[fix][schema] Reject unsupported Avro schema types during schema registration

[poorbarcode]

Motivation

Issue

• User can upload an Avro-Union schema by pulsar-admin API
• However, the schema uploaded can not be used, users will get an error "Not a record" when creating a producer with AUTO_PRODUCE schema.

Modifications

• Deny uploading an Avro-Union schema
• Improve the logs when creating a producer failed due to an invalidated schema

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository: x

[lhotari]

LGTM, good work @poorbarcode

[lhotari]

I renamed the title to "Reject unsupported Avro schema types during schema registration" since good PR titles are optimally expressed in imperative mood, like good commit messages. The PR title shouldn't be a description of the problem it's fixing. It might be better to file a separate issue where that could be a title of the issue itself.

[poorbarcode]

/pulsarbot rerun-failure-checks

[poorbarcode]

/pulsarbot rerun-failure-checks

[lhotari]

There's a test failure:

  Error:  Tests run: 175, Failures: 1, Errors: 0, Skipped: 165, Time elapsed: 46.633 s <<< FAILURE! - in org.apache.pulsar.broker.admin.AdminApiSchemaTest
  Error:  org.apache.pulsar.broker.admin.AdminApiSchemaTest.testInvalidSchemaDataException[V1](4)  Time elapsed: 0.01 s  <<< FAILURE!
  java.lang.AssertionError: expected [422] but found [500]
  	at org.testng.Assert.fail(Assert.java:110)
  	at org.testng.Assert.failNotEquals(Assert.java:1577)
  	at org.testng.Assert.assertEqualsImpl(Assert.java:149)
  	at org.testng.Assert.assertEquals(Assert.java:131)
  	at org.testng.Assert.assertEquals(Assert.java:1418)
  	at org.testng.Assert.assertEquals(Assert.java:1382)
  	at org.testng.Assert.assertEquals(Assert.java:1428)
  	at org.apache.pulsar.broker.admin.AdminApiSchemaTest.testInvalidSchemaDataException(AdminApiSchemaTest.java:282)
  	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
  	at java.base/java.lang.reflect.Method.invoke(Method.java:580)
  	at org.testng.internal.invokers.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:139)
  	at org.testng.internal.invokers.InvokeMethodRunnable.runOne(InvokeMethodRunnable.java:47)
  	at org.testng.internal.invokers.InvokeMethodRunnable.call(InvokeMethodRunnable.java:76)
  	at org.testng.internal.invokers.InvokeMethodRunnable.call(InvokeMethodRunnable.java:11)
  	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
  	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
  	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
  	at java.base/java.lang.Thread.run(Thread.java:1583)

It seems that 422 Unprocessable Content status is expected.