/*
* Copyright 2016 Axibase Corporation or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* https://www.axibase.com/atsd/axibase-apache-2.0.pdf
*
* or in the "license" file accompanying this file. This file 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 com.axibase.tsd.client;
import com.axibase.tsd.model.system.MarkerState;
import com.axibase.tsd.network.MarkerCommand;
import com.axibase.tsd.network.PlainCommand;
import com.axibase.tsd.query.Query;
import com.axibase.tsd.query.QueryPart;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.*;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
public class DefaultStreamingManager implements StreamingManager {
private static final Logger log = LoggerFactory.getLogger(DefaultStreamingManager.class);
public static final String CHECK = "check";
private static final int DEFAULT_CHECK_PERIOD_MS = 5000;
private long checkPeriodMillis = DEFAULT_CHECK_PERIOD_MS;
private PlainStreamingSender plainSender = null;
private final AtomicLong lastPingTime = new AtomicLong(0);
private final AtomicReference<String> marker = new AtomicReference<String>();
private boolean lastPingResult = false;
private final List<String> saved = new ArrayList<String>();
private final HttpClientManager httpClientManager;
private Future<?> senderFuture;
private ExecutorService checkExecutor;
private ExecutorService senderExecutor;
private ReadWriteLock senderLock = new ReentrantReadWriteLock();
public DefaultStreamingManager(HttpClientManager httpClientManager) {
if (httpClientManager == null) {
throw new IllegalArgumentException("httpClientManager is null");
}
this.httpClientManager = httpClientManager;
checkExecutor = Executors.newSingleThreadExecutor();
senderExecutor = Executors.newSingleThreadExecutor();
}
@Override
public void setCheckPeriodMillis(long checkPeriodMillis) {
this.checkPeriodMillis = checkPeriodMillis;
}
@Override
public void close() {
log.info("Close streaming manager");
PlainStreamingSender sender = plainSender;
if (sender != null) {
sender.close();
}
checkExecutor.shutdown();
senderExecutor.shutdown();
}
@Override
public void send(PlainCommand plainCommand) {
if (!lastPingResult) {
throw new IllegalStateException("Last check was bad, call canSend() method before command sending");
}
Lock readLock = senderLock.readLock();
readLock.lock();
try {
PlainStreamingSender sender = plainSender;
if (sender == null) {
throw new IllegalStateException("Sender is null");
} else if (!sender.isWorking()) {
throw new IllegalStateException("Sender is in the wrong state");
}
sender.send(plainCommand);
} finally {
readLock.unlock();
}
}
@Override
public boolean canSend() {
for (; ; ) {
long last = lastPingTime.get();
long current = System.currentTimeMillis();
if (current - last > checkPeriodMillis) {
if (lastPingTime.compareAndSet(last, current)) {
checkExecutor.execute(new Runnable() {
@Override
public void run() {
try {
boolean beforeLastResult = lastPingResult;
prepareAndCheckSender();
if (beforeLastResult && lastPingResult) {
saved.clear();
}
} catch (Throwable e) {
log.error("Could not prepare sender: ", e);
}
}
});
break;
}
} else {
break;
}
}
Lock readLock = senderLock.readLock();
readLock.lock();
try {
return lastPingResult && plainSender != null && plainSender.isWorking();
} finally {
readLock.unlock();
}
}
private void prepareAndCheckSender() {
if (plainSender == null || plainSender.isClosed()) {
Lock writeLock = senderLock.writeLock();
writeLock.lock();
try {
if (plainSender == null || plainSender.isClosed()) {
PlainStreamingSender newSender = new PlainStreamingSender(httpClientManager.getClientConfiguration(), plainSender);
if (plainSender != null) {
log.info("Prepare new sender, close old");
plainSender.close();
}
if (senderFuture != null) {
senderFuture.cancel(true);
}
senderFuture = senderExecutor.submit(newSender);
plainSender = newSender;
}
} finally {
writeLock.unlock();
}
}
lastPingResult = check();
if (lastPingResult) {
compareAndSendNewMarker(marker.get());
}
}
private boolean check() {
if (httpClientManager.getClientConfiguration().isSkipStreamingControl()) {
