Java tutorial
/* * 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 gobblin.source.extractor.extract.jdbc; import java.io.IOException; import java.util.ArrayList; import java.util.Arrays; import java.util.Iterator; import java.util.List; import java.util.Map; import org.apache.commons.lang3.StringUtils; import com.google.common.collect.ImmutableMap; import com.google.gson.JsonElement; import gobblin.configuration.ConfigurationKeys; import gobblin.configuration.WorkUnitState; import gobblin.source.extractor.DataRecordException; import gobblin.source.extractor.exception.HighWatermarkException; import gobblin.source.extractor.exception.RecordCountException; import gobblin.source.extractor.exception.SchemaException; import gobblin.source.extractor.extract.Command; import gobblin.source.extractor.utils.Utils; import gobblin.source.extractor.watermark.Predicate; import gobblin.source.extractor.watermark.WatermarkType; import gobblin.source.workunit.WorkUnit; import lombok.extern.slf4j.Slf4j; /** * MySql extractor using JDBC protocol * * @author nveeramr */ @Slf4j public class MysqlExtractor extends JdbcExtractor { private static final String MYSQL_TIMESTAMP_FORMAT = "yyyy-MM-dd HH:mm:ss"; private static final String MYSQL_DATE_FORMAT = "yyyy-MM-dd"; private static final String MYSQL_HOUR_FORMAT = "HH"; private static final long SAMPLERECORDCOUNT = -1; public MysqlExtractor(WorkUnitState workUnitState) { super(workUnitState); } @Override public String getHourPredicateCondition(String column, long value, String valueFormat, String operator) { log.debug("Getting hour predicate for Mysql"); String formattedvalue = Utils.toDateTimeFormat(Long.toString(value), valueFormat, MYSQL_HOUR_FORMAT); return Utils.getCoalesceColumnNames(column) + " " + operator + " '" + formattedvalue + "'"; } @Override public String getDatePredicateCondition(String column, long value, String valueFormat, String operator) { log.debug("Getting date predicate for Mysql"); String formattedvalue = Utils.toDateTimeFormat(Long.toString(value), valueFormat, MYSQL_DATE_FORMAT); return Utils.getCoalesceColumnNames(column) + " " + operator + " '" + formattedvalue + "'"; } @Override public String getTimestampPredicateCondition(String column, long value, String valueFormat, String operator) { log.debug("Getting timestamp predicate for Mysql"); String formattedvalue = Utils.toDateTimeFormat(Long.toString(value), valueFormat, MYSQL_TIMESTAMP_FORMAT); return Utils.getCoalesceColumnNames(column) + " " + operator + " '" + formattedvalue + "'"; } @Override public List<Command> getSchemaMetadata(String schema, String entity) throws SchemaException { log.debug("Build query to get schema"); List<Command> commands = new ArrayList<>(); List<String> queryParams = Arrays.asList(entity, schema); String metadataSql = "select " + " col.column_name, " + " col.data_type, " + " case when CHARACTER_OCTET_LENGTH is null then 0 else 0 end as length, " + " case when NUMERIC_PRECISION is null then 0 else NUMERIC_PRECISION end as precesion, " + " case when NUMERIC_SCALE is null then 0 else NUMERIC_SCALE end as scale, " + " case when is_nullable='NO' then 'false' else 'true' end as nullable, " + " '' as format, " + " case when col.column_comment is null then '' else col.column_comment end as comment " + " from information_schema.COLUMNS col " + " WHERE upper(col.table_name)=upper(?) AND upper(col.table_schema)=upper(?) " + " order by col.ORDINAL_POSITION "; commands.add(JdbcExtractor.getCommand(metadataSql, JdbcCommand.JdbcCommandType.QUERY)); commands.add(JdbcExtractor.getCommand(queryParams, JdbcCommand.JdbcCommandType.QUERYPARAMS)); return commands; } @Override public List<Command> getHighWatermarkMetadata(String schema, String entity, String watermarkColumn, List<Predicate> predicateList) throws HighWatermarkException { log.debug("Build query to get high watermark"); List<Command> commands = new ArrayList<>(); String columnProjection = "max(" + Utils.getCoalesceColumnNames(watermarkColumn) + ")"; String watermarkFilter = this.concatPredicates(predicateList); String query = this.getExtractSql(); if (StringUtils.isBlank(watermarkFilter)) { watermarkFilter = "1=1"; } query = query.replace(this.getOutputColumnProjection(), columnProjection) .replace(ConfigurationKeys.DEFAULT_SOURCE_QUERYBASED_WATERMARK_PREDICATE_SYMBOL, watermarkFilter); commands.add(JdbcExtractor.getCommand(query, JdbcCommand.JdbcCommandType.QUERY)); return commands; } @Override public List<Command> getCountMetadata(String schema, String entity, WorkUnit workUnit, List<Predicate> predicateList) throws RecordCountException { log.debug("Build query to get source record count"); List<Command> commands = new ArrayList<>(); String columnProjection = "COUNT(1)"; String watermarkFilter = this.concatPredicates(predicateList); String query = this.getExtractSql(); if (StringUtils.isBlank(watermarkFilter)) { watermarkFilter = "1=1"; } query = query.replace(this.getOutputColumnProjection(), columnProjection) .replace(ConfigurationKeys.DEFAULT_SOURCE_QUERYBASED_WATERMARK_PREDICATE_SYMBOL, watermarkFilter); String sampleFilter = this.constructSampleClause(); query = query + sampleFilter; if (!StringUtils.isEmpty(sampleFilter)) { query = "SELECT COUNT(1) FROM (" + query.replace(" COUNT(1) ", " 1 ") + ")temp"; } commands.add(JdbcExtractor.getCommand(query, JdbcCommand.JdbcCommandType.QUERY)); return commands; } @Override public List<Command> getDataMetadata(String schema, String entity, WorkUnit workUnit, List<Predicate> predicateList) throws DataRecordException { log.debug("Build query to extract data"); List<Command> commands = new ArrayList<>(); int fetchsize = Integer.MIN_VALUE; String watermarkFilter = this.concatPredicates(predicateList); String query = this.getExtractSql(); if (StringUtils.isBlank(watermarkFilter)) { watermarkFilter = "1=1"; } query = query.replace(ConfigurationKeys.DEFAULT_SOURCE_QUERYBASED_WATERMARK_PREDICATE_SYMBOL, watermarkFilter); String sampleFilter = this.constructSampleClause(); query = query + sampleFilter; commands.add(JdbcExtractor.getCommand(query, JdbcCommand.JdbcCommandType.QUERY)); commands.add(JdbcExtractor.getCommand(fetchsize, JdbcCommand.JdbcCommandType.FETCHSIZE)); return commands; } @Override public String getConnectionUrl() { String host = this.workUnitState.getProp(ConfigurationKeys.SOURCE_CONN_HOST_NAME); String port = this.workUnitState.getProp(ConfigurationKeys.SOURCE_CONN_PORT); String database = this.workUnitState.getProp(ConfigurationKeys.SOURCE_QUERYBASED_SCHEMA); String url = "jdbc:mysql://" + host.trim() + ":" + port + "/" + database.trim(); if (Boolean .valueOf(this.workUnitState.getProp(ConfigurationKeys.SOURCE_QUERYBASED_IS_COMPRESSION_ENABLED))) { return url + "?useCompression=true"; } return url; } /** {@inheritdoc} */ @Override protected boolean convertBitToBoolean() { return false; } @Override public Map<String, String> getDataTypeMap() { Map<String, String> dataTypeMap = ImmutableMap.<String, String>builder().put("tinyint", "int") .put("smallint", "int").put("mediumint", "int").put("int", "int").put("bigint", "long") .put("float", "float").put("double", "double").put("decimal", "double").put("numeric", "double") .put("date", "date").put("timestamp", "timestamp").put("datetime", "timestamp").put("time", "time") .put("char", "string").put("varchar", "string").put("varbinary", "string").put("text", "string") .put("tinytext", "string").put("mediumtext", "string").put("longtext", "string") .put("blob", "string").put("tinyblob", "string").put("mediumblob", "string") .put("longblob", "string").put("enum", "string").build(); return dataTypeMap; } @Override public String getWatermarkSourceFormat(WatermarkType watermarkType) { String columnFormat = null; switch (watermarkType) { case TIMESTAMP: columnFormat = "yyyy-MM-dd HH:mm:ss"; break; case DATE: columnFormat = "yyyy-MM-dd"; break; default: log.error("Watermark type " + watermarkType.toString() + " not recognized"); } return columnFormat; } @Override public long exractSampleRecordCountFromQuery(String query) { if (StringUtils.isBlank(query)) { return SAMPLERECORDCOUNT; } long recordcount = SAMPLERECORDCOUNT; String limit = null; String inputQuery = query.toLowerCase(); int limitIndex = inputQuery.indexOf(" limit "); if (limitIndex > 0) { limit = query.substring(limitIndex + 7).trim(); } if (StringUtils.isNotBlank(limit)) { try { recordcount = Long.parseLong(limit); } catch (Exception e) { log.error("Ignoring incorrct limit value in input query:" + limit); } } return recordcount; } @Override public String removeSampleClauseFromQuery(String query) { if (StringUtils.isBlank(query)) { return null; } String limitString = ""; String inputQuery = query.toLowerCase(); int limitIndex = inputQuery.indexOf(" limit"); if (limitIndex > 0) { limitString = query.substring(limitIndex); } return query.replace(limitString, ""); } @Override public String constructSampleClause() { long sampleRowCount = this.getSampleRecordCount(); if (sampleRowCount >= 0) { return " limit " + sampleRowCount; } return ""; } @Override public Iterator<JsonElement> getRecordSetFromSourceApi(String schema, String entity, WorkUnit workUnit, List<Predicate> predicateList) throws IOException { return null; } }