Versioning of config files deployed in Production

Hi All,

I'm creating a new web service in Rust that will be deployed on the cloud. The application will read its configuration from a set of TOML config files. I'm adding live config update support in the service so that I can change application behavior in production by deploying new config files.

One of the requirements of the design is to support versioning of these config files as there will be many instances of my applications running in the cloud and I would like to get telemetry about which specific instance in production is using which version of configuration file. What's the best way to achieve that? I can manually add version number to the config files but there has to be a better solution to this problem.