[DO_NOT_MERGE] Test netty

[zsxwing]

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[SparkQA]

Test build #66925 has finished for PR 15474 at commit f3c8b7d.

• This patch fails build dependency tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #66943 has finished for PR 15474 at commit ca7295e.

• This patch fails PySpark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[srowen]

Yeah, this is what I'm trying now, including putting it in the main flume artifact. No go. The assembly definitely has the class. I think it is somehow not sufficient to put this code in the app classpath with --jars. I mean, we could somehow try to merge the assembly jars into one for Pyspark tests. It is starting to get messy!

[zsxwing]

@srowen I ran the flume python tests locally and didnt find the same issue...

[srowen]

Did you clear your locally built artifacts first? maybe that's the difference. The Jenkins test here hits the same problem I was seeing.

[srowen]

PS I got this to work by making the pyspark tests specify the "userClassPathFirst" flags. I think that's actually reasonable to set. I will try this in my PR at #15436 and hope it works; if so you can close this I think.