daohualiuxiang
/
AspNetCore.Docs
mirror of https://github.com/dotnet/AspNetCore.Docs.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
AspNetCore.Docs/aspnetcore/test/integration-tests.md

29 KiB
Raw Blame History

title author description monikerRange ms.author ms.custom ms.date uid
Integration tests in ASP.NET Core tdykstra Learn how integration tests ensure that an app's components function correctly at the infrastructure level, including the database, file system, and network. >= aspnetcore-3.1 tdykstra mvc 2/29/2024 test/integration-tests

Integration tests in ASP.NET Core

By Jos van der Til, Martin Costello, and Javier Calvarro Nelson.

Integration tests ensure that an app's components function correctly at a level that includes the app's supporting infrastructure, such as the database, file system, and network. ASP.NET Core supports integration tests using a unit test framework with a test web host and an in-memory test server.

:::moniker range=">= aspnetcore-8.0"

This article assumes a basic understanding of unit tests. If unfamiliar with test concepts, see the Unit Testing in .NET Core and .NET Standard article and its linked content.

View or download sample code (how to download)

The sample app is a Razor Pages app and assumes a basic understanding of Razor Pages. If you're unfamiliar with Razor Pages, see the following articles:

For testing SPAs, we recommend a tool such as Playwright for .NET, which can automate a browser.

[!INCLUDE]

There's virtually no difference between the configuration for tests of Razor Pages apps and MVC apps. The only difference is in how the tests are named. In a Razor Pages app, tests of page endpoints are usually named after the page model class (for example, IndexPageTests to test component integration for the Index page). In an MVC app, tests are usually organized by controller classes and named after the controllers they test (for example, HomeControllerTests to test component integration for the Home controller).

Test app prerequisites

The test project must:

These prerequisites can be seen in the sample app. Inspect the tests/RazorPagesProject.Tests/RazorPagesProject.Tests.csproj file. The sample app uses the xUnit test framework and the AngleSharp parser library, so the sample app also references:

In apps that use xunit.runner.visualstudio version 2.4.2 or later, the test project must reference the Microsoft.NET.Test.Sdk package.

Entity Framework Core is also used in the tests. See the project file in GitHub.

SUT environment

If the SUT's environment isn't set, the environment defaults to Development.

Basic tests with the default WebApplicationFactory

Expose the implicitly defined Program class to the test project by doing one of the following:

  • Expose internal types from the web app to the test project. This can be done in the SUT project's file (.csproj):

    <ItemGroup>
     <InternalsVisibleTo Include="MyTestProject" />
</ItemGroup>

  • Make the Program class public using a partial class declaration:

    var builder = WebApplication.CreateBuilder(args);
// ... Configure services, routes, etc.
app.Run();
+ public partial class Program { }

    The sample app uses the Program partial class approach.

xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory%601 is used to create a xref:Microsoft.AspNetCore.TestHost.TestServer for the integration tests. TEntryPoint is the entry point class of the SUT, usually Program.cs.

Test classes implement a class fixture interface (IClassFixture) to indicate the class contains tests and provide shared object instances across the tests in the class.

The following test class, BasicTests, uses the WebApplicationFactory to bootstrap the SUT and provide an xref:System.Net.Http.HttpClient to a test method, Get_EndpointsReturnSuccessAndCorrectContentType. The method verifies the response status code is successful (200-299) and the Content-Type header is text/html; charset=utf-8 for several app pages.

xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory%601.CreateClient creates an instance of HttpClient that automatically follows redirects and handles cookies.

[!code-csharp]

By default, non-essential cookies aren't preserved across requests when the General Data Protection Regulation consent policy is enabled. To preserve non-essential cookies, such as those used by the TempData provider, mark them as essential in your tests. For instructions on marking a cookie as essential, see Essential cookies.

