It should also work the other way around. If there is a property which is commented out in yaml and it is not in Config.java, that should fail as well. If it is not commented out and it is not in Config.java, that will fail in runtime as it fails on unrecognized property.
This will be used in practice very rarely as we seldom remove the properties in Config but if we do and a property is commented out, we should not ship a dead property name, even commented out. On Fri, Jan 24, 2025 at 3:51 PM Paulo Motta <pa...@apache.org> wrote: > > > If "# my_cool_property: true" is NOT in cassandra.yaml, we might > indeed add it, also commented out. I think it would be quite easy to check > against yaml if there is a line starting on "# my_cool_property" or just on > "my_cool_property". Both cases would satisfy the check. > > Makes sense, I think this would be good to have as a lint or test to > easily catch overlooks during review. > > > On Fri, Jan 24, 2025 at 9:44 AM Štefan Miklošovič <smikloso...@apache.org> > wrote: > >> >> >> On Fri, Jan 24, 2025 at 3:27 PM Paulo Motta <pa...@apache.org> wrote: >> >>> > from time to time I see configuration properties in Config.java and >>> they are clearly not in cassandra.yaml. Not every property in Config is in >>> cassandra.yaml. I would like to know if there is some specific reason >>> behind that. >>> >>> I think one of the original reasons was to "hide" advanced configs that >>> are not meant to be updated, unless in very niche circumstances. However I >>> think this has been extrapolated to non-advanced settings. >>> >>> > Question related to that is if we could not have a build-time check >>> that all properties in Config have to be in cassandra.yaml and fail the >>> build if a property in Config does not have its counterpart in yaml. >>> >>> Are you saying every configuration property should be commented-out, or >>> do you think that every Config property should be specified in >>> cassandra.yaml with their default uncomented ? One issue with that is that >>> you could cause user confusion if you "reveal" a niche/advanced config that >>> is not meant to be updated. I think this would be addressed by >>> the @HiddenInYaml flag you are proposing in a later post. >>> >> >> Yes, then can stay hidden, but we should annotate it with @Hidden or >> similar. As of now, if that property is not in yaml, we just don't know if >> it was forgotten to be added or if we have not added it on purpose. >> >> They can keep being commented out if they currently are. Imagine a >> property in Config.java >> >> public boolean my_cool_property = true; >> >> and then this in cassandra.yaml >> >> # my_cool_property: true >> >> It is completely ok. >> >> If "# my_cool_property: true" is NOT in cassandra.yaml, we might indeed >> add it, also commented out. I think it would be quite easy to check against >> yaml if there is a line starting on "# my_cool_property" or just on >> "my_cool_property". Both cases would satisfy the check. >> >> >> >>> > There are dozens of properties in Config and I have a strong suspicion >>> that we missed to publish some to yaml so users do not even know such a >>> property exists and as of now we do not even know which they are. >>> >>> I believe this is a problem. I think most properties should be in >>> cassandra.yaml, unless they are very advanced or not meant to be updated. >>> >>> Another tangential issue is that there are features/settings that don't >>> even have a Config entry, but are just controlled by JVM properties. >>> >>> I think that we should attempt to unify Config and jvm properties under >>> a predictable structure. For example, if there is a YAML config >>> enable_user_defined_functions, then there should be a respective JVM flag >>> -Dcassandra.enable_user_defined_functions, and vice versa. >>> >> >> Yeah, good idea. >> >> >>> >>> On Fri, Jan 24, 2025 at 9:16 AM Štefan Miklošovič < >>> smikloso...@apache.org> wrote: >>> >>>> Hello, >>>> >>>> from time to time I see configuration properties in Config.java and >>>> they are clearly not in cassandra.yaml. Not every property in Config is in >>>> cassandra.yaml. I would like to know if there is some specific reason >>>> behind that. >>>> >>>> Question related to that is if we could not have a build-time check >>>> that all properties in Config have to be in cassandra.yaml and fail the >>>> build if a property in Config does not have its counterpart in yaml. >>>> >>>> There are dozens of properties in Config and I have a strong suspicion >>>> that we missed to publish some to yaml so users do not even know such a >>>> property exists and as of now we do not even know which they are. >>>> >>>
