io.opentelemetry.sdk.metrics.export.PeriodicMetricReader Maven / Gradle / Ivy
/*
* Copyright The OpenTelemetry Authors
* SPDX-License-Identifier: Apache-2.0
*/
package io.opentelemetry.sdk.metrics.export;
import io.opentelemetry.sdk.common.CompletableResultCode;
import io.opentelemetry.sdk.common.export.MemoryMode;
import io.opentelemetry.sdk.metrics.Aggregation;
import io.opentelemetry.sdk.metrics.InstrumentType;
import io.opentelemetry.sdk.metrics.SdkMeterProvider;
import io.opentelemetry.sdk.metrics.SdkMeterProviderBuilder;
import io.opentelemetry.sdk.metrics.data.AggregationTemporality;
import io.opentelemetry.sdk.metrics.data.MetricData;
import java.util.Collection;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.annotation.Nullable;
/**
* A {@link MetricReader} which wraps a {@link MetricExporter} and automatically reads and exports
* the metrics every export interval.
*
* Register with {@link SdkMeterProvider} via {@link
* SdkMeterProviderBuilder#registerMetricReader(MetricReader)}.
*
* @since 1.14.0
*/
public final class PeriodicMetricReader implements MetricReader {
private static final Logger logger = Logger.getLogger(PeriodicMetricReader.class.getName());
private final MetricExporter exporter;
private final long intervalNanos;
private final ScheduledExecutorService scheduler;
private final Scheduled scheduled;
private final Object lock = new Object();
private volatile CollectionRegistration collectionRegistration = CollectionRegistration.noop();
@Nullable private volatile ScheduledFuture scheduledFuture;
/**
* Returns a new {@link PeriodicMetricReader} which exports to the {@code exporter} once every
* minute.
*/
public static PeriodicMetricReader create(MetricExporter exporter) {
return builder(exporter).build();
}
/** Returns a new {@link PeriodicMetricReaderBuilder}. */
public static PeriodicMetricReaderBuilder builder(MetricExporter exporter) {
return new PeriodicMetricReaderBuilder(exporter);
}
PeriodicMetricReader(
MetricExporter exporter, long intervalNanos, ScheduledExecutorService scheduler) {
this.exporter = exporter;
this.intervalNanos = intervalNanos;
this.scheduler = scheduler;
this.scheduled = new Scheduled();
}
@Override
public AggregationTemporality getAggregationTemporality(InstrumentType instrumentType) {
return exporter.getAggregationTemporality(instrumentType);
}
@Override
public Aggregation getDefaultAggregation(InstrumentType instrumentType) {
return exporter.getDefaultAggregation(instrumentType);
}
@Override
public MemoryMode getMemoryMode() {
return exporter.getMemoryMode();
}
@Override
public CompletableResultCode forceFlush() {
return scheduled.doRun();
}
@Override
public CompletableResultCode shutdown() {
CompletableResultCode result = new CompletableResultCode();
ScheduledFuture scheduledFuture = this.scheduledFuture;
if (scheduledFuture != null) {
scheduledFuture.cancel(false);
}
scheduler.shutdown();
try {
scheduler.awaitTermination(5, TimeUnit.SECONDS);
CompletableResultCode flushResult = scheduled.doRun();
flushResult.join(5, TimeUnit.SECONDS);
} catch (InterruptedException e) {
// force a shutdown if the export hasn't finished.
scheduler.shutdownNow();
// reset the interrupted status
Thread.currentThread().interrupt();
} finally {
CompletableResultCode shutdownResult = scheduled.shutdown();
shutdownResult.whenComplete(
() -> {
if (!shutdownResult.isSuccess()) {
result.fail();
} else {
result.succeed();
}
});
}
return result;
}
@Override
public void register(CollectionRegistration collectionRegistration) {
this.collectionRegistration = collectionRegistration;
start();
}
@Override
public String toString() {
return "PeriodicMetricReader{"
+ "exporter="
+ exporter
+ ", intervalNanos="
+ intervalNanos
+ '}';
}
void start() {
synchronized (lock) {
if (scheduledFuture != null) {
return;
}
scheduledFuture =
scheduler.scheduleAtFixedRate(
scheduled, intervalNanos, intervalNanos, TimeUnit.NANOSECONDS);
}
}
private final class Scheduled implements Runnable {
private final AtomicBoolean exportAvailable = new AtomicBoolean(true);
private Scheduled() {}
@Override
public void run() {
// Ignore the CompletableResultCode from doRun() in order to keep run() asynchronous
doRun();
}
// Runs a collect + export cycle.
CompletableResultCode doRun() {
CompletableResultCode flushResult = new CompletableResultCode();
if (exportAvailable.compareAndSet(true, false)) {
try {
Collection metricData = collectionRegistration.collectAllMetrics();
if (metricData.isEmpty()) {
logger.log(Level.FINE, "No metric data to export - skipping export.");
flushResult.succeed();
exportAvailable.set(true);
} else {
CompletableResultCode result = exporter.export(metricData);
result.whenComplete(
() -> {
if (!result.isSuccess()) {
logger.log(Level.FINE, "Exporter failed");
}
flushResult.succeed();
exportAvailable.set(true);
});
}
} catch (Throwable t) {
exportAvailable.set(true);
logger.log(Level.WARNING, "Exporter threw an Exception", t);
flushResult.fail();
}
} else {
logger.log(Level.FINE, "Exporter busy. Dropping metrics.");
flushResult.fail();
}
return flushResult;
}
CompletableResultCode shutdown() {
return exporter.shutdown();
}
}
}