/*
* Copyright 2013-2014 the original author or authors.
*
* 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 org.springframework.cloud.netflix.hystrix;
import java.util.ArrayList;
import java.util.List;
import org.springframework.boot.actuate.health.AbstractHealthIndicator;
import org.springframework.boot.actuate.health.Health.Builder;
import org.springframework.boot.actuate.health.HealthIndicator;
import org.springframework.boot.actuate.health.Status;
import com.netflix.hystrix.HystrixCircuitBreaker;
import com.netflix.hystrix.HystrixCommandMetrics;
/**
* A {@link HealthIndicator} implementation for Hystrix circuit breakers.
* <p>
* This default implementation will not change the system state (e.g. <code>OK</code>) but
* includes all open circuits by name.
*
* @author Christian Dupuis
*/
public class HystrixHealthIndicator extends AbstractHealthIndicator {
private static final Status CIRCUIT_OPEN = new Status("CIRCUIT_OPEN");
@Override
protected void doHealthCheck(Builder builder) throws Exception {
List<String> openCircuitBreakers = new ArrayList<String>();
// Collect all open circuit breakers from Hystrix
for (HystrixCommandMetrics metrics : HystrixCommandMetrics.getInstances()) {
HystrixCircuitBreaker circuitBreaker = HystrixCircuitBreaker.Factory
.getInstance(metrics.getCommandKey());
if (circuitBreaker != null && circuitBreaker.isOpen()) {
openCircuitBreakers.add(metrics.getCommandGroup().name() + "::"
+ metrics.getCommandKey().name());
}
}
// If there is at least one open circuit report OUT_OF_SERVICE adding the command
// group
// and key name
if (openCircuitBreakers.size() > 0) {
builder.status(CIRCUIT_OPEN).withDetail("openCircuitBreakers",
openCircuitBreakers);
}
else {
builder.up();
}
}
}