AngleSharp vs Application Parts for antiforgery checks

This article uses the AngleSharp parser to handle the antiforgery checks by loading pages and parsing the HTML. For testing the endpoints of controller and Razor Pages views at a lower-level, without caring about how they render in the browser, consider using Application Parts. The Application Parts approach injects a controller or Razor Page into the app that can be used to make JSON requests to get the required values. For more information, see the blog Integration Testing ASP.NET Core Resources Protected with Antiforgery Using Application Parts and associated GitHub repo by Martin Costello.

Customize WebApplicationFactory

Web host configuration can be created independently of the test classes by inheriting from xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory%601 to create one or more custom factories:

  1. Inherit from WebApplicationFactory and override xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory%601.ConfigureWebHost%2A. The xref:Microsoft.AspNetCore.Hosting.IWebHostBuilder allows the configuration of the service collection with IWebHostBuilder.ConfigureServices

    [!code-csharp]

    Database seeding in the sample app is performed by the InitializeDbForTests method. The method is described in the Integration tests sample: Test app organization section.

    The SUT's database context is registered in Program.cs. The test app's builder.ConfigureServices callback is executed after the app's Program.cs code is executed. To use a different database for the tests than the app's database, the app's database context must be replaced in builder.ConfigureServices.

    The sample app finds the service descriptor for the database context and uses the descriptor to remove the service registration. The factory then adds a new ApplicationDbContext that uses an in-memory database for the tests..

    To connect to a different database, change the DbConnection. To use a SQL Server test database:

  1. Use the custom CustomWebApplicationFactory in test classes. The following example uses the factory in the IndexPageTests class:

    [!code-csharp]

    The sample app's client is configured to prevent the HttpClient from following redirects. As explained later in the Mock authentication section, this permits tests to check the result of the app's first response. The first response is a redirect in many of these tests with a Location header.

  2. A typical test uses the HttpClient and helper methods to process the request and the response:

    [!code-csharp]

Any POST request to the SUT must satisfy the antiforgery check that's automatically made by the app's data protection antiforgery system. In order to arrange for a test's POST request, the test app must:

  1. Make a request for the page.
  2. Parse the antiforgery cookie and request validation token from the response.
  3. Make the POST request with the antiforgery cookie and request validation token in place.

The SendAsync helper extension methods (Helpers/HttpClientExtensions.cs) and the GetDocumentAsync helper method (Helpers/HtmlHelpers.cs) in the sample app use the AngleSharp parser to handle the antiforgery check with the following methods:

AngleSharp is a third-party parsing library used for demonstration purposes in this article and the sample app. AngleSharp isn't supported or required for integration testing of ASP.NET Core apps. Other parsers can be used, such as the Html Agility Pack (HAP). Another approach is to write code to handle the antiforgery system's request verification token and antiforgery cookie directly. See AngleSharp vs Application Parts for antiforgery checks in this article for more information.

The EF-Core in-memory database provider can be used for limited and basic testing, however the SQLite provider is the recommended choice for in-memory testing.

See Extend Startup with startup filters which shows how to configure middleware using xref:Microsoft.AspNetCore.Hosting.IStartupFilter, which is useful when a test requires a custom service or middleware.

Customize the client with WithWebHostBuilder

When additional configuration is required within a test method, xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory%601.WithWebHostBuilder%2A creates a new WebApplicationFactory with an xref:Microsoft.AspNetCore.Hosting.IWebHostBuilder that is further customized by configuration.

The sample code calls WithWebHostBuilder to replace configured services with test stubs. For more information and example usage, see Inject mock services in this article.

The Post_DeleteMessageHandler_ReturnsRedirectToRoot test method of the sample app demonstrates the use of WithWebHostBuilder. This test performs a record delete in the database by triggering a form submission in the SUT.

Because another test in the IndexPageTests class performs an operation that deletes all of the records in the database and may run before the Post_DeleteMessageHandler_ReturnsRedirectToRoot method, the database is reseeded in this test method to ensure that a record is present for the SUT to delete. Selecting the first delete button of the messages form in the SUT is simulated in the request to the SUT:

[!code-csharp]

Client options

See the xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactoryClientOptions page for defaults and available options when creating HttpClient instances.

