Not sure if I understand exactly, but here goes anyway …
When you decorate a function with @anvil.server.callable you can optionally specify the name the function is published as. For example :
@anvil.server.callable("dave")
def myfunctioncalledsomethingelse():
...
would be called like this :
anvil.server.call("dave")
So, when your uplink service starts, generate a random name for your function and use that in your decorator. Then make sure the first thing your function does is to call a server function with that name as a parameter which adds that name to a table.
In that table you then have an enumerable list of attached uplink functions.
You can’t tell (as far as I know) when an uplink function goes away, so what I do is wrap all calls to those functions in a try...except block, and delete the table row if it fails.
Is that any help to you?