After adding a cookie it does NOT become immediately available in the HttpRequest.Cookies collection

[wpqs]

Describe the bug

The Microsoft Docs says in remarks "After you add a cookie by using the HttpResponse.Cookies collection, the cookie is immediately available in the HttpRequest.Cookies collection, even if the response has not been sent to the client". However, I find that a cookie can't be read immediately after setting, though it does appear in the browser's storage inspector and is read successfully after a page reload.

public class MyCookies
{
   public IHttpContextAccessor Accessor { get; private set; }

   public MyCookies(IHttpContextAccessor accessor)
   {
      Accessor = accessor;
   }

   public bool Set(string name, string value)
    {
       var rc = false;
       Accessor.HttpContext.Response.Cookies.Append(name, value);
       if (Accessor.HttpContext.Request.Cookies.TryGetValue(name, out var result) && (result == value))
          rc = true;
      return rc;
   }

   public string Get(string name)
   {
      var rc = "fail";
      if (Accessor.HttpContext.Request.Cookies.TryGetValue(name, out var result)) 
        rc = $"{name}={result}"; 
      return rc;
   }
}

public class IndexModel : PageModel
{
   private readonly IHttpContextAccessor _httpContextAccessor;

   [BindProperty]
   public string Comment { get; set; }
   public IndexModel(IHttpContextAccessor httpContextAccessor)
   {
         _httpContextAccessor = httpContextAccessor;
   }

   public void OnGet()
   {
        var result = true;
        var cookies = new MyCookies(_httpContextAccessor);
        if (cookies.Set(".AspNetCore.Culture", "fr-CH") == false)
           result = false;
        Comment = (result) ? $"Success: {cookies.Get(".AspNetCore.Culture")}" : $"{cookies.Get(".AspNetCore.Culture")}";
   }
}

To Reproduce

Repro Project BugCookieNotSet Created using VS2019 (16.5.5) using template ASP.NET Core Web Application C#, ASP.NET Core 3.1.

Changes:

MyCookies class

• added as shown above

Startup class

• ConfigureServices(IServiceCollection services) - added services.AddHttpContextAccessor();

Index class

• Ctor initialised _httpContextAccessor as shown above

• Index.OnGet() - creates cookies , invokes its Set method as shown above, and uses return value to decide setting of Comment string - "fail", or display "fr-CH"

Build and Start without Debugging

Index page displays 'fail' as cookies.Set() returned false. This shows the cookie is NOT immediately available in the HttpRequest.Cookies collection. However the expected value 'fr'CH' is displayed upon page reload.

Exceptions (if any)

Further technical details

• ASP.NET Core version 3.1
• developed using VS2019 (16.5.5)
  .NET Core SDK (reflecting any global.json):
  Version: 3.1.202
  Commit: 6ea70c8dca

Runtime Environment:
OS Name: Windows
OS Version: 10.0.18362
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\3.1.202\

Host (useful for support):
Version: 3.1.4
Commit: 0c2e69caa6

.NET Core SDKs installed:
2.1.202 [C:\Program Files\dotnet\sdk]
2.1.402 [C:\Program Files\dotnet\sdk]
2.1.403 [C:\Program Files\dotnet\sdk]
2.1.500 [C:\Program Files\dotnet\sdk]
2.1.504 [C:\Program Files\dotnet\sdk]
2.1.509 [C:\Program Files\dotnet\sdk]
2.2.104 [C:\Program Files\dotnet\sdk]
3.0.101 [C:\Program Files\dotnet\sdk]
3.1.202 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
Microsoft.AspNetCore.All 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.18 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.2.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.18 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.2.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 3.0.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 3.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 2.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.8 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.18 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.2.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 3.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 3.1.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 3.0.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 3.1.4 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

[blowdart]

You're looking at documentation for .NET Framework, not .NET Core.

The Core documentation has no such note, and the behaviour is expected,

[wpqs]

I feared that was the case. I was misdirected as selecting .NET Core 3.1 from the Framework docs for HttpRequest.Cookies Property produces a message "The requested page is not available for .NET Core 3.1. You have been redirected to the newest product version this page is available for." Clearly the page is available.

I have now raised a feature request in the hope that .NET Core will implement the same behaviour as Framework in respect of making cookies immediately available in the HttpRequest.Cookies collection - see issue 24529