Testcontainers guides

Testcontainers and WebApplicationFactory Guide

The following explains how to integrate a testcontainer instance with ASP.NET Core integration tests built on WebApplicationFactory<TEntryPoint>.

WebApplicationFactory with a built-in Testcontainer

public class SpecificApplicationFactory : WebApplicationFactory<Program>, IAsyncLifetime
{
    private TestContainer _testContainer;

    public SpecificApplicationFactory()
    {
        _testContainer = new TestContainer("testcontainer")
            .Build();
    }

    public Task InitializeAsync()
    {
        return _testContainer.StartAsync();
    }

    public new async Task DisposeAsync()
    {
        await _testContainer.StopAsync();
        await _testContainer.DisposeAsync();
    }

    protected override void ConfigureWebHost(IWebHostBuilder builder)
    {
        builder.ConfigureAppConfiguration(config =>
        {
            KeyValuePair<string, string>[] collection =
            [
                new KeyValuePair<string, string>(
                    key: $"ConnectionStrings:TestContainer",
                    value: _testContainer.GetConnectionString())
            ];

            return configurationBuilder.AddInMemoryCollection(collection!);
        });
    }
}

public class ExampleTests : IClassFixture<SpecificApplicationFactory>
{
    private readonly HttpClient _client;

    public ExampleTests(SpecificApplicationFactory factory)
    {
        _client = factory.CreateClient();
    }

    [Fact]
    public async Task Get_ReturnsSuccess()
    {
        var response = await _client.GetAsync("/api/values");
        response.EnsureSuccessStatusCode();
    }
}