[Feature Request] Support dynamic worker registration at runtime

[oatiz]

Summary

I'd like to request support for dynamically registering workers at runtime, rather than only at application startup.

Use Case

In my application, I need to add workers dynamically based on runtime conditions, such as:

• User-defined task types loaded from a database/configuration
• Adding new job handlers without restarting the application

Current Behavior

Currently, workers must be registered before calling Monitor::run():

Monitor::::new()
    .register(worker1)
    .register(worker2)
    .run()
    .await

Once run() is called, there's no way to add additional workers.

Questions

1. Is this use case something you've considered?
2. Are there architectural constraints that make this difficult to implement?
3. Is there a workaround I might be missing?

Thank you for this excellent library! 🙏

[geofmureithi]

1. Is this something we have considered?
   Not really, Monitor::run consumes in self because we need full ownership of the worker futures to poll them. On first view this change would be mainly hard to achieve with the current API because of this.
2. Are there architectural constraints that make this difficult to implement?
   See answer 1
3. Is there a workaround I might be missing?
   If you don't need to use Monitor, then your problem becomes easy because a Worker can be represented as a future, meaning you can create it dynamically and await it anywhere in the code. You would lose some functionality like a global shutdown and a global event emit system but workers have a way of setting these. The feature that might be tricky is restarting a worker, but here you can just drop the previous dead worker and start a new one.

User-defined task types loaded from a database/configuration

You can still do this but you would need to load the config first before calling run

That said, I think this is an interesting feature and will consider it in the future.

I am happy you find this library helpful! Be sure to give it a star if you have not.

[geofmureithi]

I will be converting this to a discussion as I dont think there is expected much traction on this before v1 is out.