \"Microsoft.EntityFrameworkCore.InMemory\")\r\n appContext.Database.Migrate();\r\n}<\/pre>\n![\"Integration](\"https:\/\/code-maze.com\/wp-content\/uploads\/2021\/11\/10-Integration-tests-of-the-Index-action-in-ASP.NET-Core.png\")
<\/a><\/p>\nCreate<\/code> actions.<\/p>\nIntegration Testing of the Create (GET) Action in ASP.NET Core<\/span><\/h2>\n
Create.cshtml<\/code> file, from the Views\\Employees<\/code> folder, and modify it by changing the h4<\/code> tag (just to have more than one word to test):<\/p>\n<h4>Please provide a new employee data<\/h4><\/pre>\n
[Fact]\r\npublic async Task Create_WhenCalled_ReturnsCreateForm()\r\n{\r\n var response = await _client.GetAsync(\"\/Employees\/Create\");\r\n\r\n response.EnsureSuccessStatusCode();\r\n\r\n var responseString = await response.Content.ReadAsStringAsync();\r\n\r\n Assert.Contains(\"Please provide a new employee data\", responseString);\r\n}<\/pre>\n![\"Integration](\"https:\/\/code-maze.com\/wp-content\/uploads\/2021\/11\/11-Integration-testing-of-the-Create-GET-Action-to-return-a-create-form.png\")
<\/a><\/p>\nTesting the Create (POST) Action<\/span><\/h2>\n
Create<\/code> page, is invalid. And yes, in a previous article<\/a>, we had test methods for the invalid model, but without an HTTP request.<\/p>\n[Fact]\r\npublic async Task Create_SentWrongModel_ReturnsViewWithErrorMessages()\r\n{\r\n var postRequest = new HttpRequestMessage(HttpMethod.Post, \"\/Employees\/Create\");\r\n\r\n var formModel = new Dictionary<string, string>\r\n {\r\n { \"Name\", \"New Employee\" },\r\n { \"Age\", \"25\" }\r\n };\r\n\r\n postRequest.Content = new FormUrlEncodedContent(formModel);\r\n \r\n var response = await _client.SendAsync(postRequest);\r\n \r\n response.EnsureSuccessStatusCode();\r\n \r\n var responseString = await response.Content.ReadAsStringAsync();\r\n \r\n Assert.Contains(\"Account number is required\", responseString);\r\n}<\/pre>\nformModel<\/code> object as a dictionary, which consists of the elements that we have on the Create page. Of course, we didn\u2019t provide all the elements, the AccountNumber<\/code> is missing because we want to send invalid data.<\/p>\nformModel<\/code> as a content in our request, send that request with the SendAsync<\/code> method and ensure that the response is successful.<\/p>\nEmployee<\/code> model class, we are going to see that if the AccountNumber<\/code> is not provided, the error message should appear on the form:<\/p>\n[Required(ErrorMessage = \"Account number is required\")] \r\npublic string AccountNumber { get; set; }<\/pre>\n![\"Integration](\"https:\/\/code-maze.com\/wp-content\/uploads\/2021\/11\/12-Integration-testing-of-the-Create-POST-Action-that-fails.png\")
<\/a><\/p>\nThe ValidateAntiForgeryToken Attribute Causing Integration Test to Fail<\/h3>\n