Github user shralex commented on a diff in the pull request:
https://github.com/apache/zookeeper/pull/292#discussion_r125126374
--- Diff:
src/java/test/org/apache/zookeeper/server/quorum/ReconfigRollingRestartCompatibilityTest.java
---
@@ -0,0 +1,275 @@
+/**
+ * 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 org.apache.zookeeper.server.quorum;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.util.Arrays;
+import java.util.Map;
+import java.util.Set;
+import java.util.List;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.ArrayList;
+
+import org.apache.zookeeper.WatchedEvent;
+import org.apache.zookeeper.ZooKeeper;
+import org.apache.zookeeper.CreateMode;
+import org.apache.zookeeper.ZooDefs;
+import org.apache.zookeeper.PortAssignment;
+import org.apache.zookeeper.KeeperException;
+import org.apache.zookeeper.Watcher;
+import org.apache.zookeeper.test.ClientBase;
+import org.junit.Assert;
+import org.junit.Test;
+
+import static org.apache.zookeeper.test.ClientBase.CONNECTION_TIMEOUT;
+
+/**
+ * ReconfigRollingRestartCompatibilityTest - we want to make sure that
users
+ * can continue using the rolling restart approach when reconfig feature
is disabled.
+ * It is important to stay compatible with rolling restart because dynamic
reconfig
+ * has its limitation: it requires a quorum of server to work. When no
quorum can be formed,
+ * rolling restart is the only approach to reconfigure the ensemble (e.g.
removing bad nodes
+ * such that a new quorum with smaller number of nodes can be formed.).
+ *
+ * See ZOOKEEPER-2819 for more details.
+ */
+public class ReconfigRollingRestartCompatibilityTest extends
QuorumPeerTestBase {
+ private static final String backupFileName = "zoo.cfg.bak";
+
+ Map<Integer, Integer> clientPorts = new HashMap<>(5);
+ Map<Integer, String> serverAddress = new HashMap<>(5);
+
+ private String generateNewQuorumConfig(int serverCount) {
+ StringBuilder sb = new StringBuilder();
+ String server;
+ for (int i = 0; i < serverCount; i++) {
+ clientPorts.put(i, PortAssignment.unique());
+ server = "server." + i + "=localhost:" +
PortAssignment.unique()
+ + ":" + PortAssignment.unique() +
":participant;localhost:"
+ + clientPorts.get(i);
+ serverAddress.put(i, server);
+ sb.append(server + "\n");
+ }
+ return sb.toString();
+ }
+
+ private String updateExistingQuorumConfig(List<Integer> sidsToAdd,
List<Integer> sidsToRemove) {
+ StringBuilder sb = new StringBuilder();
+ for (Integer sid : sidsToAdd) {
+ clientPorts.put(sid, PortAssignment.unique());
+ serverAddress.put(sid, "server." + sid + "=localhost:" +
PortAssignment.unique()
+ + ":" + PortAssignment.unique() +
":participant;localhost:"
+ + clientPorts.get(sid));
+ }
+
+ for (Integer sid : sidsToRemove) {
+ clientPorts.remove(sid);
+ serverAddress.remove(sid);
+ }
+
+ for (String server : serverAddress.values()) {
+ sb.append(server + "\n");
+ }
+
+ return sb.toString();
+ }
+
+ @Test(timeout = 60000)
+ // Verify no zoo.cfg.dynamic and zoo.cfg.bak files existing locally
+ // when reconfig feature flag is off by default.
+ public void testNoLocalDynamicConfigAndBackupFiles()
+ throws InterruptedException, IOException {
+ int serverCount = 3;
+ String config = generateNewQuorumConfig(serverCount);
+ QuorumPeerTestBase.MainThread mt[] = new
QuorumPeerTestBase.MainThread[serverCount];
+ String[] staticFileContent = new String[serverCount];
+
+ for (int i = 0; i < serverCount; i++) {
+ mt[i] = new QuorumPeerTestBase.MainThread(i,
clientPorts.get(i),
+ config, false);
+ mt[i].start();
+ }
+
+ for (int i = 0; i < serverCount; i++) {
+ Assert.assertTrue("waiting for server " + i + " being up",
+ ClientBase.waitForServerUp("127.0.0.1:" +
clientPorts.get(i),
+ CONNECTION_TIMEOUT));
+ Assert.assertNull("static file backup (zoo.cfg.bak) shouldn't
exist!",
+ mt[i].getFileByName(backupFileName));
+ Assert.assertNull("dynamic configuration file
(zoo.cfg.dynamic.*) shouldn't exist!",
+
mt[i].getFileByName(mt[i].getQuorumPeer().getNextDynamicConfigFilename()));
+ staticFileContent[i] =
Files.readAllLines(mt[i].confFile.toPath(), StandardCharsets.UTF_8).toString();
+ Assert.assertTrue("static config file should contain server
entry " + serverAddress.get(i),
+ staticFileContent[i].contains(serverAddress.get(i)));
+ }
+
+ for (int i = 0; i < serverCount; i++) {
+ mt[i].shutdown();
+ }
+ }
+
+ @Test(timeout = 60000)
+ // This test simulate the usual rolling restart with no membership
change:
+ // 1. A node is shutdown first (e.g. to upgrade software, or hardware,
or cleanup local data.).
