…he#6922) (apache#7457)

- Timeout occurred due to initial slow rebalancing.
- Added code to wait until `KafkaStreams` instance is in state RUNNING to check registration of metrics and in state NOT_RUNNING to check deregistration of metrics.
- I removed all other wait conditions, because they are not needed if `KafkaStreams` instance is in the right state.

Reviewers: Guozhang Wang <wangguoz@gmail.com>

Reviewers: Matthias J. Sax <matthias@confluent.io>, Guozhang Wang <guozhang@confluent.io>

…he#7424)

Reviewer: Matthias J. Sax <matthias@confluent.io>

…list (apache#7491)

Author: Konstantine Karantasis <konstantine@confluent.io>
Reviewer: Randall Hauch <rhauch@gmail.com>

…#7392)

Fix bug in Connect REST extension API caused by invalid constructor parameter validation, and update integration test to play nicely with Jenkins

Fix instantiation of TaskState objects by Connect framework.

Author: Chris Egerton <chrise@confluent.io>
Reviewers: Magesh Nandakumar <mageshn@confluent.io>, Randall Hauch <rhauch@gmail.com>

…lizing plugins (apache#7315)

Added plugin isolation unit tests for various scenarios, with a `TestPlugins` class that compiles and builds multiple test plugins without them being on the classpath and verifies that the Plugins and DelegatingClassLoader behave properly. These initially failed for several cases, but now pass since the issues have been fixed.

KAFKA-8340 and KAFKA-8819 are closely related, and this fix corrects the problems reported in both issues.

Author: Greg Harris <gregh@confluent.io>
Reviewers: Chris Egerton <chrise@confluent.io>, Magesh Nandakumar <mageshn@confluent.io>, Konstantine Karantasis <konstantine@confluent.io>, Randall Hauch <rhauch@gmail.com>

Reviewers: Bill Bejeck <bill@confluent.io>, Matthias J. Sax <matthias@confluent.io>

…ct (apache#7511)

The KafkaConsumer Fetcher can sometimes get into an invalid state where it believes that there are ongoing fetch requests, but in fact there are none. This may be caused by the heartbeat thread concurrently handling a disconnection event just after the fetcher thread submits a request which would cause the Fetcher to enter an invalid state where it believes it has ongoing requests to the disconnected node but in fact it does not. This is due to a thread safety issue in the Fetcher where it was possible for the ordering of the modifications to the nodesWithPendingFetchRequests to be incorrect - the Fetcher was adding it after the listener had already been invoked, which would mean that pending node never gets removed again.

This PR addresses that thread safety issue by ensuring that the pending node is added to the nodesWithPendingFetchRequests before the listener is added to the future, ensuring the finally block is called after the node is added.

Reviewers: Tom Lee, Jason Gustafson <jason@confluent.io>, Rajini Sivaram <rajinisivaram@googlemail.com>

)

Same as apache#7537
but targeted at 2.3 for cherry-pick
Reviewers: Bill Bejeck <bbejeck@gmail.com>

…pache#7643)

Reviewers: Guozhang Wang <wangguoz@gmail.com>

…11-9