/**
* Copyright 2012 Netflix, Inc.
*
* Licensed 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 com.netflix.hystrix.contrib.metrics.eventstream;
import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import com.netflix.hystrix.HystrixCircuitBreaker;
import com.netflix.hystrix.HystrixCollapserKey;
import com.netflix.hystrix.HystrixCollapserMetrics;
import com.netflix.hystrix.HystrixCommandKey;
import com.netflix.hystrix.HystrixCommandMetrics;
import com.netflix.hystrix.HystrixCommandMetrics.HealthCounts;
import com.netflix.hystrix.HystrixCommandProperties;
import com.netflix.hystrix.HystrixEventType;
import com.netflix.hystrix.HystrixThreadPoolKey;
import com.netflix.hystrix.HystrixThreadPoolMetrics;
import com.netflix.hystrix.util.PlatformSpecific;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import rx.functions.Func0;
import java.io.IOException;
import java.io.StringWriter;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* Polls Hystrix metrics and output JSON strings for each metric to a MetricsPollerListener.
* <p>
* Polling can be stopped/started. Use shutdown() to permanently shutdown the poller.
*
* An implementation note. If there's a version mismatch between hystrix-core and hystrix-metrics-event-stream,
* the code below may reference a HystrixEventType that does not exist in hystrix-core. If this happens,
* a j.l.NoSuchFieldError occurs. Since this data is not being generated by hystrix-core, it's safe to count it as 0
* and we should log an error to get users to update their dependency set.
*
* @deprecated Prefer {@link com.netflix.hystrix.metric.consumer.HystrixDashboardStream}
*/
@Deprecated //since 1.5.4
public class HystrixMetricsPoller {
static final Logger logger = LoggerFactory.getLogger(HystrixMetricsPoller.class);
private final ScheduledExecutorService executor;
private final int delay;
private final AtomicBoolean running = new AtomicBoolean(false);
private volatile ScheduledFuture<?> scheduledTask = null;
private final MetricsAsJsonPollerListener listener;
/**
* Allocate resources to begin polling.
* <p>
* Use <code>start</code> to begin polling.
* <p>
* Use <code>shutdown</code> to cleanup resources and stop polling.
* <p>
* Use <code>pause</code> to temporarily stop polling that can be restarted again with <code>start</code>.
*
* @param listener for callbacks
* @param delay
*/
public HystrixMetricsPoller(MetricsAsJsonPollerListener listener, int delay) {
this.listener = listener;
ThreadFactory threadFactory = null;
if (!PlatformSpecific.isAppEngineStandardEnvironment()) {
threadFactory = new MetricsPollerThreadFactory();
} else {
threadFactory = PlatformSpecific.getAppEngineThreadFactory();
}
executor = new ScheduledThreadPoolExecutor(1, threadFactory);
this.delay = delay;
}
/**
* Start polling.
*/
public synchronized void start() {
// use compareAndSet to make sure it starts only once and when not running
if (running.compareAndSet(false, true)) {
logger.debug("Starting HystrixMetricsPoller");
try {
scheduledTask = executor.scheduleWithFixedDelay(new MetricsPoller(listener), 0, delay, TimeUnit.MILLISECONDS);
} catch (Throwable ex) {
logger.error("Exception while creating the MetricsPoller task");
ex.printStackTrace();
running.set(false);
}
}
}
/**
* Pause (stop) polling. Polling can be started again with <code>start</code> as long as <code>shutdown</code> is not called.
*/
public synchronized void pause() {
// use compareAndSet to make sure it stops only once and when running
if (running.compareAndSet(true, false)) {
logger.debug("Stopping the HystrixMetricsPoller");
scheduledTask.cancel(true);
} else {
logger.debug("Attempted to pause a stopped poller");
}
}
/**
* Stops polling and shuts down the ExecutorService.
* <p>
* This instance can no longer be used after calling shutdown.
*/
public synchronized void shutdown() {
pause();
executor.shutdown();
}
public boolean isRunning() {
return running.get();
}
/**
* Used to protect against leaking ExecutorServices and threads if this class is abandoned for GC without shutting down.
