Which part of Session is incompatible with NativeAOT?

[josephmoresena]

While reviewing Native AOT compatibility, I saw that it mentions the Session object is not supported with NativeAOT. I've noticed that the AddSession extension is marked with RequiresUnreferencedCode, but I'm not exactly sure what it handles dynamically.

I've been able to verify that Session does work with Native AOT using the following setup:

builder.Services.AddDistributedMemoryCache();
builder.Services.AddHttpContextAccessor();

builder.Services.AddSession(options =>
{
	options.IdleTimeout = TimeSpan.FromMinutes(30); 
	options.Cookie.IsEssential = true;
});

Is this incorrect? Could it stop working at some point? I’m only storing and retrieving text and bytes in the session object.

[BrennanConroy]

It's very possible it just wasn't updated as part of making ASP.NET Core trimmable/aot friendly.

If you look at the change history we marked a bunch of APIs this way in April 2023. Later that year we did a bunch of trimming/aot work, including DataProtection (which Session uses) in May 2023.

See https://github.com/dotnet/aspnetcore/blob/main/docs/Trimming.md for some information on what we'd need to do if we removed the attribute to make sure it works.