@Test
public void testRegionTransitionOperations() throws Exception {
MiniHBaseCluster cluster = UTIL.getHBaseCluster();
HMaster master = cluster.getMaster();
MasterCoprocessorHost host = master.getCoprocessorHost();
CPMasterObserver cp = (CPMasterObserver)host.findCoprocessor(
CPMasterObserver.class.getName());
cp.enableBypass(false);
cp.resetStates();
HTable table = UTIL.createTable(TEST_TABLE, TEST_FAMILY);
UTIL.createMultiRegions(table, TEST_FAMILY);
UTIL.waitUntilAllRegionsAssigned(TEST_TABLE);
NavigableMap<HRegionInfo, ServerName> regions = table.getRegionLocations();
Map.Entry<HRegionInfo, ServerName> firstGoodPair = null;
for (Map.Entry<HRegionInfo, ServerName> e: regions.entrySet()) {
if (e.getValue() != null) {
firstGoodPair = e;
break;
}
}
assertNotNull("Found a non-null entry", firstGoodPair);
LOG.info("Found " + firstGoodPair.toString());
// Try to force a move
Collection<ServerName> servers = master.getClusterStatus().getServers();
String destName = null;
String firstRegionHostnamePortStr = firstGoodPair.getValue().toString();
LOG.info("firstRegionHostnamePortStr=" + firstRegionHostnamePortStr);
boolean found = false;
// Find server that is NOT carrying the first region
for (ServerName info : servers) {
LOG.info("ServerName=" + info);
if (!firstRegionHostnamePortStr.equals(info.getHostAndPort())) {
destName = info.toString();
found = true;
break;
}
}
assertTrue("Found server", found);
LOG.info("Found " + destName);
master.move(firstGoodPair.getKey().getEncodedNameAsBytes(),
Bytes.toBytes(destName));
assertTrue("Coprocessor should have been called on region move",
cp.wasMoveCalled());
// make sure balancer is on
master.balanceSwitch(true);
assertTrue("Coprocessor should have been called on balance switch",
cp.wasBalanceSwitchCalled());
// force region rebalancing
master.balanceSwitch(false);
// move half the open regions from RS 0 to RS 1
HRegionServer rs = cluster.getRegionServer(0);
byte[] destRS = Bytes.toBytes(cluster.getRegionServer(1).getServerName().toString());
//Make sure no regions are in transition now
waitForRITtoBeZero(master);
List<HRegionInfo> openRegions = rs.getOnlineRegions();
int moveCnt = openRegions.size()/2;
for (int i=0; i<moveCnt; i++) {
HRegionInfo info = openRegions.get(i);
if (!info.isMetaTable()) {
master.move(openRegions.get(i).getEncodedNameAsBytes(), destRS);
}
}
//Make sure no regions are in transition now
waitForRITtoBeZero(master);
// now trigger a balance
master.balanceSwitch(true);
boolean balanceRun = master.balance();
assertTrue("Coprocessor should be called on region rebalancing",
cp.wasBalanceCalled());
}