/*
* 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
*
* 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.streams.moreover;
import org.apache.streams.config.ComponentConfigurator;
import org.apache.streams.config.StreamsConfiguration;
import org.apache.streams.config.StreamsConfigurator;
import org.apache.streams.core.StreamsDatum;
import org.apache.streams.core.StreamsProvider;
import org.apache.streams.core.StreamsResultSet;
import org.apache.streams.jackson.StreamsJacksonMapper;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.google.common.base.Preconditions;
import com.google.common.collect.Iterators;
import com.google.common.util.concurrent.Uninterruptibles;
import com.typesafe.config.Config;
import com.typesafe.config.ConfigFactory;
import com.typesafe.config.ConfigParseOptions;
import org.joda.time.DateTime;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.PrintStream;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
/**
* Streams Provider for the Moreover Metabase API.
*/
public class MoreoverProvider implements StreamsProvider {
public static final String STREAMS_ID = "MoreoverProvider";
private static final Logger LOGGER = LoggerFactory.getLogger(MoreoverProvider.class);
protected volatile Queue<StreamsDatum> providerQueue = new ConcurrentLinkedQueue<>();
private List<MoreoverKeyData> keys;
private MoreoverConfiguration config;
private ExecutorService executor;
/**
* MoreoverProvider constructor.
* @param moreoverConfiguration MoreoverConfiguration
*/
public MoreoverProvider(MoreoverConfiguration moreoverConfiguration) {
this.config = moreoverConfiguration;
this.keys = new ArrayList<>();
for ( MoreoverKeyData apiKey : config.getApiKeys()) {
this.keys.add(apiKey);
}
}
@Override
public String getId() {
return STREAMS_ID;
}
@Override
public void startStream() {
for (MoreoverKeyData key : keys) {
MoreoverProviderTask task = new MoreoverProviderTask(key.getId(), key.getKey(), this.providerQueue, key.getStartingSequence());
executor.submit(new Thread(task));
LOGGER.info("Started producer for {}", key.getKey());
}
}
@Override
public synchronized StreamsResultSet readCurrent() {
LOGGER.debug("readCurrent: {}", providerQueue.size());
Collection<StreamsDatum> currentIterator = new ArrayList<>();
Iterators.addAll(currentIterator, providerQueue.iterator());
StreamsResultSet current = new StreamsResultSet(new ConcurrentLinkedQueue<>(currentIterator));
providerQueue.clear();
return current;
}
@Override
public StreamsResultSet readNew(BigInteger sequence) {
return null;
}
@Override
public StreamsResultSet readRange(DateTime start, DateTime end) {
return null;
}
@Override
public boolean isRunning() {
return !executor.isShutdown() && !executor.isTerminated();
}
@Override
public void prepare(Object configurationObject) {
LOGGER.debug("Prepare");
executor = Executors.newSingleThreadExecutor();
}
@Override
public void cleanUp() {
}
/**
* To use from command line:
*
* <p/>
* Supply configuration similar to src/test/resources/rss.conf
*
* <p/>
* Launch using:
*
* <p/>
* mvn exec:java -Dexec.mainClass=org.apache.streams.moreover.MoreoverProvider -Dexec.args="rss.conf articles.json"
*
* @param args args
* @throws Exception Exception
*/
public static void main(String[] args) throws Exception {
Preconditions.checkArgument(args.length >= 2);
String configfile = args[0];
String outfile = args[1];
Config reference = ConfigFactory.load();
File file = new File(configfile);
assert (file.exists());
Config testResourceConfig = ConfigFactory.parseFileAnySyntax(file, ConfigParseOptions.defaults().setAllowMissing(false));
Config typesafe = testResourceConfig.withFallback(reference).resolve();
StreamsConfiguration streamsConfiguration = StreamsConfigurator.detectConfiguration(typesafe);
MoreoverConfiguration config = new ComponentConfigurator<>(MoreoverConfiguration.class).detectConfiguration(typesafe, "rss");
MoreoverProvider provider = new MoreoverProvider(config);
ObjectMapper mapper = StreamsJacksonMapper.getInstance();
PrintStream outStream = new PrintStream(new BufferedOutputStream(new FileOutputStream(outfile)));
provider.prepare(config);
provider.startStream();
do {
Uninterruptibles.sleepUninterruptibly(streamsConfiguration.getBatchFrequencyMs(), TimeUnit.MILLISECONDS);
for (StreamsDatum datum : provider.readCurrent()) {
String json;
try {
json = mapper.writeValueAsString(datum.getDocument());
outStream.println(json);
} catch (JsonProcessingException ex) {
System.err.println(ex.getMessage());
}
}
}
while ( provider.isRunning() );
provider.cleanUp();
outStream.flush();
}
}