Create the WebApplicationFactoryClientOptions class and pass it to the xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory%601.CreateClient method:

[!code-csharp]

NOTE: To avoid HTTPS redirection warnings in logs when using HTTPS Redirection Middleware, set BaseAddress = new Uri("https://localhost")

Inject mock services

Services can be overridden in a test with a call to xref:Microsoft.AspNetCore.TestHost.WebHostBuilderExtensions.ConfigureTestServices%2A on the host builder. To scope the overridden services to the test itself, the xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory%601.WithWebHostBuilder%2A method is used to retrieve a host builder. This can be seen in the following tests:

The sample SUT includes a scoped service that returns a quote. The quote is embedded in a hidden field on the Index page when the Index page is requested.

Services/IQuoteService.cs:

[!code-csharp]

Services/QuoteService.cs:

[!code-csharp]

Program.cs:

[!code-csharp]

Pages/Index.cshtml.cs:

[!code-csharp]

Pages/Index.cs:

[!code-cshtml]

The following markup is generated when the SUT app is run:

<input id="quote" type="hidden" value="Come on, Sarah. We&#x27;ve an appointment in 
    London, and we&#x27;re already 30,000 years late.">

To test the service and quote injection in an integration test, a mock service is injected into the SUT by the test. The mock service replaces the app's QuoteService with a service provided by the test app, called TestQuoteService:

IntegrationTests.IndexPageTests.cs:

[!code-csharp]

ConfigureTestServices is called, and the scoped service is registered:

[!code-csharp]

The markup produced during the test's execution reflects the quote text supplied by TestQuoteService, thus the assertion passes:

<input id="quote" type="hidden" value="Something&#x27;s interfering with time, 
    Mr. Scarman, and time is my business.">

Mock authentication

Tests in the AuthTests class check that a secure endpoint:

  • Redirects an unauthenticated user to the app's sign in page.
  • Returns content for an authenticated user.

In the SUT, the /SecurePage page uses an xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.AuthorizePage%2A convention to apply an xref:Microsoft.AspNetCore.Mvc.Authorization.AuthorizeFilter to the page. For more information, see Razor Pages authorization conventions.

[!code-csharp]

In the Get_SecurePageRedirectsAnUnauthenticatedUser test, a xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactoryClientOptions is set to disallow redirects by setting xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactoryClientOptions.AllowAutoRedirect to false:

[!code-csharp]

By disallowing the client to follow the redirect, the following checks can be made:

The test app can mock an xref:Microsoft.AspNetCore.Authentication.AuthenticationHandler%601 in xref:Microsoft.AspNetCore.TestHost.WebHostBuilderExtensions.ConfigureTestServices%2A in order to test aspects of authentication and authorization. A minimal scenario returns an xref:Microsoft.AspNetCore.Authentication.AuthenticateResult.Success%2A?displayProperty=nameWithType:

[!code-csharp]

The TestAuthHandler is called to authenticate a user when the authentication scheme is set to TestScheme where AddAuthentication is registered for ConfigureTestServices. It's important for the TestScheme scheme to match the scheme your app expects. Otherwise, authentication won't work.

[!code-csharp]

For more information on WebApplicationFactoryClientOptions, see the Client options section.

Basic tests for authentication middleware

See this GitHub repository for basic tests of authentication middleware. It contains a test server that’s specific to the test scenario.

Set the environment

Set the environment in the custom application factory:

[!code-csharp]

How the test infrastructure infers the app content root path

The WebApplicationFactory constructor infers the app content root path by searching for a xref:Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactoryContentRootAttribute on the assembly containing the integration tests with a key equal to the TEntryPoint assembly System.Reflection.Assembly.FullName. In case an attribute with the correct key isn't found, WebApplicationFactory falls back to searching for a solution file (.sln) and appends the TEntryPoint assembly name to the solution directory. The app root directory (the content root path) is used to discover views and content files.