+ // 2. After upgrade, start the node.
+ // 3. Do this for every node, one at a time.
+ public void testRollingRestartWithoutMembershipChange()
+ throws IOException, InterruptedException, KeeperException {
+ int serverCount = 3;
+ String config = generateNewQuorumConfig(serverCount);
+ QuorumPeerTestBase.MainThread mt[] = new
QuorumPeerTestBase.MainThread[serverCount];
+ for (int i = 0; i < serverCount; ++i) {
+ mt[i] = new QuorumPeerTestBase.MainThread(i,
clientPorts.get(i),
+ config, false);
+ mt[i].start();
+ }
+
+ for (int i = 0; i < serverCount; ++i) {
+ Assert.assertTrue("waiting for server " + i + " being up",
+ ClientBase.waitForServerUp("127.0.0.1:" +
clientPorts.get(i),
+ CONNECTION_TIMEOUT));
+ }
+
+ for (int i = 0; i < serverCount; ++i) {
+ mt[i].shutdown();
+ mt[i].start();
+ verifyQuorum(i);
+ verifyConfig(mt[i]);
+ }
+
+ for (int i = 0; i < serverCount; i++) {
+ mt[i].shutdown();
+ }
+ }
+
+ @Test(timeout = 90000)
+ // This test simulate the use case of change of membership through
rolling
+ // restart. For a 3 node ensemble we expand it to a 5 node ensemble,
verify
+ // during the process each node has the expected configuration setting
pushed
+ // via updating local zoo.cfg file.
+ public void testRollingRestartWithMembershipChange()
+ throws IOException, InterruptedException, KeeperException {
+ int serverCount = 3;
+ String config = generateNewQuorumConfig(serverCount);
+ QuorumPeerTestBase.MainThread mt[] = new
QuorumPeerTestBase.MainThread[serverCount];
+ for (int i = 0; i < serverCount; ++i) {
+ mt[i] = new QuorumPeerTestBase.MainThread(i,
clientPorts.get(i),
+ config, false);
+ mt[i].start();
+ }
+
+ for (int i = 0; i < serverCount; ++i) {
+ Assert.assertTrue("waiting for server " + i + " being up",
+ ClientBase.waitForServerUp("127.0.0.1:" +
clientPorts.get(i),
+ CONNECTION_TIMEOUT));
+ }
+
+ for (int i = 0; i < serverCount; ++i) {
+ verifyQuorum(i);
+ verifyConfig(mt[i]);
+ }
+
+ Map<Integer, String> oldServerAddress = new
HashMap<>(serverAddress);
+ config = updateExistingQuorumConfig(Arrays.asList(3, 4), new
ArrayList<Integer>());
+ serverCount = serverAddress.size();
+ Assert.assertEquals("Server count should be 5 after config
update.", serverCount, 5);
+
+ mt = Arrays.copyOf(mt, mt.length + 2);
+ for (int i = 3; i < 5; ++i) {
+ mt[i] = new QuorumPeerTestBase.MainThread(i,
clientPorts.get(i),
+ config, false);
+ mt[i].start();
+ Assert.assertTrue("waiting for server " + i + " being up",
+ ClientBase.waitForServerUp("127.0.0.1:" +
clientPorts.get(i),
+ CONNECTION_TIMEOUT));
+ verifyConfig(mt[i]);
+ verifyQuorum(i);
+ }
+
+ Set<String> expectedConfigs = new HashSet<>();
+ for (String conf : oldServerAddress.values()) {
+ // Remove "server.x=" prefix.
+ expectedConfigs.add(conf.substring(9));
+ }
+
+ for (int i = 0; i < 3; ++i) {
+ verifyConfig(mt[i], expectedConfigs);
+ }
+
+ for (int i = 0; i < serverCount; ++i) {
+ mt[i].shutdown();
+ }
+ }
+
+ // A successful write operation indicates a quorum is up.
+ private void verifyQuorum(int sid)
+ throws IOException, InterruptedException, KeeperException {
+ ZooKeeper zk = new ZooKeeper("127.0.0.1:" + clientPorts.get(sid),
+ ClientBase.CONNECTION_TIMEOUT, new Watcher() {
+ public void process(WatchedEvent event) {
+ }});
+
+ for (int j = 0; j < 30; j++) {
+ try {
+ zk.create("/" + Integer.toString(sid) + "." +
Math.random(),
+ "foobar".getBytes(),
+ ZooDefs.Ids.OPEN_ACL_UNSAFE,
CreateMode.PERSISTENT);
+ break;
+ } catch (KeeperException.ConnectionLossException e) {
+ if (j < 29) {
+ Thread.sleep(1000);
+ } else {
+ Assert.fail("client could not connect to reestablished
quorum: " +
+ "giving up after 30+ seconds.");
+ }
+ }
+ }
+ }
+
+ private void verifyConfig(QuorumPeerTestBase.MainThread mt) {
+ Set<String> expectedConfigs = new HashSet<>();
+ for (String config : serverAddress.values()) {
+ // Remove "server.x=" prefix.
+ expectedConfigs.add(config.substring(9));
--- End diff --
this seems fragile (works only for single digit ids, perhaps use the index
of "="
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
