2.5 Test the host

using System.Net;
using System.Net.Http.Json;
using Microsoft.AspNetCore.Mvc.Testing;
using Shopfront.Trains.PlaceOrder;
 
namespace Shopfront.Tests.IntegrationTests;
 
[TestFixture]
public class HostTests
{
    private WebApplicationFactory<Program> _app = null!;
 
    [SetUp]
    public void StartTheApplication() => _app = new WebApplicationFactory<Program>();
 
    [TearDown]
    public ValueTask StopTheApplication() => _app.DisposeAsync();
 
    [Test]
    public async Task PostOrders_InStock_Answers200WithTheOrder()
    {
        var response = await _app.CreateClient()
            .PostAsJsonAsync(
                "/orders",
                new { customerId = "ada", lines = new[] { new { sku = "MUG", quantity = 2 } } }
            );
 
        response.StatusCode.Should().Be(HttpStatusCode.OK);
        var order = await response.Content.ReadFromJsonAsync<PlaceOrderOutput>();
        order!.Total.Should().Be(24.00m);
    }
 
    [Test]
    public async Task PostOrders_OutOfStock_Answers422WithTheReason()
    {
        var response = await _app.CreateClient()
            .PostAsJsonAsync(
                "/orders",
                new { customerId = "ada", lines = new[] { new { sku = "CAP", quantity = 1 } } }
            );
 
        response.StatusCode.Should().Be(HttpStatusCode.UnprocessableEntity);
        (await response.Content.ReadFromJsonAsync<string>()).Should().Be("CAP is out of stock.");
    }
}