/**
* This file is part of Graylog.
*
* Graylog is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Graylog is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Graylog. If not, see <http://www.gnu.org/licenses/>.
*/
package org.graylog2.indexer.rotation.strategies;
import com.google.common.base.MoreObjects;
import org.graylog2.audit.AuditEventSender;
import org.graylog2.indexer.IndexSet;
import org.graylog2.indexer.indexset.IndexSetConfig;
import org.graylog2.indexer.indices.Indices;
import org.graylog2.plugin.Tools;
import org.graylog2.plugin.indexer.rotation.RotationStrategyConfig;
import org.graylog2.plugin.system.NodeId;
import org.joda.time.DateTime;
import org.joda.time.DateTimeField;
import org.joda.time.DateTimeFieldType;
import org.joda.time.DateTimeZone;
import org.joda.time.Period;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.annotation.Nullable;
import javax.inject.Inject;
import javax.inject.Singleton;
import java.text.MessageFormat;
import java.util.Locale;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import static com.google.common.base.Preconditions.checkState;
import static com.google.common.base.Strings.isNullOrEmpty;
import static java.util.Objects.requireNonNull;
import static org.joda.time.DateTimeFieldType.dayOfMonth;
import static org.joda.time.DateTimeFieldType.hourOfDay;
import static org.joda.time.DateTimeFieldType.minuteOfHour;
import static org.joda.time.DateTimeFieldType.monthOfYear;
import static org.joda.time.DateTimeFieldType.secondOfMinute;
import static org.joda.time.DateTimeFieldType.weekOfWeekyear;
import static org.joda.time.DateTimeFieldType.year;
@Singleton
public class TimeBasedRotationStrategy extends AbstractRotationStrategy {
private static final Logger log = LoggerFactory.getLogger(TimeBasedRotationStrategy.class);
private final Indices indices;
private Map<String, DateTime> lastRotation;
private Map<String, DateTime> anchor;
@Inject
public TimeBasedRotationStrategy(Indices indices, NodeId nodeId,
AuditEventSender auditEventSender) {
super(auditEventSender, nodeId);
this.anchor = new ConcurrentHashMap<>();
this.lastRotation = new ConcurrentHashMap<>();
this.indices = requireNonNull(indices, "indices must not be null");
}
@Override
public Class<? extends RotationStrategyConfig> configurationClass() {
return TimeBasedRotationStrategyConfig.class;
}
@Override
public RotationStrategyConfig defaultConfiguration() {
return TimeBasedRotationStrategyConfig.createDefault();
}
/**
* Determines the starting point ("anchor") for a period.
*
* To produce repeatable rotation points in time, the period is "snapped" to a "grid" of time.
* For example, an hourly index rotation would be anchored to the last full hour, instead of happening at whatever minute
* the first rotation was started.
*
* This "snapping" is done accordingly with the other parts of a period.
*
* For highly irregular periods (those that do not have a small zero component)
*
* @param period the rotation period
* @return the anchor DateTime to calculate rotation periods from
*/
static DateTime determineRotationPeriodAnchor(@Nullable DateTime lastAnchor, Period period) {
final Period normalized = period.normalizedStandard();
int years = normalized.getYears();
int months = normalized.getMonths();
int weeks = normalized.getWeeks();
int days = normalized.getDays();
int hours = normalized.getHours();
int minutes = normalized.getMinutes();
int seconds = normalized.getSeconds();
if (years == 0 && months == 0 && weeks == 0 && days == 0 && hours == 0 && minutes == 0 && seconds == 0) {
throw new IllegalArgumentException("Invalid rotation period specified");
}
// find the largest non-zero stride in the period. that's our anchor type. statement order matters here!
