Gujiawei-Edinburgh commented on code in PR #188: URL: https://github.com/apache/bifromq/pull/188#discussion_r2514613239
########## base-kv/base-kv-local-engine-rocksdb/src/main/java/org/apache/bifromq/basekv/localengine/rocksdb/RocksDBKVSpaceMigratableWriter.java: ########## @@ -0,0 +1,71 @@ +/* + * 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.bifromq.basekv.localengine.rocksdb; + +import com.google.protobuf.ByteString; +import java.util.Map; +import java.util.function.Consumer; +import org.apache.bifromq.basekv.localengine.IKVSpaceIterator; +import org.apache.bifromq.basekv.localengine.IKVSpaceMigratableWriter; +import org.apache.bifromq.basekv.localengine.IRestoreSession; +import org.apache.bifromq.basekv.localengine.ISyncContext; +import org.apache.bifromq.basekv.localengine.KVEngineException; +import org.apache.bifromq.basekv.localengine.metrics.KVSpaceOpMeters; +import org.apache.bifromq.basekv.proto.Boundary; +import org.rocksdb.WriteOptions; +import org.slf4j.Logger; + +class RocksDBKVSpaceMigratableWriter extends RocksDBKVSpaceWriter + implements IKVSpaceMigratableWriter { + + RocksDBKVSpaceMigratableWriter(String id, + IRocksDBKVSpaceEpochHandle dbHandle, + RocksDBKVEngine<?> engine, + WriteOptions writeOptions, + ISyncContext syncContext, + IWriteStatsRecorder.IRecorder writeStatsRecorder, + Consumer<Map<ByteString, ByteString>> afterWrite, + KVSpaceOpMeters opMeters, + Logger logger) { + super(id, dbHandle, engine, writeOptions, syncContext, writeStatsRecorder, afterWrite, opMeters, logger); + } + + @Override + public IRestoreSession migrateTo(String targetSpaceId, Boundary boundary) { + try { + RocksDBCPableKVSpace targetKVSpace = (RocksDBCPableKVSpace) engine.createIfMissing(targetSpaceId); + IRestoreSession targetSpaceRestoreSession = targetKVSpace.startRestore((count, bytes) -> + logger.debug("Migrate {} kv to space[{}] from space[{}]: startKey={}, endKey={}", + count, targetSpaceId, id, boundary.getStartKey().toStringUtf8(), + boundary.getEndKey().toStringUtf8())); + try (IKVSpaceIterator itr = new RocksDBKVSpaceIterator(new RocksDBSnapshot(dbHandle, null), boundary, + new IteratorOptions(false, 52428))) { + for (itr.seekToFirst(); itr.isValid(); itr.next()) { Review Comment: During this loop, if an error occurs midway, what happens to the data that has already been flushed in the same loop? Each operation checks `shouldFlush`. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
