Allow passing base64 pfx content as HTTPS certificate

[Gerhut]

Is there an existing issue for this?

• I have searched the existing issues

Is your feature request related to a problem? Please describe the problem.

I am trying to apply the HTTPS certificate stored in Azure KeyVault with Krestel server using KeyVault Configuration Provider. By KeyVault Configuration Provider, certificates could be retrieved as secrets in base64-pfx format, while Krestel configuration does not support passing the base64 pfx content directly. Now I have to do either:

Suppose I store the certificate in Azure KeyVault with name Krestel--Certificates--Default--Content

// Program.cs

File.WriteAllBytes("https.pfx", Convert.FromBase64String(builder.Configuration["Krestel:Certiticates:Default:Content"]));

{
  "//": "appsettings.json",
  "Krestel": {
    "Certificates": {
      "Default": {
        "Path": "https.pfx"
      }
    }
  }
}

or

// Program.cs

builder.Services.Configure<KestrelServerOptions>(options =>
{
    options.ConfigureHttpsDefaults(httpsOptions =>
    {
        httpsOptions.ServerCertificate = new(Convert.FromBase64String(builder.Configuration["Krestel:Certificates:Default:Content"]));
    });
});

Describe the solution you'd like

It will be great if we can directly support the key like Krestel:Certificates:Default:Content with base64 encoded pfx format. This will make we migrate from http to https with certs in Azure KeyVault more smoothly - no need to change the code and recompile or write some preprocesses to download the cert to local, just add some fields to configuration and all set.

Additional context

No response