io.journalkeeper.core.server.VoterConfigManager Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of journalkeeper-core Show documentation
Show all versions of journalkeeper-core Show documentation
Journalkeeper core raft implementations.
/**
* Licensed 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 io.journalkeeper.core.server;
import io.journalkeeper.core.api.JournalEntry;
import io.journalkeeper.core.api.JournalEntryParser;
import io.journalkeeper.core.api.ResponseConfig;
import io.journalkeeper.core.api.SerializedUpdateRequest;
import io.journalkeeper.core.api.VoterState;
import io.journalkeeper.core.entry.internal.*;
import io.journalkeeper.core.journal.Journal;
import io.journalkeeper.core.state.ConfigState;
import io.journalkeeper.metric.JMetric;
import io.journalkeeper.rpc.client.ClientServerRpc;
import io.journalkeeper.rpc.client.UpdateClusterStateRequest;
import io.journalkeeper.utils.state.StateServer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.net.URI;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Callable;
import java.util.stream.Collectors;
import static io.journalkeeper.core.api.RaftJournal.INTERNAL_PARTITION;
import static io.journalkeeper.core.entry.internal.InternalEntryType.*;
/**
* @author LiYue
* Date: 2019-09-10
*/
public class VoterConfigManager {
private static final Logger logger = LoggerFactory.getLogger(VoterConfigManager.class);
private final JournalEntryParser journalEntryParser;
VoterConfigManager(JournalEntryParser journalEntryParser) {
this.journalEntryParser = journalEntryParser;
}
boolean maybeUpdateLeaderConfig(SerializedUpdateRequest request,
ConfigState votersConfigStateMachine,
Journal journal,
Callable appendEntryCallable,
URI serverUri,
List followers,
int replicationParallelism,
Map appendEntriesRpcMetricMap) throws Exception {
// 如果是配置变更请求，立刻更新当前配置
if(request.getPartition() == INTERNAL_PARTITION){
InternalEntryType entryType = InternalEntriesSerializeSupport.parseEntryType(request.getEntry());
if (entryType == TYPE_UPDATE_VOTERS_S1) {
UpdateVotersS1Entry updateVotersS1Entry = InternalEntriesSerializeSupport.parse(request.getEntry());
// 等待所有日志都被提交才能进行配置变更
waitingForAllEntriesCommitted(journal);
votersConfigStateMachine.toJointConsensus(updateVotersS1Entry.getConfigNew(), appendEntryCallable);
List oldFollowerUriList = followers.stream().map(Leader.ReplicationDestination::getUri).collect(Collectors.toList());
for (URI uri : updateVotersS1Entry.getConfigNew()) {
if (!serverUri.equals(uri) && // uri was not me
!oldFollowerUriList.contains(uri)) { // and not included in the old followers collection
followers.add(new Leader.ReplicationDestination(uri, journal.maxIndex(), replicationParallelism));
}
}
return true;
} else if (entryType == TYPE_UPDATE_VOTERS_S2) {
// 等待所有日志都被提交才能进行配置变更
waitingForAllEntriesCommitted(journal);
votersConfigStateMachine.toNewConfig(appendEntryCallable);
followers.removeIf(follower -> {
if(!votersConfigStateMachine.voters().contains(follower.getUri())){
appendEntriesRpcMetricMap.remove(follower.getUri());
return true;
} else {
return false;
}
});
return true;
}
}
return false;
}
/**
* Block current thread and waiting until all entries were committed。
*/
private void waitingForAllEntriesCommitted(Journal journal) throws InterruptedException {
long t0 = System.nanoTime();
while(journal.commitIndex() < journal.maxIndex()) {
if(System.nanoTime() - t0 < 10000000000L) {
Thread.yield();
} else {
Thread.sleep(10L);
}
}
}
