SML0127 commented on code in PR #4104: URL: https://github.com/apache/flink-cdc/pull/4104#discussion_r2328626087
########## flink-cdc-connect/flink-cdc-source-connectors/flink-connector-mysql-cdc/src/main/java/org/apache/flink/cdc/connectors/mysql/source/utils/SnapshotFilterUtils.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.flink.cdc.connectors.mysql.source.utils; + +import org.apache.flink.cdc.common.schema.Selectors; + +import io.debezium.relational.TableId; + +import java.util.HashMap; +import java.util.Map; + +/** Utilities to filter snapshot of table. */ +public class SnapshotFilterUtils { + + private SnapshotFilterUtils() {} + + private static final Map<Map<String, String>, Map<Selectors, String>> cache = new HashMap<>(); + + /** + * Don't worry about atomicity. We don't need to use the synchronized keyword to ensure thread + * safety here. Since filters come from the source configuration, they shouldn’t be changed + * during runtime. So the result will always be idempotent. + */ + private static Map<Selectors, String> toSelector(Map<String, String> filters) { + Map<Selectors, String> cached = cache.get(filters); + if (cached != null) { + return cached; + } + + Map<Selectors, String> snapshotFilters = new HashMap<>(); + filters.forEach( + (table, filter) -> { + Selectors selector = + new Selectors.SelectorsBuilder().includeTables(table).build(); + snapshotFilters.put(selector, filter); + }); + cache.put(filters, snapshotFilters); + + return snapshotFilters; + } + + public static String getSnapshotFilter(Map<String, String> filters, TableId tableId) { + Map<Selectors, String> snapshotFilters = toSelector(filters); + + String filter = null; + for (Selectors selector : snapshotFilters.keySet()) { + if (selector.isMatch( + org.apache.flink.cdc.common.event.TableId.tableId( + tableId.catalog(), tableId.table()))) { + filter = snapshotFilters.get(selector); + break; + } Review Comment: Can we fail fast on unknown/nonexiststent columns in filters? -- 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: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
