React to WebHostBuilderFactory changes

[Tratcher]

#6460, #5960 The shared sources packages was moved to Extensions and refactored to support the new generic host templates pattern. This change:

• Removes the old shared sources package
• Updates TestHost
• Updates MVC's WebApplicationFactory

Note to make WebApplicationFactory work I needed to skip calling two protected methods: CreateWebHostBuilder and CreateTestServer. Also, ConfigureTestServices isn't needed anymore since there's only one container.

[davidfowl]

Hacky, I like it 😄

[javiercn]

Overall the PR looks good, but there are some changes we need to address before we move forward to ensure backwards compat and that the same user experience is preserved.

[natemcmaster]

A few minor project-file things.

Resolved

[Tratcher]

@javiercn I added a protected method for CreateHostBuilder. CreateTestServer wasn't salvageable. I tried changing it to void Build() as discussed but that broke the DelegatedWebApplicationFactory model.

[Tratcher]

@javiercn I suggest we merge this for preview2 and follow up on further improvements. Ack?

[javiercn]

@Tratcher let me take a look first

[javiercn]

CreateTestServer wasn't salvageable. I tried changing it to void Build() as discussed but that broke the DelegatedWebApplicationFactory model.

@Tratcher I imagine that's because of the side effect of assigning the host. Is that the case?

@javiercn I suggest we merge this for preview2 and follow up on further improvements. Ack?

How much of the DelegatedWebApplicationFactoryModel broke? Everything, or only the CreateServer part?

You could fix the Build() part by passing the WAF as a parameter and adding a protected method to set it that check is null or throws before setting it. That way if someone customizes it, we can still call their implementation and they can set it in a safe way.

public virtual void CreateServer(WebApplicationFactory<TEntryPoint>waf, IHostBuilder builder)

On our implementation

CreateServer(this, builder);

On a derived implementation

...something,
waf.SetInitializedHost(host);
...

or

...something,
base.CreateServer(this,builder);
...something
...

Another alternative is to break it into two

public virtual IHost CreateHost(IHostBuilder builder)

and IServer {get;} be a shortcut for _host.Services.GetRequiredService();

We can clean it up after preview2, but I rather keep this working.

[javiercn]

Overall looks good, just the feedback about CreateServer. If we change it to CreateHost(hostBuilder) and get rid of _server so that we can preserve the delegation model, we should be fine.

[natemcmaster]

Approving from a project file/targets perspective only. I'll let others review the c# changes more carefully.

[Tratcher]

Hmm, what if I split CreateServer like I did for CreateWebHostBuilder? E.g. I add a new IHost CreateHost(IHostBuilder) that's called for the generic host code path and you keep TestServer CreateServer(IWebHostBuilder) for the web host code path.

[Tratcher]

Updated. CreateHost got everything working.

[javiercn]

Looks great!

[BlacKCaT27]

Question: are there plans to update the documentation for this here (https://docs.microsoft.com/en-us/aspnet/core/test/integration-tests?view=aspnetcore-3.0)? Or is the change supposed to be backwards compatible such that there shouldn't be any changes to the docs?

I'm on the latest preview build of .net core 3.0 and while converting our app from 2.2 to 3.0, all of our component tests which rely on WebApplicationFactory are now failing. It appears they're not honoring the mock services we try to inject into the TestServer before creating the client.

Setup:

        public void Init()
        {
            _factory = new WebApplicationFactory<Startup>();
        
        }

Usage in failed test:

            var mockCacheService = new Mock<ICacheService>();
            mockScheduleClient
                .Setup()
                .ReturnsAsync(page);
            using var client = _factory.WithWebHostBuilder(builder =>
                 {
                     builder.ConfigureTestServices(services =>
                     {
                         services.AddScoped(serviceProvider => mockScheduleClient.Object);
                         services.AddSingleton(mockCacheService.Object);
                     });
                 })
                .CreateClient();

Results in:

    System.AggregateException : Some services are not able to be constructed (Error while validating the service descriptor 'ServiceType: #####.ICacheService Lifetime: Scoped ImplementationType: #####.RedisCacheService': Unable to resolve service for type '#####.IJsonConverter' while attempting to activate '#####.RedisCacheService'.)
      ----> System.InvalidOperationException : Error while validating the service descriptor 'ServiceType: #####.ICacheService Lifetime: Scoped ImplementationType: #####.RedisCacheService': Unable to resolve service for type '#####.IJsonConverter' while attempting to activate '#####.RedisCacheService'.
      ----> System.InvalidOperationException : Unable to resolve service for type '#####.IJsonConverter' while attempting to activate '#####.RedisCacheService'.
  Stack Trace: 
    at ServiceProvider.ctor(IEnumerable`1 serviceDescriptors, ServiceProviderOptions options)
    at ServiceCollectionContainerBuilderExtensions.BuildServiceProvider(IServiceCollection services, ServiceProviderOptions options)
    at DefaultServiceProviderFactory.CreateServiceProvider(IServiceCollection containerBuilder)
    at ServiceFactoryAdapter`1.CreateServiceProvider(Object containerBuilder)
    at HostBuilder.CreateServiceProvider()
    at HostBuilder.Build()
    at WebApplicationFactory`1.CreateHost(IHostBuilder builder)
    at DelegatedWebApplicationFactory.CreateHost(IHostBuilder builder)
    at WebApplicationFactory`1.EnsureServer()
    at WebApplicationFactory`1.CreateDefaultClient(DelegatingHandler[] handlers)
    at WebApplicationFactory`1.CreateDefaultClient(Uri baseAddress, DelegatingHandler[] handlers)
    at WebApplicationFactory`1.CreateClient(WebApplicationFactoryClientOptions options)
    at WebApplicationFactory`1.CreateClient()

(##### replaces company-specific non-relevant namespace names).

Please let me know if I should open a new issue but this seems directly related to the refactoring done on this ticket.

[javiercn]

@BlacKCaT27 Hi,

thanks for contacting us. Could you file a new issue with your problem so that we can track this separately?

We most likely will have to update the documentation for this.