improve client testability - allow test client to access connected server 

                 Key: ZOOKEEPER-544
             Project: Zookeeper
          Issue Type: Improvement
          Components: c client, java client, tests
            Reporter: Patrick Hunt
             Fix For: 3.3.0

This came up recently on the user list. If you are developing tests for your zk 
client you need to be able to access the server that your
session is currently connected to. The reason is that your test needs to know 
which server in the quorum to shutdown in order to
verify you are handling failover correctly. Similar for session expiration 

however we should be careful, we prefer not to expose this to all clients, this 
is an implementation detail that we typically
want to hide. 

also we should provide this in both the c and java clients

I suspect we should add a protected method on ZooKeeper. This will make a 
higher bar (user will have to subclass) for 
the user to access this method. In tests it's fine, typically you want a 
"TestableZooKeeper" class anyway. In c we unfortunately
have less options, we can just rely on docs for now. 

In both cases (c/java) we need to be very very clear in the docs that this is 
for testing only and to clearly define semantics.

We should add the following at the same time:

toString() method to ZooKeeper which includes server ip/port, client port, any 
other information deemed useful (connection stats like send/recv?)

the java ZooKeeper is missing "deterministic connection order" that the c 
client has. this is also useful for testing. again, protected and 
clear docs that this is for testing purposes only!

Any other things we should expose?

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

Reply via email to