Add config option to specify zk version in integration tests (#10870)

* Update integration-tests README

Updated the integration-tests README file to include instructions
for setting the `ZK_VERSION` property which is now required to be
set prior to executing any integration test. Also added a note
about the importance of setting the test group parameter when
running integration tests, even when running single tests.

* * revert change made to DOCKER_IP doc

* * Add default value for zk version

* * update travis config to use new zk.version property when running
  integration tests

* Remove doc about needing to set ZK_VERSION variable when running
  integration tests

.travis.yml

@@ -346,7 +346,7 @@ jobs:
         - docker
       env: TESTNG_GROUPS='-Dgroups=batch-index' JVM_RUNTIME='-Djvm.runtime=8' USE_INDEXER='middleManager'
       script: &run_integration_test
-        - ${MVN} verify -pl integration-tests -P integration-tests ${TESTNG_GROUPS} ${JVM_RUNTIME} -Dit.indexer=${USE_INDEXER} ${MAVEN_SKIP}
+        - ${MVN} verify -pl integration-tests -P integration-tests ${TESTNG_GROUPS} ${JVM_RUNTIME} -Dit.indexer=${USE_INDEXER} -Dzk.version=${ZK_VERSION} ${MAVEN_SKIP}
       after_failure: &integration_test_diags
         - for v in ~/shared/logs/*.log ; do
           echo $v logtail ======================== ; tail -100 $v ;

integration-tests/README.md

@@ -56,8 +56,10 @@ To run all tests from a test group using docker and mvn run the following comman
 
 To run only a single test using mvn run the following command:
 ```
-  mvn verify -P integration-tests -Dit.test=<test_name>
+  mvn verify -P integration-tests -Dgroups=<test_group> -Dit.test=<test_name>
 ```
+The test group should always be set, as certain test setup and cleanup tasks are based on the test group. You can find
+the test group for a given test as an annotation in the respective test class.
 
 Add `-rf :druid-integration-tests` when running integration tests for the second time or later without changing
 the code of core modules in between to skip up-to-date checks for the whole module dependency tree.

integration-tests/pom.xml

@@ -393,6 +393,7 @@
                 <docker.build.skip>false</docker.build.skip>
                 <docker.build.hadoop>false</docker.build.hadoop>
                 <it.indexer>middleManager</it.indexer>
+                <zk.version>3.5</zk.version>
                 <override.config.path />
                 <resource.file.dir.path />
 
@@ -423,6 +424,7 @@
                                         <DRUID_INTEGRATION_TEST_SKIP_RUN_DOCKER>${docker.run.skip}</DRUID_INTEGRATION_TEST_SKIP_RUN_DOCKER>
                                         <DRUID_INTEGRATION_TEST_INDEXER>${it.indexer}</DRUID_INTEGRATION_TEST_INDEXER>
                                         <MYSQL_VERSION>${mysql.version}</MYSQL_VERSION>
+                                        <ZK_VERSION>${zk.version}</ZK_VERSION>
                                     </environmentVariables>
                                     <executable>${project.basedir}/build_run_cluster.sh</executable>
                                 </configuration>