com.twitter.heron.api.metric.GlobalMetrics Maven / Gradle / Ivy
// Copyright 2017 Twitter. 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.
// 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.
/**
* 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 com.twitter.heron.api.metric;
import java.io.Serializable;
import java.time.Duration;
/**
* Singleton class which exposes a simple globally available counter for heron jobs.
* Anywhere in the execution of heron job, user can put-
* GlobalMetrics.incr("mycounter") to add a counter. There will be no need to
* explicitly declare the counter before. If the counter doesn't exist it will be created.
* The creation is lazy which means, unless the counter not being available, it is counted as 0
* CounterFactory.init() should be called in prepare and open methods of bolt and spout respectively.
* The counters will be named __auto__/mycounter (note the __auto__ prefix)
*/
public enum GlobalMetrics implements Serializable {
INSTANCE;
public static final String ROOT_NAME = "__auto__";
private MultiCountMetric metricsContainer;
private boolean registered;
GlobalMetrics() {
metricsContainer = new MultiCountMetric();
registered = false;
}
/**
* Not thread safe increment of counterName. Counter doesn't exist unless incremented once
*/
public static void incr(String counterName) {
INSTANCE.metricsContainer.scope(counterName).incr();
}
/**
* Not thread safe 'incrementing by' of counterName. Counter doesn't exist unless incremented once
*/
public static void incrBy(String counterName, int incrValue) {
INSTANCE.metricsContainer.scope(counterName).incrBy(incrValue);
}
/**
* Thread safe created increment of counterName. (Slow)
*/
public static void safeIncr(String counterName) {
synchronized (INSTANCE) {
if (INSTANCE.registered) {
INSTANCE.metricsContainer.scope(counterName).incr();
}
}
}
/**
* Thread safe created increment of counterName. (Slow)
*/
public static void safeIncrBy(String counterName, int incrValue) {
synchronized (INSTANCE) {
if (INSTANCE.registered) {
INSTANCE.metricsContainer.scope(counterName).incrBy(incrValue);
}
}
}
/**
* Initialize the counter by registering the metricContainer. Should be done in open/prepare call.
* TODO: Investigate if it is possible to do this part in ctor. One thing to note is how this will
* affect the serialization of CounterFactory.
*/
public static void init(IMetricsRegister metricsRegister, Duration metricsBucket) {
synchronized (INSTANCE) {
if (!INSTANCE.registered) {
metricsRegister.registerMetric(
ROOT_NAME, INSTANCE.metricsContainer, (int) metricsBucket.getSeconds());
INSTANCE.registered = true;
}
}
}
/**
* test-only
*/
public static MultiCountMetric getUnderlyingCounter() {
return INSTANCE.metricsContainer;
}
/**
* During serialization don't create a copy of this class. 'readResolve' is used by reflection
* for java serialization.
*/
protected Object readResolve() {
return INSTANCE;
}
}