I don’t know if the title correctly captures all that Zookeeper is. But, I think it is close. Zookeeper is not a Message Queue or Message Broker like Apache ActiveMQ, RabbitMQ), Mule, Active Camel, etc. Actually, there is quite a long list there, ZeroMQ could be added to the list too.
But but Zookeeper is something that fits a nice itch one might have when writing distributed applications and wanting to share information amongst them. Surely, a MQ can be used, but what if the data is just configuration or changes to values? A message queue seems a bit heavy. And that is exactly why Zookeeper limits the size of messages.
I like the idea of Zookeeper for apps that have to present life data or share state changes. For example, you have several distributed applications and you want them to know what the other is doing. Or you want them to synchronized on some work, Zookeeper makes this very easy. I don’t know a lot about it yet, but I am getting into it now for my current task.
I will be looking Spring XD and Spring Reactor projects too, so look forward to even posts soon won my adventures in these new technologies. Hopefully I will get my hands on Hadoop too.