*/
@SuppressWarnings("unused")
private final Object finalizerGuardian = new Object() {
protected void finalize() throws Throwable {
if (!executor.isShutdown()) {
logger.warn("{} was not shutdown. Caught in Finalize Guardian and shutting down.", HystrixMetricsPoller.class.getSimpleName());
try {
shutdown();
} catch (Exception e) {
logger.error("Failed to shutdown {}", HystrixMetricsPoller.class.getSimpleName(), e);
}
}
};
};
public static interface MetricsAsJsonPollerListener {
public void handleJsonMetric(String json);
}
private class MetricsPoller implements Runnable {
private final MetricsAsJsonPollerListener listener;
private final JsonFactory jsonFactory = new JsonFactory();
public MetricsPoller(MetricsAsJsonPollerListener listener) {
this.listener = listener;
}
@Override
public void run() {
try {
for (HystrixCommandMetrics commandMetrics : HystrixCommandMetrics.getInstances()) {
String jsonString = getCommandJson(commandMetrics);
listener.handleJsonMetric(jsonString);
}
for (HystrixThreadPoolMetrics threadPoolMetrics : HystrixThreadPoolMetrics.getInstances()) {
if (hasExecutedCommandsOnThread(threadPoolMetrics)) {
String jsonString = getThreadPoolJson(threadPoolMetrics);
listener.handleJsonMetric(jsonString);
}
}
for (HystrixCollapserMetrics collapserMetrics : HystrixCollapserMetrics.getInstances()) {
String jsonString = getCollapserJson(collapserMetrics);
listener.handleJsonMetric(jsonString);
}
} catch (Exception e) {
logger.warn("Failed to output metrics as JSON", e);
// shutdown
pause();
return;
}
}
private void safelyWriteNumberField(JsonGenerator json, String name, Func0<Long> metricGenerator) throws IOException {
try {
json.writeNumberField(name, metricGenerator.call());
} catch (NoSuchFieldError error) {
logger.error("While publishing Hystrix metrics stream, error looking up eventType for : {}. Please check that all Hystrix versions are the same!", name);
json.writeNumberField(name, 0L);
}
}
private String getCommandJson(final HystrixCommandMetrics commandMetrics) throws IOException {
HystrixCommandKey key = commandMetrics.getCommandKey();
HystrixCircuitBreaker circuitBreaker = HystrixCircuitBreaker.Factory.getInstance(key);
StringWriter jsonString = new StringWriter();
JsonGenerator json = jsonFactory.createGenerator(jsonString);
json.writeStartObject();
json.writeStringField("type", "HystrixCommand");
json.writeStringField("name", key.name());
json.writeStringField("group", commandMetrics.getCommandGroup().name());
json.writeNumberField("currentTime", System.currentTimeMillis());
// circuit breaker
if (circuitBreaker == null) {
// circuit breaker is disabled and thus never open
json.writeBooleanField("isCircuitBreakerOpen", false);
} else {
json.writeBooleanField("isCircuitBreakerOpen", circuitBreaker.isOpen());
}
HealthCounts healthCounts = commandMetrics.getHealthCounts();
json.writeNumberField("errorPercentage", healthCounts.getErrorPercentage());
json.writeNumberField("errorCount", healthCounts.getErrorCount());
json.writeNumberField("requestCount", healthCounts.getTotalRequests());
// rolling counters
safelyWriteNumberField(json, "rollingCountBadRequests", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.BAD_REQUEST);
}
});
safelyWriteNumberField(json, "rollingCountCollapsedRequests", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.COLLAPSED);
}
});
safelyWriteNumberField(json, "rollingCountEmit", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.EMIT);
}
});
safelyWriteNumberField(json, "rollingCountExceptionsThrown", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.EXCEPTION_THROWN);
}
});
safelyWriteNumberField(json, "rollingCountFailure", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.FAILURE);
}
});
safelyWriteNumberField(json, "rollingCountFallbackEmit", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.FALLBACK_EMIT);
}
});
safelyWriteNumberField(json, "rollingCountFallbackFailure", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.FALLBACK_FAILURE);
}
});
safelyWriteNumberField(json, "rollingCountFallbackMissing", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.FALLBACK_MISSING);
}
});
safelyWriteNumberField(json, "rollingCountFallbackRejection", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.FALLBACK_REJECTION);
}
});
safelyWriteNumberField(json, "rollingCountFallbackSuccess", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.FALLBACK_SUCCESS);
}
});
safelyWriteNumberField(json, "rollingCountResponsesFromCache", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.RESPONSE_FROM_CACHE);
}
});
safelyWriteNumberField(json, "rollingCountSemaphoreRejected", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.SEMAPHORE_REJECTED);
