LeaderElection

[Trym R. Møller]

Hi

Messing with behaviour when Solr looses its ZooKeeper connection I'm 
trying to reproduce how a replica slice gets leader. I have made the 
below unit test in the LeaderElectionTest class which fails.
I don't know if this simulates how Solr uses the LeaderElection class 
but please comment on the scenario.

Thanks in advance.

Best regards Trym

  @Test
  public void testMemoryElection() throws Exception {
    LeaderElector first = new LeaderElector(zkClient);
    ZkNodeProps props = new ZkNodeProps(ZkStateReader.BASE_URL_PROP,
        "http://127.0.0.1/solr/";, ZkStateReader.CORE_NAME_PROP, "1");
    ElectionContext firstContext = new 
ShardLeaderElectionContextBase(first,
        "slice1", "collection2", "dummynode1", props, zkStateReader);
    first.setup(firstContext);
    first.joinElection(firstContext);

    Thread.sleep(1000);
    assertEquals("original leader was not registered", 
"http://127.0.0.1/solr/1/";, getLeaderUrl("collection2", "slice1"));

    SolrZkClient zkClient2 = new SolrZkClient(server.getZkAddress(), 
TIMEOUT);
    LeaderElector second = new LeaderElector(zkClient2);
    props = new ZkNodeProps(ZkStateReader.BASE_URL_PROP,
        "http://127.0.0.1/solr/";, ZkStateReader.CORE_NAME_PROP, "2");
    ElectionContext context = new ShardLeaderElectionContextBase(second,
        "slice1", "collection2", "dummynode1", props, zkStateReader);
    second.setup(context);
    second.joinElection(context);
    Thread.sleep(1000);
    assertEquals("original leader should have stayed leader", 
"http://127.0.0.1/solr/1/";, getLeaderUrl(zkClient2, "collection2", 
"slice1"));

    server.expire(zkClient.getSolrZooKeeper().getSessionId());

    assertEquals("new leader was not registered", 
"http://127.0.0.1/solr/2/";, getLeaderUrl(zkClient2, "collection2", 
"slice1"));
  }