return true;
}
boolean needClosing = false;
Lock readLock = senderLock.readLock();
readLock.lock();
try {
if (plainSender != null) {
Map<String, List<String>> markerToMessages = plainSender.getMarkerToMessages();
int size = markerToMessages.size();
if (size <= 2) {
// just check
MarkerState markerState = askMarkerState(CHECK);
boolean checkResult = markerState != null && CHECK.equals(markerState.getMarker());
if (!checkResult) {
log.warn("Bad check result, close sender");
needClosing = true;
}
return checkResult;
}
int i = 0;
for (Iterator<Map.Entry<String, List<String>>> iterator = markerToMessages.entrySet().iterator();
iterator.hasNext() && i < size - 2; i++) {
Map.Entry<String, List<String>> markerAndCommands = iterator.next();
String checkedMarker = markerAndCommands.getKey();
MarkerState markerState = askMarkerState(checkedMarker);
List<String> commands = markerAndCommands.getValue();
if (markerState != null && markerState.getCount() != null) {
if (markerState.getCount() > commands.size()) {
log.warn("Server received more ({}) commands then client sent ({}), marker: {}",
markerState.getCount(), commands.size(), checkedMarker);
} else if (markerState.getCount() < commands.size()) {
log.error("Server received less ({}) commands then client sent ({}), marker: {}",
markerState.getCount(), commands.size(), checkedMarker);
saved.addAll(commands);
} else {
log.debug("Server received same command count ({}) that client sent, marker: {}",
commands.size(), checkedMarker);
}
iterator.remove();
} else {
log.warn("Could not get command count for marker {}", marker);
saved.addAll(commands);
iterator.remove();
}
}
if (saved.isEmpty()) {
return true;
} else {
for (Iterator<Map.Entry<String, List<String>>> iterator = markerToMessages.entrySet().iterator();
iterator.hasNext(); ) {
Map.Entry<String, List<String>> markerAndCommands = iterator.next();
List<String> commands = markerAndCommands.getValue();
saved.addAll(commands);
iterator.remove();
}
log.warn("Save {} commands, broken sender will be closed", saved.size());
needClosing = true;
return false;
}
} else {
log.warn("Sender is null");
return false;
}
} catch (Throwable e) {
log.warn("Ping error: ", e);
return false;
} finally {
readLock.unlock();
if (needClosing) {
Lock writeLock = senderLock.writeLock();
writeLock.lock();
try {
plainSender.close();
} finally {
writeLock.unlock();
}
}
}
}
private MarkerState askMarkerState(String marker) {
MarkerState markerState = null;
try {
QueryPart<MarkerState> markersPath = new Query<MarkerState>("command").path("marker");
QueryPart<MarkerState> query = markersPath.param("v", marker);
markerState = httpClientManager.requestData(MarkerState.class, query, null);
log.debug("From server {} received the following state of marker ({}): {}",
httpClientManager.getClientConfiguration().getDataUrl(), marker, markerState);
} catch (Throwable e) {
log.error("Error while checking marker count: ", e);
}
return markerState;
}
private void compareAndSendNewMarker(String current) {
log.debug("Send merker: {}", current);
if (httpClientManager.getClientConfiguration().isSkipStreamingControl()) {
return;
}
MarkerCommand markerCommand = new MarkerCommand();
final String newMarker = markerCommand.getMarker();
if (marker.compareAndSet(current, newMarker)) {
Lock readLock = senderLock.readLock();
readLock.lock();
try {
if (plainSender == null) {
throw new IllegalStateException("Sender is null");
} else if (!plainSender.isWorking()) {
throw new IllegalStateException("Sender is incorrect");
} else {
plainSender.send(markerCommand);
}
} finally {
readLock.unlock();
}
} else {
log.warn("Current marker:{} is already replaced by another marker:", current, marker.get());
}
}
@Override
public List<String> removeSavedPlainCommands() {
if (saved.isEmpty()) {
return Collections.emptyList();
}
synchronized (saved) {
List<String> result = new ArrayList<String>(saved);
saved.removeAll(result);
if (result.size() > 0) {
log.info("{} commands are removed from saved list", result.size());
}
return result;
}
}
}