>> >> Not sure if this will happen in 1.15 already. We will needed automated >> compatibility tests and a well-defined list of stable API.
> We are > trying to provide forward compatibility: applications using `@Public` APIs > compiled against Flink 1.12.x, should work fine in Flink 1.13.x Unfortunately, I also meet forward compatibility issue, when I do the release 1.14 check, I try to use mysql-cdc connector[1] which compiled against 1.13.1in SQL Client, but it can not work in flink 1.14.0 cluster, it failed due to the metric API compatibility broken. @Public public interface SourceReaderContext { MetricGroup metricGroup(); @Public public interface SourceReaderContext { SourceReaderMetricGroup metricGroup(); Shouldn't we mark it as @Deprecated and then delete it util 2.0.0 version for @Public API as the our community rule [2] described? At least we should keep them across server minor versions (<major>.<minor>.<patch>). Although these changes can be tracked to voted FLIPs and it’s not the fault of a few developers, it show us the fact that we didn’t pay enough attention to back compatibility/forward compatibility. Best, Leonard [1] https://github.com/ververica/flink-cdc-connectors/tree/master/flink-connector-mysql-cdc [2] https://cwiki.apache.org/confluence/display/FLINK/Stability+Annotations