Disable shadow copying

Shadow copying causes the tests to execute in a different directory than the output directory. If your tests rely on loading files relative to Assembly.Location and you encounter issues, you might have to disable shadow copying.

To disable shadow copying when using xUnit, create a xunit.runner.json file in your test project directory, with the correct configuration setting:

{
  "shadowCopy": false
}

Disposal of objects

After the tests of the IClassFixture implementation are executed, xref:Microsoft.AspNetCore.TestHost.TestServer and xref:System.Net.Http.HttpClient are disposed when xUnit disposes of the WebApplicationFactory. If objects instantiated by the developer require disposal, dispose of them in the IClassFixture implementation. For more information, see Implementing a Dispose method.

Integration tests sample

The sample app is composed of two apps:

App Project directory Description
Message app (the SUT) src/RazorPagesProject Allows a user to add, delete one, delete all, and analyze messages.
Test app tests/RazorPagesProject.Tests Used to integration test the SUT.

The tests can be run using the built-in test features of an IDE, such as Visual Studio. If using Visual Studio Code or the command line, execute the following command at a command prompt in the tests/RazorPagesProject.Tests directory:

dotnet test

Message app (SUT) organization

The SUT is a Razor Pages message system with the following characteristics:

  • The Index page of the app (Pages/Index.cshtml and Pages/Index.cshtml.cs) provides a UI and page model methods to control the addition, deletion, and analysis of messages (average words per message).
  • A message is described by the Message class (Data/Message.cs) with two properties: Id (key) and Text (message). The Text property is required and limited to 200 characters.
  • Messages are stored using Entity Framework's in-memory database†.
  • The app contains a data access layer (DAL) in its database context class, AppDbContext (Data/AppDbContext.cs).
  • If the database is empty on app startup, the message store is initialized with three messages.
  • The app includes a /SecurePage that can only be accessed by an authenticated user.

†The EF article, Test with InMemory, explains how to use an in-memory database for tests with MSTest. This topic uses the xUnit test framework. Test concepts and test implementations across different test frameworks are similar but not identical.

Although the app doesn't use the repository pattern and isn't an effective example of the Unit of Work (UoW) pattern, Razor Pages supports these patterns of development. For more information, see Designing the infrastructure persistence layer and Test controller logic (the sample implements the repository pattern).

Test app organization

The test app is a console app inside the tests/RazorPagesProject.Tests directory.

Test app directory Description
AuthTests Contains test methods for:
BasicTests Contains a test method for routing and content type.
IntegrationTests Contains the integration tests for the Index page using custom WebApplicationFactory class.
Helpers/Utilities
  • Utilities.cs contains the InitializeDbForTests method used to seed the database with test data.
  • HtmlHelpers.cs provides a method to return an AngleSharp IHtmlDocument for use by the test methods.
  • HttpClientExtensions.cs provide overloads for SendAsync to submit requests to the SUT.

The test framework is xUnit. Integration tests are conducted using the xref:Microsoft.AspNetCore.TestHost?displayProperty=fullNames, which includes the xref:Microsoft.AspNetCore.TestHost.TestServer. Because the Microsoft.AspNetCore.Mvc.Testing package is used to configure the test host and test server, the TestHost and TestServer packages don't require direct package references in the test app's project file or developer configuration in the test app.

Integration tests usually require a small dataset in the database prior to the test execution. For example, a delete test calls for a database record deletion, so the database must have at least one record for the delete request to succeed.

The sample app seeds the database with three messages in Utilities.cs that tests can use when they execute:

[!code-csharp]

The SUT's database context is registered in Program.cs. The test app's builder.ConfigureServices callback is executed after the app's Program.cs code is executed. To use a different database for the tests, the app's database context must be replaced in builder.ConfigureServices. For more information, see the Customize WebApplicationFactory section.

Additional resources

:::moniker-end

[!INCLUDE] [!INCLUDE]