Missing example on how to use TestServer with ASP.NET 6

[benm-eras]

The section titled Test with WebApplicationFactory or TestServer only includes an example of how to use the WebApplicationFactory with .NET 6. Is the TestServer still available in .NET 6? If so, is it possible to use it with Blazor?

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• ID: 20acee3e-8b6e-b3fb-8271-661e1a287bdd
• Version Independent ID: 20acee3e-8b6e-b3fb-8271-661e1a287bdd
• Content: Code samples migrated to the new minimal hosting model in 6.0
• Content Source: aspnetcore/migration/50-to-60-samples.md
• Product: aspnet-core
• Technology: aspnetcore-migration
• GitHub Login: @Rick-Anderson
• Microsoft Alias: riande

[guardrex]

@benm-eras ... The Blazor (Razor component) test guidance is located in the Blazor node at ...

https://docs.microsoft.com/aspnet/core/blazor/test

AFAICT, there has been work on TestServer for Blazor testing scenarios since that topic went up. The testing guidance was put up ~18 months ago. This is a good time to ask if it's all still valid and good in it's present form or if it will need work. I'll ping Artak offline to see where things stand.

[benm-eras]

Thanks @guardrex I was looking into starting the app to run integration tests on it with Playwright. I have done this in .NET 5 with Microsoft.Extensions.Hosting.Host.CreateDefaultBuilder() as per the .NET 5 instructions on using TestServer, and it still seems to work with .NET 6, it just struck me as odd that it wasn't in the Docs.

[guardrex]

Yes, I'm trying to jog my memory on this subject after 18 months. No issues on this subject have been opened since then IIRC.

Now that you mention it, yes ... I just looked 👀 ... I see/recall now that Playwright is just for the browser automation aspect.

TestServer has had work when problems were reported to the product unit. I see the issues/PRs in their repo.

an example of how to use the WebApplicationFactory with .NET 6

There's a line at the end tho that says ...

The .NET 5 version and .NET 6 version with the WebApplicationFactory are identical by design.

... referring to ...

https://docs.microsoft.com/en-us/aspnet/core/migration/50-to-60-samples?view=aspnetcore-6.0#aspnet-core-6-9

Does that cover your ask here?

[benm-eras]

I am looking to use the "TestServer" method and the resulting IHost, not so much the WebApplicationFactory which will give you an HttpClient. This is because I need to have the application available at a given URL/Port to point Playwright at.

I see no mention of TestServer or creating an IHost in the .NET 6 section of the page. As I say my existing .NET 5 code seems to work:

var host = Microsoft.Extensions.Hosting.Host
    .CreateDefaultBuilder()
    .UseEnvironment(this.Environment)
    .ConfigureAppConfiguration(b => {  /* do app config */ })
    .ConfigureWebHostDefaults(b=> b.UseUrls(myUrl).UseStartup<MyStartup>())
    .ConfigureServices((b,s) => { /* add stuff to DI container */ })
    .Build();

await host.StartAsync();

I can then point Playwright (or my browser) to myUrl and I am good to go. So if you tell me that the .NET 6 version of this is identical to .NET 5 I will be a happy camper, though I feel that last sentence needs amending to explicitly mention TestServer/IHost?

[guardrex]

I see. They did place a Q&A here ...

https://docs.microsoft.com/en-us/aspnet/core/migration/50-to-60?view=aspnetcore-6.0&tabs=visual-studio#faq

Scroll down to ...

• Do WebApplicationFactory and TestServer still work?

  Yes. WebApplicationFactory<TEntryPoint> is the way to test the new hosting model. For an example, see Test with WebApplicationFactory or TestServer.

Rick, I'm going to leave this up to you if you want to make further updates. I thought for a moment that this was more directly Blazor-related, but the team is still recommending our Blazor guidance for the component testing aspects. This issue is about TestServer migration coverage, so it's not really in my wheelhouse.

[benm-eras]

Ah I see, I still don't think that is very clear as I don't think I would be able to use the WebApplicationFactory<TEntryPoint> to do integration testing with Playwright (or similar) unless I am missing something? Where they link to "[Test with WebApplicationFactory or TestServer]"(https://docs.microsoft.com/en-us/aspnet/core/migration/50-to-60-samples?view=aspnetcore-6.0#twa) there is no advice on TestServer for .NET 6.

Everything is working as I would expect, but I just think the Docs need some more information on .NET 6 and TestServer. Thanks for your time regardless.

[guardrex]

Yeah ... Rick will be along in a bit to see if a line (and/or example) makes sense.

What I'm going to do is make a note on a tracking issue that I use for Blazor docs to provide guidance about the TestServer setup for Playwright (probably including the non-TestServer Blazor WASM case) or cross-link to anything helpful on it in Playwright docs (although I doubt that they say anything really about this aspect). We might end up having full working examples in the Blazor topic, regardless of what's done with the migration coverage.

[benm-eras]

Brilliant, thanks Luke

[Rick-Anderson]

This will be covered in #27089