Improve upgrade process to reduce number of restarts

[ZeeshanM96]

Description:

Right now, in the polkadot-operator, if one changes two configs at the same time that both include a service restart, e.g. binary-urland wasm-runtime-url, the service will restart twice. This takes extra time and is also unnecessary, there is no benefit to restarting in between the two config changes. Two proposed changes to the charm. Two proposed changes to the charm:

• Make the config changed function only restart the service if it's already running
• Improve the config changed hook function to consider how many configs were changed, and only restart after all changes have been completed

Screenshot:

[ZeeshanM96]

Two comments:

• Maybe you've already seen it, maybe not, but similar functionality is implemented in the zkEVM charm in case you want to check it out for inspiration.
• utils.install_binary(self.config, service_args_obj.chain_name) also contains stop_service, so there's some more stuff to adjust there.

utils.install_binary does contain stop-service, but aren't we concerned about start_service, aim is to stop the service from starting when a service args are changed. Please correct me if I am wrong!

[jakobilobi]

@Maharacha @jonathanudd

I say we close this and take another stab at another time, if we feel the need for it. Agree?

[jonathanudd]

@Maharacha @jonathanudd

I say we close this and take another stab at another time, if we feel the need for it. Agree?

Sounds good. The card will still be there for later :)

[Maharacha]

@Maharacha @jonathanudd

I say we close this and take another stab at another time, if we feel the need for it. Agree?

Agree. It was not close to a working solution anyway.