| /** |
| * 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.apex.malhar.lib.util; |
| |
| import java.io.IOException; |
| import java.io.Serializable; |
| import java.util.List; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.datatorrent.api.Attribute.AttributeMap; |
| import com.datatorrent.api.Context.DAGContext; |
| import com.datatorrent.api.StorageAgent; |
| |
| /** |
| * Abstract implementation of {@link ApplicationAwareStorageAgent} which can be |
| * configured be KeyValue store witch implementation of {@link StorageAgentKeyValueStore} |
| * |
| * NOTE - this should be picked from APEX-CORE once below feature is release |
| * https://issues.apache.org/jira/browse/APEXCORE-283 |
| * |
| * @param <S> |
| * Store implementation |
| * |
| * @since 3.4.0 |
| */ |
| public abstract class AbstractKeyValueStorageAgent<S extends StorageAgentKeyValueStore> |
| implements StorageAgent.ApplicationAwareStorageAgent, Serializable |
| { |
| |
| protected S store; |
| protected String applicationId; |
| public static final String CHECKPOINT_KEY_SEPARATOR = "-"; |
| |
| /** |
| * Gets the store |
| * |
| * @return the store |
| */ |
| public S getStore() |
| { |
| return store; |
| } |
| |
| /** |
| * Sets the store |
| * |
| * @param store |
| */ |
| public void setStore(S store) |
| { |
| this.store = store; |
| } |
| |
| /** |
| * Return yarn application id of running application |
| * |
| * @return |
| */ |
| public String getApplicationId() |
| { |
| return applicationId; |
| } |
| |
| /** |
| * Set yarn application id |
| * |
| * @param applicationId |
| */ |
| public void setApplicationId(String applicationId) |
| { |
| this.applicationId = applicationId; |
| } |
| |
| /** |
| * Generates key from operator id and window id to store unique operator |
| * checkpoints |
| * |
| * @param operatorId |
| * @param windowId |
| * @return unique key for store |
| */ |
| public static String generateKey(int operatorId, long windowId) |
| { |
| return String.valueOf(operatorId) + CHECKPOINT_KEY_SEPARATOR + String.valueOf(windowId); |
| } |
| |
| /** |
| * Stores the given operator object in configured store |
| * |
| * @param object |
| * Operator object to store |
| * @param operatorId |
| * of operator |
| * @param windowId |
| * window id of operator to checkpoint |
| * |
| */ |
| @Override |
| public void save(Object object, int operatorId, long windowId) throws IOException |
| { |
| |
| try { |
| store(generateKey(operatorId, windowId), object); |
| logger.debug("saved check point object key {} region {}", generateKey(operatorId, windowId), applicationId); |
| } catch (Exception ex) { |
| throw new RuntimeException(ex); |
| } |
| } |
| |
| private synchronized void store(String checkpointKey, Object operator) throws IOException |
| { |
| if (!getStore().isConnected()) { |
| getStore().connect(); |
| } |
| getStore().put(checkpointKey, operator); |
| } |
| |
| /** |
| * Retrieves the operator object for given operator & window from configured |
| * store |
| * |
| * @param operatorId |
| * of operator |
| * @param windowId |
| * window id of operator to checkpoint |
| */ |
| @Override |
| public Object load(int operatorId, long windowId) |
| { |
| Object obj = null; |
| try { |
| obj = retrieve(generateKey(operatorId, windowId)); |
| logger.debug("retrieved object from store key {} region {} ", generateKey(operatorId, windowId), applicationId); |
| } catch (Exception ex) { |
| throw new RuntimeException(ex); |
| } |
| |
| return obj; |
| } |
| |
| private synchronized Object retrieve(String checkpointKey) throws IOException |
| { |
| if (!getStore().isConnected()) { |
| getStore().connect(); |
| } |
| |
| return getStore().get(checkpointKey); |
| } |
| |
| /** |
| * Removes stored operator object for given operatorId & windowId from store |
| * |
| */ |
| @Override |
| public void delete(int operatorId, long windowId) throws IOException |
| { |
| |
| if (!getStore().isConnected()) { |
| getStore().connect(); |
| } |
| |
| try { |
| getStore().remove(generateKey(operatorId, windowId)); |
| logger.debug("deleted object from store key {} region {}", generateKey(operatorId, windowId)); |
| } catch (Exception ex) { |
| throw new RuntimeException(ex); |
| } |
| |
| } |
| |
| /** |
| * Returns list window id for given operator id for which operator objects are |
| * stored but not removed |
| * |
| */ |
| @Override |
| public long[] getWindowIds(int operatorId) throws IOException |
| { |
| if (!getStore().isConnected()) { |
| getStore().connect(); |
| } |
| |
| List<String> keys = getStore().getKeys(operatorId); |
| if (keys.size() > 0) { |
| long[] windowsIds = new long[keys.size()]; |
| int count = 0; |
| for (String key : keys) { |
| windowsIds[count] = extractwindowId(key); |
| count++; |
| } |
| return windowsIds; |
| } else { |
| return new long[0]; |
| } |
| } |
| |
| public static long extractwindowId(String checkpointKey) |
| { |
| String[] parts = checkpointKey.split(CHECKPOINT_KEY_SEPARATOR); |
| return Long.parseLong(parts[1]); |
| } |
| |
| /** |
| * Saves the yarn application id which can be used by create application |
| * specific table/region in KeyValue sore. |
| */ |
| @Override |
| public void setApplicationAttributes(AttributeMap map) |
| { |
| this.applicationId = map.get(DAGContext.APPLICATION_ID); |
| getStore().setTableName(applicationId); |
| } |
| |
| private static final long serialVersionUID = 7065320156997171116L; |
| private static final Logger logger = LoggerFactory.getLogger(AbstractKeyValueStorageAgent.class); |
| |
| } |