}
});
safelyWriteNumberField(json, "rollingCountShortCircuited", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.SHORT_CIRCUITED);
}
});
safelyWriteNumberField(json, "rollingCountSuccess", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.SUCCESS);
}
});
safelyWriteNumberField(json, "rollingCountThreadPoolRejected", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.THREAD_POOL_REJECTED);
}
});
safelyWriteNumberField(json, "rollingCountTimeout", new Func0<Long>() {
@Override
public Long call() {
return commandMetrics.getRollingCount(HystrixEventType.TIMEOUT);
}
});
json.writeNumberField("currentConcurrentExecutionCount", commandMetrics.getCurrentConcurrentExecutionCount());
json.writeNumberField("rollingMaxConcurrentExecutionCount", commandMetrics.getRollingMaxConcurrentExecutions());
// latency percentiles
json.writeNumberField("latencyExecute_mean", commandMetrics.getExecutionTimeMean());
json.writeObjectFieldStart("latencyExecute");
json.writeNumberField("0", commandMetrics.getExecutionTimePercentile(0));
json.writeNumberField("25", commandMetrics.getExecutionTimePercentile(25));
json.writeNumberField("50", commandMetrics.getExecutionTimePercentile(50));
json.writeNumberField("75", commandMetrics.getExecutionTimePercentile(75));
json.writeNumberField("90", commandMetrics.getExecutionTimePercentile(90));
json.writeNumberField("95", commandMetrics.getExecutionTimePercentile(95));
json.writeNumberField("99", commandMetrics.getExecutionTimePercentile(99));
json.writeNumberField("99.5", commandMetrics.getExecutionTimePercentile(99.5));
json.writeNumberField("100", commandMetrics.getExecutionTimePercentile(100));
json.writeEndObject();
//
json.writeNumberField("latencyTotal_mean", commandMetrics.getTotalTimeMean());
json.writeObjectFieldStart("latencyTotal");
json.writeNumberField("0", commandMetrics.getTotalTimePercentile(0));
json.writeNumberField("25", commandMetrics.getTotalTimePercentile(25));
json.writeNumberField("50", commandMetrics.getTotalTimePercentile(50));
json.writeNumberField("75", commandMetrics.getTotalTimePercentile(75));
json.writeNumberField("90", commandMetrics.getTotalTimePercentile(90));
json.writeNumberField("95", commandMetrics.getTotalTimePercentile(95));
json.writeNumberField("99", commandMetrics.getTotalTimePercentile(99));
json.writeNumberField("99.5", commandMetrics.getTotalTimePercentile(99.5));
json.writeNumberField("100", commandMetrics.getTotalTimePercentile(100));
json.writeEndObject();
// property values for reporting what is actually seen by the command rather than what was set somewhere
HystrixCommandProperties commandProperties = commandMetrics.getProperties();
json.writeNumberField("propertyValue_circuitBreakerRequestVolumeThreshold", commandProperties.circuitBreakerRequestVolumeThreshold().get());
json.writeNumberField("propertyValue_circuitBreakerSleepWindowInMilliseconds", commandProperties.circuitBreakerSleepWindowInMilliseconds().get());
json.writeNumberField("propertyValue_circuitBreakerErrorThresholdPercentage", commandProperties.circuitBreakerErrorThresholdPercentage().get());
json.writeBooleanField("propertyValue_circuitBreakerForceOpen", commandProperties.circuitBreakerForceOpen().get());
json.writeBooleanField("propertyValue_circuitBreakerForceClosed", commandProperties.circuitBreakerForceClosed().get());
json.writeBooleanField("propertyValue_circuitBreakerEnabled", commandProperties.circuitBreakerEnabled().get());
json.writeStringField("propertyValue_executionIsolationStrategy", commandProperties.executionIsolationStrategy().get().name());
json.writeNumberField("propertyValue_executionIsolationThreadTimeoutInMilliseconds", commandProperties.executionTimeoutInMilliseconds().get());
json.writeNumberField("propertyValue_executionTimeoutInMilliseconds", commandProperties.executionTimeoutInMilliseconds().get());
json.writeBooleanField("propertyValue_executionIsolationThreadInterruptOnTimeout", commandProperties.executionIsolationThreadInterruptOnTimeout().get());
json.writeStringField("propertyValue_executionIsolationThreadPoolKeyOverride", commandProperties.executionIsolationThreadPoolKeyOverride().get());
json.writeNumberField("propertyValue_executionIsolationSemaphoreMaxConcurrentRequests", commandProperties.executionIsolationSemaphoreMaxConcurrentRequests().get());
json.writeNumberField("propertyValue_fallbackIsolationSemaphoreMaxConcurrentRequests", commandProperties.fallbackIsolationSemaphoreMaxConcurrentRequests().get());
/*
* The following are commented out as these rarely change and are verbose for streaming for something people don't change.
