Hosting a test application for automated integration tests.

AspNetCoreIntegrationTest.cs

[Theory]
[InlineData("Development")]
public async Task CallSwaggerEndpoint_ShouldReturnHttpOk(string environment)
{
    // Arrange
    using var sut = await Program.CreateHostBuilder(null)
        .UseEnvironment(environment)
        .UseDefaultServiceProvider((context, options) =>
        {
            options.ValidateScopes = true;
            options.ValidateOnBuild = true;
        })
        .ConfigureWebHost(webBuilder =>
        {
            webBuilder.UseTestServer();
        })
        .StartAsync();

    var client = sut.GetTestServer().CreateClient();

    // Act
    var response = await client.GetAsync($"/swagger/v1/swagger.json");

    // Assert
    response.StatusCode.Should().Be(HttpStatusCode.OK);
}