HeartbeatProperties.java

/*
 * Copyright 2013-2015 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.consul.discovery;

import javax.annotation.PostConstruct;
import javax.validation.constraints.DecimalMax;
import javax.validation.constraints.DecimalMin;
import javax.validation.constraints.Min;
import javax.validation.constraints.NotNull;

import lombok.Data;

import lombok.extern.apachecommons.CommonsLog;
import org.joda.time.Period;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.validation.annotation.Validated;

@ConfigurationProperties(prefix = "spring.cloud.consul.discovery.heartbeat")
@Data
@CommonsLog
@Validated
public class HeartbeatProperties {

	// TODO: change enabled to default to true when I stop seeing messages like
	// [WARN] agent: Check 'service:testConsulApp:xtest:8080' missed TTL, is now critical
	boolean enabled = false;

	@Min(1)
	private int ttlValue = 30;

	@NotNull
	private String ttlUnit = "s";

	@DecimalMin("0.1")
	@DecimalMax("0.9")
	private double intervalRatio = 2.0 / 3.0;

	private Period heartbeatInterval;

	@PostConstruct
	public void init() {
        this.heartbeatInterval = computeHearbeatInterval();
        log.debug("Computed heartbeatInterval: " + heartbeatInterval);
	}

    protected Period computeHearbeatInterval() {
        // heartbeat rate at ratio * ttl, but no later than ttl -1s and, (under lesser
        // priority), no sooner than 1s from now
        double interval = ttlValue * intervalRatio;
        double max = Math.max(interval, 1);
        int ttlMinus1 = ttlValue - 1;
        double min = Math.min(ttlMinus1, max);
        return new Period(Math.round(1000 * min));
    }

    public String getTtl() {
		return ttlValue + ttlUnit;
	}
}