Fixing a failure seen in MessageIdFactoryTest.java

[krishnanand5]

In MessageIdFactoryTest.java, the following test has been found to be flaky:

• com.dianping.cat.message.context.MessageIdFactoryTest.testGivenDomainInParallel.

REASON FOR FLAKINESS:

• The mentioned test is not waiting for all the threads to complete execution.
• The execution of this test depends on com.dianping.cat.message.context.MessageIdFactoryTest.testDefaultDomainInParallel and a similar behaviour is observed in this test as well.

DETECTING THE FLAKINESS:

I used the NonDex tool to verify the flakiness in both the mentioned tests. The steps that can be used to verify the same are as follows:

1. git clone https://github.com/dianping/cat.
2. mvn -pl cat-client install.
3. mvn -pl cat-client edu.illinois:nondex-maven-plugin:2.1.1:nondex -Dtest=com.dianping.cat.message.context.MessageIdFactoryTest#testGivenDomainInParallel.

After executing these steps, the following error will be hit:

 T E S T S
-------------------------------------------------------
Concurrency config is parallel='none', perCoreThreadCount=true, threadCount=2, useUnlimitedThreads=false
Running com.dianping.cat.message.context.MessageIdFactoryTest
Tests run: 6, Failures: 2, Errors: 0, Skipped: 0, Time elapsed: -289,157.592 sec <<< FAILURE!

Results :

Failed tests:   testDefaultDomainInParallel(com.dianping.cat.message.context.MessageIdFactoryTest): Not all threads completed in time. expected:<123400> but was:<38720>
  testGivenDomainInParallel(com.dianping.cat.message.context.MessageIdFactoryTest): Not all threads completed in time. expected:<123400> but was:<29820>

Tests run: 6, Failures: 2, Errors: 0, Skipped: 0

PROPOSED SOLUTION:

• The fix involves waiting for all the threads to complete their executions.
• We can initiate a wait for all jobs to be done using pool.awaitTermination(1, TimeUnit.HOURS);.
• Once all jobs and threads have completed execution, we can proceed to the assertions.
• This way assertions will not fail owing to an inadequate wait time for job completion.