Eliminate nullness errors in KafkaIO

[kennknowles]

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[kennknowles]

R: @johnjcasey

We discussed some cases.

This one I did a lot more "just add an assertion" style fixes, whereas usually I like to refactor things to eliminate the possibility of any error occurring. If you can spot places where it simply doesn't make sense to have a nullable field, please comment.

[johnjcasey]

I don't think these two should ever be null

[kennknowles]

Done

[johnjcasey]

it isn't meaningful to have Kafka config without bootstrap servers, so this should throw an exception if it is null

[kennknowles]

Done

[kennknowles]

And in getting tests to pass, I found that they simply didn't call setup(), so now the tests are more accurate to real usage.

[johnjcasey]

And in getting tests to pass, I found that they simply didn't call setup(), so now the tests are more accurate to real usage.

That is very appreciated

[kennknowles]

run java precommit

[kennknowles]

run java precommit

[kennknowles]

Run Python_PVR_Flink PreCommit

[kennknowles]

Run Python_PVR_Flink PreCommit

[kennknowles]

seeing "could not find valid docker environment" across a lot of PRs, hmm

[kennknowles]

Run Java PreCommit

[kennknowles]

And across many PRs also org.apache.beam.sdk.io.pulsar.PulsarIOTest.testReadFromSimpleTopic: Trying to claim offset 1655305408194 while last attempted was 1655305409570

[kennknowles]

Run Java PreCommit

[kennknowles]

Run Java PreCommit

[kennknowles]

Run Python_PVR_Flink PreCommit

[kennknowles]

no error in the logs, and scan failed to upload :-/

[kennknowles]

Run Python_PVR_Flink PreCommit

[kennknowles]

Please take another look now that tests are green.

Reminder of policy: when a committer is the author, they are trusted to choose the best reviewer, including not-yet-committers. I think you are the best choice for this region of the code. And thanks for the review so far!

[johnjcasey]

This LGTM. Thank you for adding all these checks.