* We could perhaps allow a property or request argument to include these.
*/
// json.put("propertyValue_metricsRollingPercentileEnabled", commandProperties.metricsRollingPercentileEnabled().get());
// json.put("propertyValue_metricsRollingPercentileBucketSize", commandProperties.metricsRollingPercentileBucketSize().get());
// json.put("propertyValue_metricsRollingPercentileWindow", commandProperties.metricsRollingPercentileWindowInMilliseconds().get());
// json.put("propertyValue_metricsRollingPercentileWindowBuckets", commandProperties.metricsRollingPercentileWindowBuckets().get());
// json.put("propertyValue_metricsRollingStatisticalWindowBuckets", commandProperties.metricsRollingStatisticalWindowBuckets().get());
json.writeNumberField("propertyValue_metricsRollingStatisticalWindowInMilliseconds", commandProperties.metricsRollingStatisticalWindowInMilliseconds().get());
json.writeBooleanField("propertyValue_requestCacheEnabled", commandProperties.requestCacheEnabled().get());
json.writeBooleanField("propertyValue_requestLogEnabled", commandProperties.requestLogEnabled().get());
json.writeNumberField("reportingHosts", 1); // this will get summed across all instances in a cluster
json.writeStringField("threadPool", commandMetrics.getThreadPoolKey().name());
json.writeEndObject();
json.close();
return jsonString.getBuffer().toString();
}
private boolean hasExecutedCommandsOnThread(HystrixThreadPoolMetrics threadPoolMetrics) {
return threadPoolMetrics.getCurrentCompletedTaskCount().intValue() > 0;
}
private String getThreadPoolJson(final HystrixThreadPoolMetrics threadPoolMetrics) throws IOException {
HystrixThreadPoolKey key = threadPoolMetrics.getThreadPoolKey();
StringWriter jsonString = new StringWriter();
JsonGenerator json = jsonFactory.createJsonGenerator(jsonString);
json.writeStartObject();
json.writeStringField("type", "HystrixThreadPool");
json.writeStringField("name", key.name());
json.writeNumberField("currentTime", System.currentTimeMillis());
json.writeNumberField("currentActiveCount", threadPoolMetrics.getCurrentActiveCount().intValue());
json.writeNumberField("currentCompletedTaskCount", threadPoolMetrics.getCurrentCompletedTaskCount().longValue());
json.writeNumberField("currentCorePoolSize", threadPoolMetrics.getCurrentCorePoolSize().intValue());
json.writeNumberField("currentLargestPoolSize", threadPoolMetrics.getCurrentLargestPoolSize().intValue());
json.writeNumberField("currentMaximumPoolSize", threadPoolMetrics.getCurrentMaximumPoolSize().intValue());
json.writeNumberField("currentPoolSize", threadPoolMetrics.getCurrentPoolSize().intValue());
json.writeNumberField("currentQueueSize", threadPoolMetrics.getCurrentQueueSize().intValue());
json.writeNumberField("currentTaskCount", threadPoolMetrics.getCurrentTaskCount().longValue());
safelyWriteNumberField(json, "rollingCountThreadsExecuted", new Func0<Long>() {
@Override
public Long call() {
return threadPoolMetrics.getRollingCount(HystrixEventType.ThreadPool.EXECUTED);
}
});
json.writeNumberField("rollingMaxActiveThreads", threadPoolMetrics.getRollingMaxActiveThreads());
safelyWriteNumberField(json, "rollingCountCommandRejections", new Func0<Long>() {
@Override
public Long call() {
return threadPoolMetrics.getRollingCount(HystrixEventType.ThreadPool.REJECTED);
}
});
json.writeNumberField("propertyValue_queueSizeRejectionThreshold", threadPoolMetrics.getProperties().queueSizeRejectionThreshold().get());
json.writeNumberField("propertyValue_metricsRollingStatisticalWindowInMilliseconds", threadPoolMetrics.getProperties().metricsRollingStatisticalWindowInMilliseconds().get());
json.writeNumberField("reportingHosts", 1); // this will get summed across all instances in a cluster
json.writeEndObject();
json.close();
return jsonString.getBuffer().toString();
