Hello devs, I would like to open a discussion about considerations regarding how to deprecate CLI actions, and what compatibility guarantees should apply to such cases. The topic came up in a previous discussion [1] about a current FLIP to merge the run and run-application behavior [2].
According to Xintong's previous inputs, currently the Flink CLI, or its actions are not handled as public APIs by the existing definition (@Public or @PublicEvolving annotated). So legally it would be possible to change CLIs anytime. I agree with Xintong that CLI actions should be considered as public APIs, and as such, compatibility guarantees should be provided. CLI actions are defined as private constants in CliFrontend [3], so IMO the existing rules are not perfectly applicable as is. Both @Public and @PublicEvolving can be applied to fields (although for @Public that is only true as per the javadoc, technically it can only be applied to classes), so I think that could be a good approach that is achievable with minimal effort and changes. It would also be possible to define a different process, but IMO the more lightweight and maintainable the process the better, so it is a good thing if it is not necessary to bring in new entities and/or rules to check and enforce compatibility. WDYT? Best, Ferenc [1] https://lists.apache.org/thread/0vc8v3t7fr6w9hmwf9zbjbyk5c3bcj50 [2] https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=311626179 [3] https://github.com/apache/flink/blob/27287a105f6585e89795e2a6cbffa8254abb6e57/flink-clients/src/main/java/org/apache/flink/client/cli/CliFrontend.java#L98
