Test native support of PyFlink on Kubernetes

General Information about the Flink 1.12 release testing

When testing a feature, consider the following aspects:

• Is the documentation easy to understand
• Are the error messages, log messages, APIs etc. easy to understand
• Is the feature working as expected under normal conditions
• Is the feature working / failing as expected with invalid input, induced errors etc.

If you find a problem during testing, please file a ticket (Priority=Critical; Fix Version = 1.12.0), and link it in this testing ticket.
During the testing keep us updated on tests conducted, or please write a short summary of all things you have tested in the end.