org.springframework.boot.actuate.health.AbstractHealthIndicator Maven / Gradle / Ivy
/*
* Copyright 2012-2018 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
*
* https://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.boot.actuate.health;
import java.util.function.Function;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.boot.actuate.health.Health.Builder;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
/**
* Base {@link HealthIndicator} implementations that encapsulates creation of
* {@link Health} instance and error handling.
*
* This implementation is only suitable if an {@link Exception} raised from
* {@link #doHealthCheck(org.springframework.boot.actuate.health.Health.Builder)} should
* create a {@link Status#DOWN} health status.
*
* @author Christian Dupuis
* @since 1.1.0
*/
public abstract class AbstractHealthIndicator implements HealthIndicator {
private static final String NO_MESSAGE = null;
private static final String DEFAULT_MESSAGE = "Health check failed";
private final Log logger = LogFactory.getLog(getClass());
private final Function healthCheckFailedMessage;
/**
* Create a new {@link AbstractHealthIndicator} instance with a default
* {@code healthCheckFailedMessage}.
*/
protected AbstractHealthIndicator() {
this(NO_MESSAGE);
}
/**
* Create a new {@link AbstractHealthIndicator} instance with a specific message to
* log when the health check fails.
* @param healthCheckFailedMessage the message to log on health check failure
* @since 2.0.0
*/
protected AbstractHealthIndicator(String healthCheckFailedMessage) {
this.healthCheckFailedMessage = (ex) -> healthCheckFailedMessage;
}
/**
* Create a new {@link AbstractHealthIndicator} instance with a specific message to
* log when the health check fails.
* @param healthCheckFailedMessage the message to log on health check failure
* @since 2.0.0
*/
protected AbstractHealthIndicator(
Function healthCheckFailedMessage) {
Assert.notNull(healthCheckFailedMessage,
"HealthCheckFailedMessage must not be null");
this.healthCheckFailedMessage = healthCheckFailedMessage;
}
@Override
public final Health health() {
Health.Builder builder = new Health.Builder();
try {
doHealthCheck(builder);
}
catch (Exception ex) {
if (this.logger.isWarnEnabled()) {
String message = this.healthCheckFailedMessage.apply(ex);
this.logger.warn(StringUtils.hasText(message) ? message : DEFAULT_MESSAGE,
ex);
}
builder.down(ex);
}
return builder.build();
}
/**
* Actual health check logic.
* @param builder the {@link Builder} to report health status and details
* @throws Exception any {@link Exception} that should create a {@link Status#DOWN}
* system status.
*/
protected abstract void doHealthCheck(Health.Builder builder) throws Exception;
}