DateTimeFieldType largestStrideType = null;
if (seconds > 0) largestStrideType = secondOfMinute();
if (minutes > 0) largestStrideType = minuteOfHour();
if (hours > 0) largestStrideType = hourOfDay();
if (days > 0) largestStrideType = dayOfMonth();
if (weeks > 0) largestStrideType = weekOfWeekyear();
if (months > 0) largestStrideType = monthOfYear();
if (years > 0) largestStrideType = year();
if (largestStrideType == null) {
throw new IllegalArgumentException("Could not determine rotation stride length.");
}
final DateTime anchorTime = MoreObjects.firstNonNull(lastAnchor, Tools.nowUTC());
final DateTimeField field = largestStrideType.getField(anchorTime.getChronology());
// use normalized here to make sure we actually have the largestStride type available! see https://github.com/Graylog2/graylog2-server/issues/836
int periodValue = normalized.get(largestStrideType.getDurationType());
final long fieldValue = field.roundFloor(anchorTime.getMillis());
final int fieldValueInUnit = field.get(fieldValue);
if (periodValue == 0) {
// https://github.com/Graylog2/graylog2-server/issues/836
log.warn("Determining stride length failed because of a 0 period. Defaulting back to 1 period to avoid crashing, but this is a bug!");
periodValue = 1;
}
final long difference = fieldValueInUnit % periodValue;
final long newValue = field.add(fieldValue, -1 * difference);
return new DateTime(newValue, DateTimeZone.UTC);
}
@Nullable
@Override
protected Result shouldRotate(String index, IndexSet indexSet) {
final IndexSetConfig indexSetConfig = requireNonNull(indexSet.getConfig(), "Index set configuration must not be null");
final String indexSetId = indexSetConfig.id();
checkState(!isNullOrEmpty(index), "Index name must not be null or empty");
checkState(!isNullOrEmpty(indexSetId), "Index set ID must not be null or empty");
checkState(indexSetConfig.rotationStrategy() instanceof TimeBasedRotationStrategyConfig,
"Invalid rotation strategy config <" + indexSetConfig.rotationStrategy().getClass().getCanonicalName() + "> for index set <" + indexSetId + ">");
final TimeBasedRotationStrategyConfig config = (TimeBasedRotationStrategyConfig) indexSetConfig.rotationStrategy();
final Period rotationPeriod = config.rotationPeriod().normalizedStandard();
final DateTime now = Tools.nowUTC();
// when first started, we might not know the last rotation time, look up the creation time of the index instead.
if (!lastRotation.containsKey(indexSetId)) {
indices.indexCreationDate(index).ifPresent(creationDate -> {
final DateTime currentAnchor = determineRotationPeriodAnchor(creationDate, rotationPeriod);
anchor.put(indexSetId, currentAnchor);
lastRotation.put(indexSetId, creationDate);
});
// still not able to figure out the last rotation time, we'll rotate forcibly
if (!lastRotation.containsKey(indexSetId)) {
return new SimpleResult(true, "No known previous rotation time, forcing index rotation now.");
}
}
final DateTime currentAnchor = anchor.get(indexSetId);
final DateTime nextRotation = currentAnchor.plus(rotationPeriod);
if (nextRotation.isAfter(now)) {
final String message = new MessageFormat("Next rotation at {0}", Locale.ENGLISH)
.format(new Object[]{nextRotation});
return new SimpleResult(false, message);
}
// determine new anchor (push it to within less then one period before now) in case we missed one or more periods
DateTime tmpAnchor;
int multiplicator = 0;
do {
tmpAnchor = currentAnchor.withPeriodAdded(rotationPeriod, ++multiplicator);
} while (tmpAnchor.isBefore(now));
final DateTime nextAnchor = currentAnchor.withPeriodAdded(rotationPeriod, multiplicator - 1);
anchor.put(indexSetId, nextAnchor);
lastRotation.put(indexSetId, now);
final String message = new MessageFormat("Rotation period {0} elapsed, next rotation at {1}", Locale.ENGLISH)
.format(new Object[]{now, nextAnchor});
return new SimpleResult(true, message);
}
static class SimpleResult implements AbstractRotationStrategy.Result {
private final String message;
private final boolean rotate;
SimpleResult(boolean rotate, String message) {
this.message = message;
this.rotate = rotate;
log.debug("{} because of: {}", rotate ? "Rotating" : "Not rotating", message);
}
@Override
public String getDescription() {
return message;
}
@Override
public boolean shouldRotate() {
return rotate;
}
}
}