/*
* 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.streams.sysomos.provider;
import org.apache.streams.core.StreamsDatum;
import com.sysomos.xml.BeatApi;
import org.joda.time.DateTime;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Provides a {@link java.lang.Runnable} query mechanism for grabbing documents from the Sysomos API
*/
public class SysomosHeartbeatStream implements Runnable {
private enum OperatingMode { DATE, DOC_MATCH }
private static final Logger LOGGER = LoggerFactory.getLogger(SysomosHeartbeatStream.class);
private final SysomosProvider provider;
private final SysomosClient client;
private final String heartbeatId;
private final long maxApiBatch;
private final long minLatency;
private final OperatingMode mode;
private String lastId;
private DateTime beforeTime;
private DateTime afterTime;
private DateTime lastRunTime;
private int offsetCount = 0;
private boolean enabled = true;
public SysomosHeartbeatStream(SysomosProvider provider, String heartbeatId) {
this(provider, heartbeatId, null, DateTime.now());
}
/**
* SysomosHeartbeatStream constructor.
* @param provider SysomosProvider
* @param heartbeatId heartbeatId
* @param beforeTime DateTime
* @param afterTime DateTime
*/
public SysomosHeartbeatStream(SysomosProvider provider, String heartbeatId, DateTime beforeTime, DateTime afterTime) {
this(provider, heartbeatId, OperatingMode.DATE);
this.beforeTime = beforeTime;
this.afterTime = afterTime;
}
/**
* SysomosHeartbeatStream constructor.
* @param provider SysomosProvider
* @param heartbeatId heartbeatId
* @param documentId last documentId
*/
public SysomosHeartbeatStream(SysomosProvider provider, String heartbeatId, String documentId) {
this(provider, heartbeatId, OperatingMode.DOC_MATCH);
this.lastId = documentId;
}
/**
* SysomosHeartbeatStream constructor.
* @param provider SysomosProvider
* @param heartbeatId heartbeatId
* @param mode OperatingMode
*/
public SysomosHeartbeatStream(SysomosProvider provider, String heartbeatId, OperatingMode mode) {
this.provider = provider;
this.heartbeatId = heartbeatId;
this.client = provider.getClient();
this.maxApiBatch = provider.getMaxApiBatch();
this.minLatency = provider.getMinLatency();
this.mode = mode;
}
@Override
public void run() {
try {
executeRun();
} catch (Exception ex) {
LOGGER.error("Error executing heartbeat stream", ex);
shutdown();
}
}
protected void executeRun() {
QueryResult result;
String mostCurrentId = null;
int totalDocCount = 0;
lastRunTime = DateTime.now();
//Iff we are trying to get to a specific document ID, continue to query after minimum delay
do {
LOGGER.debug("Querying API to match last ID of {} or time range of {} - {}", lastId, afterTime, beforeTime);
result = queryApi();
totalDocCount += result.getResponseSize();
//Ensure that we are only assigning lastId to the latest ID, even if there is backfill query.
//Since offset is calcuated at the end of the run, if we detect the need to backfill, it will increment to 1
if (offsetCount == 1) {
mostCurrentId = result.getCurrentId();
}
updateOffset(result);
}
while (offsetCount > 0);
updateState(result, mostCurrentId, totalDocCount);
LOGGER.debug("Completed current execution with a final docID of {} or time of {}", lastId, afterTime);
}
protected void updateState(QueryResult result, String mostCurrentId, int totalDocCount) {
if (OperatingMode.DOC_MATCH.equals(mode)) {
//Set the last ID so that the next time we are executed we will continue to query only so long as we haven't
//found the specific ID
lastId = mostCurrentId == null ? result.getCurrentId() : mostCurrentId;
} else {
//If we didn't see any docs, there might be a lag on the Sysomos side. Retry.
afterTime = totalDocCount == 0 ? afterTime : lastRunTime;
}
if (SysomosProvider.Mode.BACKFILL_AND_TERMINATE.equals(provider.getMode())) {
shutdown();
LOGGER.info("Completed backfill to {} for heartbeat {}", OperatingMode.DOC_MATCH.equals(mode) ? lastId : afterTime, heartbeatId);
}
}
protected void updateOffset(QueryResult result) {
if (OperatingMode.DOC_MATCH.equals(mode)) {
//Reset the offset iff we have found a match or this is the first execution
offsetCount = lastId == null || result.isMatchedLastId() ? 0 : offsetCount + 1;
} else {
offsetCount = result.getResponseSize() == 0 ? 0 : offsetCount + 1;
}
if (offsetCount > 0) {
sleep();
}
}
protected void sleep() {
try {
Thread.sleep(this.minLatency);
} catch (InterruptedException ex) {
LOGGER.warn("Thread interrupted while sleeping minimum delay", ex);
shutdown();
}
}
protected QueryResult queryApi() {
BeatApi.BeatResponse response = executeApiRequest();
String currentId = null;
boolean matched = false;
int responseSize = 0;
if (response != null) {
for (BeatApi.BeatResponse.Beat beat : response.getBeat()) {
String docId = beat.getDocid();
//We get documents in descending time order. This will set the id to the latest document
if (currentId == null) {
currentId = docId;
}
//We only want to process documents that we know we have not seen before
if (lastId != null && lastId.equals(docId)) {
matched = true;
break;
}
StreamsDatum item = new StreamsDatum(beat, docId);
item.getMetadata().put("heartbeat", this.heartbeatId);
this.provider.enqueueItem(item);
}
responseSize = response.getCount();
}
return new QueryResult(matched, currentId, responseSize);
}
protected BeatApi.BeatResponse executeApiRequest() {
BeatApi.BeatResponse response = null;
try {
if (enabled) {
RequestBuilder requestBuilder = this.client.createRequestBuilder()
.setHeartBeatId(heartbeatId)
.setOffset(offsetCount * maxApiBatch)
.setReturnSetSize(maxApiBatch);
if (beforeTime != null) {
requestBuilder.setAddedBeforeDate(beforeTime);
}
if (afterTime != null) {
requestBuilder.setAddedAfterDate(afterTime);
}
response = requestBuilder.execute();
LOGGER.debug("Received {} results from API query", response.getCount());
}
} catch (Exception ex) {
LOGGER.warn("Error querying Sysomos API", ex);
}
return response;
}
protected void shutdown() {
provider.signalComplete(heartbeatId);
enabled = false;
}
protected class QueryResult {
private boolean matchedLastId;
private String currentId;
private int responseSize;
public QueryResult(boolean matchedLastId, String currentId, int responseSize) {
this.matchedLastId = matchedLastId;
this.currentId = currentId;
this.responseSize = responseSize;
}
public boolean isMatchedLastId() {
return matchedLastId;
}
public void setMatchedLastId(boolean matchedLastId) {
this.matchedLastId = matchedLastId;
}
public String getCurrentId() {
return currentId;
}
public void setCurrentId(String currentId) {
this.currentId = currentId;
}
public int getResponseSize() {
return responseSize;
}
public void setResponseSize(int responseSize) {
this.responseSize = responseSize;
}
}
}