}
private String getCollapserJson(final HystrixCollapserMetrics collapserMetrics) throws IOException {
HystrixCollapserKey key = collapserMetrics.getCollapserKey();
StringWriter jsonString = new StringWriter();
JsonGenerator json = jsonFactory.createJsonGenerator(jsonString);
json.writeStartObject();
json.writeStringField("type", "HystrixCollapser");
json.writeStringField("name", key.name());
json.writeNumberField("currentTime", System.currentTimeMillis());
safelyWriteNumberField(json, "rollingCountRequestsBatched", new Func0<Long>() {
@Override
public Long call() {
return collapserMetrics.getRollingCount(HystrixEventType.Collapser.ADDED_TO_BATCH);
}
});
safelyWriteNumberField(json, "rollingCountBatches", new Func0<Long>() {
@Override
public Long call() {
return collapserMetrics.getRollingCount(HystrixEventType.Collapser.BATCH_EXECUTED);
}
});
safelyWriteNumberField(json, "rollingCountResponsesFromCache", new Func0<Long>() {
@Override
public Long call() {
return collapserMetrics.getRollingCount(HystrixEventType.Collapser.RESPONSE_FROM_CACHE);
}
});
// batch size percentiles
json.writeNumberField("batchSize_mean", collapserMetrics.getBatchSizeMean());
json.writeObjectFieldStart("batchSize");
json.writeNumberField("25", collapserMetrics.getBatchSizePercentile(25));
json.writeNumberField("50", collapserMetrics.getBatchSizePercentile(50));
json.writeNumberField("75", collapserMetrics.getBatchSizePercentile(75));
json.writeNumberField("90", collapserMetrics.getBatchSizePercentile(90));
json.writeNumberField("95", collapserMetrics.getBatchSizePercentile(95));
json.writeNumberField("99", collapserMetrics.getBatchSizePercentile(99));
json.writeNumberField("99.5", collapserMetrics.getBatchSizePercentile(99.5));
json.writeNumberField("100", collapserMetrics.getBatchSizePercentile(100));
json.writeEndObject();
// shard size percentiles (commented-out for now)
//json.writeNumberField("shardSize_mean", collapserMetrics.getShardSizeMean());
//json.writeObjectFieldStart("shardSize");
//json.writeNumberField("25", collapserMetrics.getShardSizePercentile(25));
//json.writeNumberField("50", collapserMetrics.getShardSizePercentile(50));
//json.writeNumberField("75", collapserMetrics.getShardSizePercentile(75));
//json.writeNumberField("90", collapserMetrics.getShardSizePercentile(90));
//json.writeNumberField("95", collapserMetrics.getShardSizePercentile(95));
//json.writeNumberField("99", collapserMetrics.getShardSizePercentile(99));
//json.writeNumberField("99.5", collapserMetrics.getShardSizePercentile(99.5));
//json.writeNumberField("100", collapserMetrics.getShardSizePercentile(100));
//json.writeEndObject();
//json.writeNumberField("propertyValue_metricsRollingStatisticalWindowInMilliseconds", collapserMetrics.getProperties().metricsRollingStatisticalWindowInMilliseconds().get());
json.writeBooleanField("propertyValue_requestCacheEnabled", collapserMetrics.getProperties().requestCacheEnabled().get());
json.writeNumberField("propertyValue_maxRequestsInBatch", collapserMetrics.getProperties().maxRequestsInBatch().get());
json.writeNumberField("propertyValue_timerDelayInMilliseconds", collapserMetrics.getProperties().timerDelayInMilliseconds().get());
json.writeNumberField("reportingHosts", 1); // this will get summed across all instances in a cluster
json.writeEndObject();
json.close();
return jsonString.getBuffer().toString();
}
}
private static class MetricsPollerThreadFactory implements ThreadFactory {
private static final String MetricsThreadName = "HystrixMetricPoller";
private final ThreadFactory defaultFactory = Executors.defaultThreadFactory();
public Thread newThread(Runnable r) {
Thread thread = defaultFactory.newThread(r);
thread.setName(MetricsThreadName);
thread.setDaemon(true);
return thread;
}
}
}