xtern commented on code in PR #3058: URL: https://github.com/apache/ignite-3/pull/3058#discussion_r1479655902
########## modules/catalog/src/main/java/org/apache/ignite/internal/catalog/storage/serialization/UpdateLogMarshallerImpl.java: ########## @@ -0,0 +1,116 @@ +/* + * 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.ignite.internal.catalog.storage.serialization; + +import static org.apache.ignite.internal.lang.IgniteStringFormatter.format; + +import org.apache.ignite.internal.catalog.storage.SnapshotEntry; +import org.apache.ignite.internal.catalog.storage.UpdateLogEvent; +import org.apache.ignite.internal.catalog.storage.VersionedUpdate; +import org.apache.ignite.internal.util.io.IgniteUnsafeDataInput; +import org.apache.ignite.internal.util.io.IgniteUnsafeDataOutput; +import org.apache.ignite.lang.MarshallerException; +import org.jetbrains.annotations.TestOnly; + +/** + * Marshaller of update log entries that uses custom serializer. + * + *<p>External serialization was implemented for two reasons: + *<ul> + * <li>Minimize the size of the serialized update log entry.</li> + * <li>Backward compatibility support when changing existing or adding new entry.</li> + * </ul> + * At the moment, the serialization format is specified manually. + * + *<p>While backward compatibility is not required, entities can change arbitrarily without changing the data format version. + * However, every change to an entry's fields requires a change to the serializer that serializes that entry. + * + *<p>Basic format description: + *<pre> + * (size) | description + * ------------------------------ + * 2 | data format version ({@link #PROTOCOL_VERSION}) + * 2 | entry type ({@link VersionedUpdate} or {@link SnapshotEntry}) + * + * [fields of the corresponding event follow (for example, {@link VersionedUpdate}] + * + * 4 | version + * 8 | delayDurationMs + * + * [list of entries follow] + * + * 4 | entries size + * 2 | entry type (see {@link MarshallableEntryType#id()}) + * + * [entry fields follow] Review Comment: Done thanks. -- 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: notifications-unsubscr...@ignite.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
