/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.alibaba.wasp.master;
import com.alibaba.wasp.DeserializationException;
import com.alibaba.wasp.EntityGroupInfo;
import com.alibaba.wasp.EntityGroupTransaction;
import com.alibaba.wasp.ServerName;
import com.alibaba.wasp.executor.EventHandler.EventType;
import com.alibaba.wasp.zookeeper.ZKAssign;
import com.alibaba.wasp.zookeeper.ZKUtil;
import com.alibaba.wasp.zookeeper.ZooKeeperWatcher;
import org.apache.zookeeper.KeeperException;
import static org.junit.Assert.assertNotSame;
/**
* Package scoped mocking utility.
*/
public class Mocking {
static void waitForEntityGroupPendingOpenInRIT(AssignmentManager am, String encodedName)
throws InterruptedException {
// We used to do a check like this:
//!Mocking.verifyEntityGroupState(this.watcher, ENTITYGROUPINFO, EventType.M_ZK_ENTITYGROUP_OFFLINE)) {
// There is a race condition with this: because we may do the transition to
// FSERVER_ZK_ENTITYGROUP_OPENING before the RIT is internally updated. We need to wait for the
// RIT to be as we need it to be instead. This cannot happen in a real cluster as we
// update the RIT before sending the openEntityGroup request.
boolean wait = true;
while (wait) {
EntityGroupState state = am.getEntityGroupStates()
.getEntityGroupsInTransition().get(encodedName);
if (state != null && state.isPendingOpen()){
wait = false;
} else {
Thread.sleep(1);
}
}
}
/**
* Fakes the regionserver-side zk transitions of a region open.
* @param w ZooKeeperWatcher to use.
* @param sn Name of the regionserver doing the 'opening'
* @param egInfo EntityGroup we're 'opening'.
* @throws org.apache.zookeeper.KeeperException
* @throws com.alibaba.wasp.DeserializationException
*/
static void fakeEntityGroupServerEntityGroupOpenInZK(FMaster master, final ZooKeeperWatcher w,
final ServerName sn, final EntityGroupInfo egInfo)
throws KeeperException, DeserializationException, InterruptedException {
// Wait till the we region is ready to be open in RIT.
waitForEntityGroupPendingOpenInRIT(master.getAssignmentManager(), egInfo.getEncodedName());
// Get current versionid else will fail on transition from OFFLINE to OPENING below
int versionid = ZKAssign.getVersion(w, egInfo);
assertNotSame(-1, versionid);
// This uglyness below is what the openregionhandler on FSERVER side does. I
// looked at exposing the method over in openregionhandler but its just a
// one liner and its deep over in another package so just repeat it below.
versionid = ZKAssign.transitionNode(w, egInfo, sn,
EventType.M_ZK_ENTITYGROUP_OFFLINE, EventType.FSERVER_ZK_ENTITYGROUP_OPENING, versionid);
assertNotSame(-1, versionid);
// Move znode from OPENING to OPENED as FSERVER does on successful open.
versionid = ZKAssign.transitionNodeOpened(w, egInfo, sn, versionid);
assertNotSame(-1, versionid);
// We should be done now. The master open handler will notice the
// transition and remove this regions znode.
}
/**
* Verifies that the specified region is in the specified state in ZooKeeper.
* <p>
* Returns true if region is in transition and in the specified state in
* ZooKeeper. Returns false if the region does not exist in ZK or is in
* a different state.
* <p>
* Method synchronizes() with ZK so will yield an up-to-date result but is
* a slow read.
* @param zkw
* @param region
* @param expectedState
* @return true if region exists and is in expected state
* @throws com.alibaba.wasp.DeserializationException
*/
static boolean verifyEntityGroupState(ZooKeeperWatcher zkw, EntityGroupInfo region, EventType expectedState)
throws KeeperException, DeserializationException {
String encoded = region.getEncodedName();
String node = ZKAssign.getNodeName(zkw, encoded);
zkw.sync(node);
// Read existing data of the node
byte [] existingBytes = null;
try {
existingBytes = ZKUtil.getDataAndWatch(zkw, node);
} catch (KeeperException.NoNodeException nne) {
return false;
} catch (KeeperException e) {
throw e;
}
if (existingBytes == null) return false;
EntityGroupTransaction rt = EntityGroupTransaction.parseFrom(existingBytes);
return rt.getEventType().equals(expectedState);
}
}