The failback process needs to be deterministic rather than relying on various
incarnations of Thread.sleep() at crucial points. Important aspects of this
change include:
1) Make the initial replication synchronization process block at the very
last step and wait for a response from the replica to ensure the replica has
as the necessary data. This is a critical piece of knowledge during the
failback process because it allows the soon-to-become-backup server to know
for sure when it can shut itself down and allow the soon-to-become-live
server to take over. Also, introduce a new configuration element called
"initial-replication-sync-timeout" to conrol how long this blocking will occur.
2) Set the state of the server as 'LIVE' only after the server is fully
started. This is necessary because once the soon-to-be-backup server shuts
down it needs to know that the soon-to-be-live server has started fully before
it restarts itself as the new backup. If the soon-to-be-backup server restarts
before the soon-to-be-live is fully started then it won't actually become a
backup server but instead will become a live server which will break the
failback process.
3) Wait to receive the announcement of a backup server before failing-back.
After I spent a whole afternoon trying to make IBM JDK to work under IDEA, I decided to add a note on the doc so other would have a chance to have it working faster than I did.
Lots of work on the test-suite in this commit including:
- Rename ServiceTestBase to ActiveMQTestBase
- Make AddressSettings fluent
- Remove unnecessary tearDown() implementations
- Use ActiveMQTestBase.create*Locator() instead of
ActiveMQClient.createServerLocator*(..)
- Use fluent ServerLocator methods
- Make sure all ActiveMQServers.newActiveMQServer invocations
are surrounded with addServer() where appropriate
- Create a few example tests to be references from hacking-guide
- Update hacking-guide with more info on writing tests
- Refactor config creation methods in ActiveMQTestBase
This has bothered me for awhile, but writing the hacking guide has
given me an opportunity to refactor some of our test-suite to be
simpler, more consistent, and easier to understand. This is
important if we want users to provide well-written tests. Our
test-suite is an important part of the code-base and it should be
easy to write good tests.
Basically I just consolidated CoreUnitTestCase, UnitTestCase, and
ServiceTestBase into a single class named ServiceTestBase. I also
simplified some of the configuration creation methods to reduce
duplicated code.
This is changing the default host to 0.0.0.0 per feedback from the community (activemq dev-list)
however if clustered is used some input or other properties will get input during the create process
I've also done some other changes based on some small issues I have encountered
jbertram
Clebert Suconic
Glaucio Melo
Martyn Taylor
Erich Duda
Ville Skyttä
Daniel Kulp
Andy Taylor
Andy Taylor