| /* |
| * 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.iotdb.flink; |
| |
| import org.apache.iotdb.flink.options.IoTDBSourceOptions; |
| import org.apache.iotdb.isession.SessionDataSet; |
| import org.apache.iotdb.rpc.IoTDBConnectionException; |
| import org.apache.iotdb.rpc.StatementExecutionException; |
| import org.apache.iotdb.session.Session; |
| |
| import org.apache.flink.configuration.Configuration; |
| import org.apache.flink.streaming.api.functions.source.RichSourceFunction; |
| import org.apache.tsfile.read.common.RowRecord; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| public abstract class IoTDBSource<T> extends RichSourceFunction<T> { |
| |
| private static final Logger LOG = LoggerFactory.getLogger(IoTDBSource.class); |
| private static final long serialVersionUID = 1L; |
| private IoTDBSourceOptions sourceOptions; |
| |
| private transient Session session; |
| private transient SessionDataSet dataSet; |
| |
| protected IoTDBSource(IoTDBSourceOptions ioTDBSourceOptions) { |
| this.sourceOptions = ioTDBSourceOptions; |
| } |
| |
| @Override |
| public void open(Configuration parameters) throws Exception { |
| super.open(parameters); |
| initSession(); |
| } |
| |
| /** |
| * Convert raw data (in form of RowRecord) extracted from IoTDB to user-defined data type |
| * |
| * @param rowRecord row record from IoTDB |
| * @return object in user-defined form |
| */ |
| public abstract T convert(RowRecord rowRecord); |
| |
| @Override |
| public void run(SourceContext<T> sourceContext) throws Exception { |
| dataSet = session.executeQueryStatement(sourceOptions.getSql()); |
| dataSet.setFetchSize(sourceOptions.getFetchSize()); |
| while (dataSet.hasNext()) { |
| sourceContext.collect(convert(dataSet.next())); |
| } |
| dataSet.closeOperationHandle(); |
| } |
| |
| @Override |
| public void cancel() { |
| try { |
| dataSet.closeOperationHandle(); |
| } catch (StatementExecutionException | IoTDBConnectionException e) { |
| LOG.error(e.getMessage()); |
| } |
| } |
| |
| @Override |
| public void close() throws Exception { |
| super.close(); |
| try { |
| dataSet.closeOperationHandle(); |
| } catch (StatementExecutionException | IoTDBConnectionException e) { |
| throw e; |
| } finally { |
| session.close(); |
| } |
| } |
| |
| void initSession() throws IoTDBConnectionException { |
| session = |
| new Session( |
| sourceOptions.getHost(), |
| sourceOptions.getPort(), |
| sourceOptions.getUser(), |
| sourceOptions.getPassword()); |
| session.open(); |
| } |
| } |