/*
* 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.kafka.common.metrics;
import org.apache.kafka.common.MetricName;
import org.apache.kafka.common.metrics.CompoundStat.NamedMeasurable;
import org.apache.kafka.common.utils.Time;
import org.apache.kafka.common.utils.Utils;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Locale;
import java.util.Set;
import java.util.concurrent.TimeUnit;
/**
* A sensor applies a continuous sequence of numerical values to a set of associated metrics. For example a sensor on
* message size would record a sequence of message sizes using the {@link #record(double)} api and would maintain a set
* of metrics about request sizes such as the average or max.
*/
public final class Sensor {
private final Metrics registry;
private final String name;
private final Sensor[] parents;
private final List<Stat> stats;
private final List<KafkaMetric> metrics;
private final MetricConfig config;
private final Time time;
private volatile long lastRecordTime;
private final long inactiveSensorExpirationTimeMs;
public enum RecordingLevel {
INFO(0, "INFO"), DEBUG(1, "DEBUG");
private static final RecordingLevel[] ID_TO_TYPE;
private static final int MIN_RECORDING_LEVEL_KEY = 0;
public static final int MAX_RECORDING_LEVEL_KEY;
static {
int maxRL = -1;
for (RecordingLevel level : RecordingLevel.values()) {
maxRL = Math.max(maxRL, level.id);
}
RecordingLevel[] idToName = new RecordingLevel[maxRL + 1];
for (RecordingLevel level : RecordingLevel.values()) {
idToName[level.id] = level;
}
ID_TO_TYPE = idToName;
MAX_RECORDING_LEVEL_KEY = maxRL;
}
/** an english description of the api--this is for debugging and can change */
public final String name;
/** the permanent and immutable id of an API--this can't change ever */
public final short id;
RecordingLevel(int id, String name) {
this.id = (short) id;
this.name = name;
}
public static RecordingLevel forId(int id) {
if (id < MIN_RECORDING_LEVEL_KEY || id > MAX_RECORDING_LEVEL_KEY)
throw new IllegalArgumentException(String.format("Unexpected RecordLevel id `%s`, it should be between `%s` " +
"and `%s` (inclusive)", id, MIN_RECORDING_LEVEL_KEY, MAX_RECORDING_LEVEL_KEY));
return ID_TO_TYPE[id];
}
/** Case insensitive lookup by protocol name */
public static RecordingLevel forName(String name) {
return RecordingLevel.valueOf(name.toUpperCase(Locale.ROOT));
}
public boolean shouldRecord(final int configId) {
if (configId == DEBUG.id) {
return true;
} else {
return configId == this.id;
}
}
}
private final RecordingLevel recordingLevel;
Sensor(Metrics registry, String name, Sensor[] parents, MetricConfig config, Time time,
long inactiveSensorExpirationTimeSeconds, RecordingLevel recordingLevel) {
super();
this.registry = registry;
this.name = Utils.notNull(name);
this.parents = parents == null ? new Sensor[0] : parents;
this.metrics = new ArrayList<>();
this.stats = new ArrayList<>();
this.config = config;
this.time = time;
this.inactiveSensorExpirationTimeMs = TimeUnit.MILLISECONDS.convert(inactiveSensorExpirationTimeSeconds, TimeUnit.SECONDS);
this.lastRecordTime = time.milliseconds();
this.recordingLevel = recordingLevel;
checkForest(new HashSet<Sensor>());
}
/* Validate that this sensor doesn't end up referencing itself */
private void checkForest(Set<Sensor> sensors) {
if (!sensors.add(this))
throw new IllegalArgumentException("Circular dependency in sensors: " + name() + " is its own parent.");
for (Sensor parent : parents)
parent.checkForest(sensors);
}
/**
* The name this sensor is registered with. This name will be unique among all registered sensors.
*/
public String name() {
return this.name;
}
/**
* Record an occurrence, this is just short-hand for {@link #record(double) record(1.0)}
*/
public void record() {
if (shouldRecord()) {
record(1.0);
}
}
/**
* @return true if the sensor's record level indicates that the metric will be recorded, false otherwise
*/
public boolean shouldRecord() {
return this.recordingLevel.shouldRecord(config.recordLevel().id);
}
/**
* Record a value with this sensor
* @param value The value to record
* @throws QuotaViolationException if recording this value moves a metric beyond its configured maximum or minimum
* bound
*/
public void record(double value) {
if (shouldRecord()) {
record(value, time.milliseconds());
}
}
/**
* Record a value at a known time. This method is slightly faster than {@link #record(double)} since it will reuse
* the time stamp.
* @param value The value we are recording
* @param timeMs The current POSIX time in milliseconds
* @throws QuotaViolationException if recording this value moves a metric beyond its configured maximum or minimum
* bound
*/
public void record(double value, long timeMs) {
record(value, timeMs, true);
}
public void record(double value, long timeMs, boolean checkQuotas) {
if (shouldRecord()) {
this.lastRecordTime = timeMs;
synchronized (this) {
// increment all the stats
for (Stat stat : this.stats)
stat.record(config, value, timeMs);
if (checkQuotas)
checkQuotas(timeMs);
}
for (Sensor parent : parents)
parent.record(value, timeMs, checkQuotas);
}
}
/**
* Check if we have violated our quota for any metric that has a configured quota
*/
public void checkQuotas() {
checkQuotas(time.milliseconds());
}
public void checkQuotas(long timeMs) {
for (KafkaMetric metric : this.metrics) {
MetricConfig config = metric.config();
if (config != null) {
Quota quota = config.quota();
if (quota != null) {
double value = metric.value(timeMs);
if (!quota.acceptable(value)) {
throw new QuotaViolationException(metric.metricName(), value,
quota.bound());
}
}
}
}
}
/**
* Register a compound statistic with this sensor with no config override
*/
public void add(CompoundStat stat) {
add(stat, null);
}
/**
* Register a compound statistic with this sensor which yields multiple measurable quantities (like a histogram)
* @param stat The stat to register
* @param config The configuration for this stat. If null then the stat will use the default configuration for this
* sensor.
*/
public synchronized void add(CompoundStat stat, MetricConfig config) {
this.stats.add(Utils.notNull(stat));
for (NamedMeasurable m : stat.stats()) {
KafkaMetric metric = new KafkaMetric(this, m.name(), m.stat(), config == null ? this.config : config, time);
this.registry.registerMetric(metric);
this.metrics.add(metric);
}
}
/**
* Register a metric with this sensor
* @param metricName The name of the metric
* @param stat The statistic to keep
*/
public void add(MetricName metricName, MeasurableStat stat) {
add(metricName, stat, null);
}
/**
* Register a metric with this sensor
* @param metricName The name of the metric
* @param stat The statistic to keep
* @param config A special configuration for this metric. If null use the sensor default configuration.
*/
public synchronized void add(MetricName metricName, MeasurableStat stat, MetricConfig config) {
KafkaMetric metric = new KafkaMetric(new Object(),
Utils.notNull(metricName),
Utils.notNull(stat),
config == null ? this.config : config,
time);
this.registry.registerMetric(metric);
this.metrics.add(metric);
this.stats.add(stat);
}
/**
* Return true if the Sensor is eligible for removal due to inactivity.
* false otherwise
*/
public boolean hasExpired() {
return (time.milliseconds() - this.lastRecordTime) > this.inactiveSensorExpirationTimeMs;
}
synchronized List<KafkaMetric> metrics() {
return Collections.unmodifiableList(this.metrics);
}
}