// 如果要删除部分未提交的日志，并且待删除的这部分存在配置变更日志，则需要回滚配置
void maybeRollbackConfig(long startIndex, Journal journal,
ConfigState votersConfigStateMachine) {
if(startIndex >= journal.maxIndex()) {
return;
}
long index = journal.maxIndex(INTERNAL_PARTITION);
long startOffset = journal.readOffset(startIndex);
while (--index >= journal.minIndex(INTERNAL_PARTITION)) {
JournalEntry entry = journal.readByPartition(INTERNAL_PARTITION, index);
if (entry.getOffset() < startOffset) {
break;
}
InternalEntryType reservedEntryType = InternalEntriesSerializeSupport.parseEntryType(entry.getPayload().getBytes());
if(reservedEntryType == TYPE_UPDATE_VOTERS_S2) {
UpdateVotersS2Entry updateVotersS2Entry = InternalEntriesSerializeSupport.parse(entry.getPayload().getBytes());
votersConfigStateMachine.rollbackToJointConsensus(updateVotersS2Entry.getConfigOld());
} else if(reservedEntryType == TYPE_UPDATE_VOTERS_S1) {
votersConfigStateMachine.rollbackToOldConfig();
}
}
}
// 非Leader（Follower和Observer）复制日志到本地后，如果日志中包含配置变更，则立即变更配置
void maybeUpdateNonLeaderConfig(List entries, ConfigState votersConfigStateMachine) throws Exception {
for (byte[] rawEntry : entries) {
JournalEntry entryHeader = journalEntryParser.parseHeader(rawEntry);
if(entryHeader.getPartition() == INTERNAL_PARTITION) {
int headerLength = journalEntryParser.headerLength();
InternalEntryType entryType = InternalEntriesSerializeSupport.parseEntryType(rawEntry, headerLength, rawEntry.length - headerLength);
if (entryType == TYPE_UPDATE_VOTERS_S1) {
UpdateVotersS1Entry updateVotersS1Entry = InternalEntriesSerializeSupport.parse(rawEntry, headerLength, rawEntry.length - headerLength);
votersConfigStateMachine.toJointConsensus(updateVotersS1Entry.getConfigNew(),
() -> null);
} else if (entryType == TYPE_UPDATE_VOTERS_S2) {
votersConfigStateMachine.toNewConfig(() -> null);
}
}
}
}
void applyReservedEntry(InternalEntryType type, byte [] reservedEntry, VoterState voterState,
ConfigState votersConfigStateMachine,
ClientServerRpc clientServerRpc, URI serverUri, StateServer server) {
switch (type) {
case TYPE_UPDATE_VOTERS_S1:
if(voterState == VoterState.LEADER) {
byte[] s2Entry = InternalEntriesSerializeSupport.serialize(new UpdateVotersS2Entry(votersConfigStateMachine.getConfigOld(), votersConfigStateMachine.getConfigNew()));
try {
if (votersConfigStateMachine.isJointConsensus()) {
clientServerRpc.updateClusterState(new UpdateClusterStateRequest(
Collections.singletonList(
new SerializedUpdateRequest(
s2Entry, INTERNAL_PARTITION, 1
)
)
, false, ResponseConfig.ONE_WAY));
} else {
throw new IllegalStateException();
}
} catch (Exception e) {
UpdateVotersS1Entry updateVotersS1Entry = InternalEntriesSerializeSupport.parse(reservedEntry);
logger.warn("Failed to update voter config in step 1! Config in the first step entry from: {} To: {}, " +
"voter config old: {}, new: {}.",
updateVotersS1Entry.getConfigOld(), updateVotersS1Entry.getConfigNew(),
votersConfigStateMachine.getConfigOld(), votersConfigStateMachine.getConfigNew(), e);
}
} else if(!votersConfigStateMachine.voters().contains(serverUri)) {
// Stop myself if I'm no longer a member of the cluster. Any follower can be stopped safely on this stage.
server.stopAsync();
}
break;
case TYPE_UPDATE_VOTERS_S2:
// Stop myself if I'm no longer a member of the cluster.
// Leader can be stopped on this stage, a new leader will be elected in the new configuration.
if(!votersConfigStateMachine.voters().contains(serverUri)) {
server.stopAsync();
}
break;
default:
}
}
}