GraphServiceClient lifetime

[albus-sonitus]

I've been struggling a bit with whether or not I should be registering a GraphServiceClient with a singleton or scoped lifetime. I see in the AddMicrosoftGraph extension method that it's been added with a scoped lifetime. Is there a reason for this? I've seen recommendations that one should keep the client around and creating new clients all the time isn't a good idea. Originally, I was hesitant to make it a singleton due to token expirations, but after further digging, it looks like the client is fetching a new token on every request. (I could be wrong there. I've been digging through the code and not entirely confident I was looking in the right place.) Any insights? As a very basic example, I was hoping to something like..

services.AddSingleton(new GraphServiceClient(new ManagedIdentityCredential()));

My worry is that the token will expire at some point during the lifetime of the application, unless it will automatically refresh? If it's fetching a new one for every request, then I guess it's a moot point. Where am I going wrong here?