| /* |
| * 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.samza.coordinator.stream; |
| |
| import joptsimple.OptionSet; |
| import org.apache.samza.config.Config; |
| import org.apache.samza.coordinator.stream.messages.SetConfig; |
| import org.apache.samza.execution.JobPlanner; |
| import org.apache.samza.metrics.MetricsRegistryMap; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| |
| /** |
| * This class writes control messages to the CoordinatorStream. |
| * To use this class it, first, it should be initialized by the start() method, |
| * and then use the sendMessage() function to send all the control messages needed. |
| * Finally, the stop() method should be called. |
| * The control messages are in the format of a (type, key, value) where: |
| * type: defines the kind of message of the control message from the set {set-config}. |
| * key: defines a key to associate with the value. This can be null as well for messages with no value |
| * value: defines the value being sent along with the message. This can be null as well for messages with no value. |
| */ |
| public class CoordinatorStreamWriter { |
| |
| private static final Logger log = LoggerFactory.getLogger(CoordinatorStreamWriter.class); |
| public final static String SOURCE = "coordinator-stream-writer"; |
| public static final String SET_CONFIG_TYPE = SetConfig.TYPE; |
| |
| private CoordinatorStreamSystemProducer coordinatorStreamSystemProducer; |
| |
| |
| public CoordinatorStreamWriter(Config config) { |
| coordinatorStreamSystemProducer = new CoordinatorStreamSystemProducer(config, new MetricsRegistryMap()); |
| } |
| |
| /** |
| * This method initializes the writer by starting a coordinator stream producer. |
| */ |
| public void start() { |
| coordinatorStreamSystemProducer.register(CoordinatorStreamWriter.SOURCE); |
| coordinatorStreamSystemProducer.start(); |
| log.info("Started coordinator stream writer."); |
| } |
| |
| /** |
| * This method stops the writer and closes the coordinator stream producer |
| */ |
| public void stop() { |
| log.info("Stopping the coordinator stream producer."); |
| coordinatorStreamSystemProducer.stop(); |
| } |
| |
| /** |
| * This method sends a message to the coordinator stream. This creates a message containing (type,key,value). |
| * For example if you want to set the number of yarn containers to 3, you would use |
| * ("set-config", "yarn.container.count", "3"). |
| * |
| * @param type defines the kind of message of the control message from the set {"set-config"}. |
| * @param key defines a key to associate with the value. This can be null for messages with no key or value. |
| * @param value defines the value being sent along with the message. This can be null for messages with no value. |
| */ |
| public void sendMessage(String type, String key, String value) { |
| //TODO: validate keys and values |
| if (type.equals(SET_CONFIG_TYPE)) { |
| sendSetConfigMessage(key, value); |
| } else { |
| throw new IllegalArgumentException("Type is invalid. The possible values are {" + SET_CONFIG_TYPE + "}"); |
| } |
| } |
| |
| /** |
| * This method sends message of type "set-config" to the coordinator stream |
| * |
| * @param key defines the name of the configuration being set. For example, for setting the number of yarn containers, |
| * the key is "yarn.container.count" |
| * @param value defines the value associated with the key. For example, if the key is "yarn.container.count" the value |
| * is the new number of containers. |
| */ |
| private void sendSetConfigMessage(String key, String value) { |
| log.info("sent SetConfig message with key = " + key + " and value = " + value); |
| coordinatorStreamSystemProducer.send(new SetConfig(CoordinatorStreamWriter.SOURCE, key, value)); |
| } |
| |
| /** |
| * Main function for using the CoordinatorStreamWriter. The main function starts a CoordinatorStreamWriter |
| * and sends control messages. |
| * To run the code use the following command: |
| * {path to samza deployment}/samza/bin/run-coordinator-stream-writer.sh --config job.config.loader.factory={config-loader-factory} --config job.config.loader.properties{properties needed for config loader to load config} --type={type of the message} --key={[optional] key of the message} --value={[optional] value of the message} |
| * |
| * @param args input arguments for running the writer. These arguments are: |
| * "type" = type of the message being written |
| * "key" = [optional] key of the message being written |
| * "value" = [optional] value of the message being written |
| */ |
| public static void main(String[] args) { |
| CoordinatorStreamWriterCommandLine cmdline = new CoordinatorStreamWriterCommandLine(); |
| OptionSet options = cmdline.parser().parse(args); |
| Config userConfig = cmdline.loadConfig(options); |
| Config generatedConfig = JobPlanner.generateSingleJobConfig(userConfig); |
| String type = cmdline.loadType(options); |
| String key = cmdline.loadKey(options); |
| String value = cmdline.loadValue(options); |
| |
| CoordinatorStreamWriter writer = new CoordinatorStreamWriter(generatedConfig); |
| writer.start(); |
| writer.sendMessage(type, key, value); |
| writer.stop(); |
| } |
| |
| } |
| |