Skip to content

Latest commit

 

History

History
104 lines (69 loc) · 5.34 KB

configuring-webhost.md

File metadata and controls

104 lines (69 loc) · 5.34 KB
Raw

Providing test appsettings files to the test server

Summary

This extension allows you to pass configuration files to use during integration tests.

Motivation

I want to be able to do integration tests as defined in introduction to integration tests and I need to be able to control the configuration for the tests.

The main configuration values I want to be able to control are the ones read from the appsettings files.

Requirements

You will have to add the dotnet-sdk-extensions-testing nuget to your test project.

How to use

Start by creating an integration test as shown in introduction to integration tests.

After, configure the appsettings files to be used on the test by using the IWebHostBuilder.AddTestConfiguration extension method.

Let's say that you create a directory in the root of the test project named AppSettings and that inside you have two files:

  • appsettings.json
  • appsettings.Default.json

Given this you can do a test as shown by the DemoTest method below:

public class ConfigurationDemoTests : IClassFixture<WebApplicationFactory<Progam>>
{
    private readonly WebApplicationFactory<Progam> _webApplicationFactory;

    public ConfigurationDemoTests(WebApplicationFactory<Progam> webApplicationFactory)
    {
        _webApplicationFactory = webApplicationFactory;
    }

    [Fact]
    public async Task DemoTest()
    {
        var httpClient = _webApplicationFactory
            .WithWebHostBuilder(builder =>
            {
                builder
                    .AddTestConfiguration("appsettings.json", "appsettings.Default.json")
                    .ConfigureTestServices(services =>
                    {
                        // inject mocks for any other services
                    });
            })
            .CreateClient();

        // do some calls to your app via the httpClient and then some asserts
    }
}

Note that all of the code in the example above is equal to the demos explained on the official docs except for the addition of the .AddTestConfiguration("appsettings.json", "appsettings.Default.json") line.

Also note that the location of where the test appsettings files are can be configured. See below for more information.

Configure the location of the test appsettings files

You can configure the location of where the appsettings files are by using an overload of IWebHostBuilder.AddTestConfiguration extension method as follows:

.AddTestConfiguration(options => options.AppSettingsDir = "AppSettings", "appsettings.json", "appsettings.Default.json")

The value set for TestConfigurationOptions.AppSettingsDir will be used as a relative path to the current directory (directory where the tests will be executed). It defaults to AppSettings.

Make sure you set your test appsetting files to be copied to the output.

How does it work with the appsettings files outside the test project (ie the real ones on the main project)

When using IWebHostBuilder.AddTestConfiguration any existing Microsoft.Extensions.Configuration.JsonJsonConfigurationSource instances are removed from the IServiceCollection which will be used by the WebApplicationFactory when starting the test server.

This means that any appsettings file that would normally be loaded, the actual ones your app uses when running, are not loaded on the tests.

This is done to avoid acidentally loading some configuration values. It has the small downside that you need to load appsettings files that between them have the required configuration values to run the given test scenario instead of relying on the appsettings used by your app and just overwriting the required bits.

Also note that by default the appsettings that are loaded are based on the environment on which the WebHost is running. As an example, by default when debbuging the app the ASPNETCORE_ENVIRONMENT environment variable is set to Development and the appsettings that are loaded are appsettings.json and appsettings.Development.json.

The IWebHostBuilder.AddTestConfiguration extension method does not take the environment into consideration when loading test appsettings. Following the example in the DemoTest, when doing:

.AddTestConfiguration("appsettings.json", "appsettings.Default.json")

Both the appsettings.json and appsettings.Default.json are loaded as configuration sources. You don't need to make sure the app is running with the ASPNETCORE_ENVIRONMENT environment variable set to Default.

Notes

This extension method works for both IWebHostBuilder and IHostBuilder.