ServerBuilder is never dropped

[jwiesler]

Hi,

I noticed that ServerBuilder is not dropped after the server is stopped. It doesn't matter whether ServerBuilder::exit is true and System::current().stop() is called (it really should happen then shouldn't it?) or not. Furthermore, the ServerBuilder future can never complete because it returns Pending even when the command receiver returns None!

Is this intended? I'm relying on web::Data<T> being dropped after the server shuts down, but ServerBuilder holds the last reference to it forever.

[jwiesler]

ServerBuilder is dropped after main exits. This leaves two questions:

• If ServerBuilder runs on the same System as main, what does System::stop even do? I can await futures in main even after stop was called.
• How do I fix this? How can I run more cleanup code after ServerBuilder dropped? Would running the actix sytem for the server from a tokio main method help?

[fakeshadow]

https://github.com/actix/actix-net/blob/1c8fcaebbc2f385acece09f7fcc2fd565daae1c4/actix-server/tests/test_server.rs#L19

You need another scope to do anything after runtime shutdown. If you just straight exit main when runtime shutdown you can't do any meaningful work.

That said in general you are encouraged to do all the work inside the actix-runtime context. Design your clean up logic to fit it could be a better solution overall.

[jwiesler]

That said in general you are encouraged to do all the work inside the actix-runtime context.

Are there any examples for this? I need to shut down background workers but I know of no way to react to the server shutting down or even receive a notification that it does so.

And how should I handle shutting down IO? In theory it might take ages to write the last 10 bytes of an operation and stopping the System will interrupt the write process and corrupt the file.