com.github.jmnarloch.spring.cloud.config.refresh.ConfigClientRefreshAutoConfiguration.java Source code

Introduction

Here is the source code for com.github.jmnarloch.spring.cloud.config.refresh.ConfigClientRefreshAutoConfiguration.java

Source

/**
 * Copyright (c) 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 com.github.jmnarloch.spring.cloud.config.refresh;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.autoconfigure.AutoConfigureAfter;
import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.cloud.autoconfigure.RefreshAutoConfiguration;
import org.springframework.cloud.bootstrap.config.RefreshEndpoint;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.ScheduledAnnotationBeanPostProcessor;
import org.springframework.scheduling.annotation.SchedulingConfigurer;
import org.springframework.scheduling.config.IntervalTask;
import org.springframework.scheduling.config.ScheduledTaskRegistrar;

/**
 * Sets up pulling configuration from the config server as fixed ratio. This will periodically perform entire endpoint
 * refresh which is similar of manually invoking HTTP POST '/refresh' endpoint causing to ake an request to config
 * server and retrieve the up to date settings and afterwards reload all {@code @RefreshScope} beans.
 *
 * @author Jakub Narloch
 */
@ConditionalOnBean({ RefreshEndpoint.class })
@ConditionalOnProperty("spring.cloud.config.refreshInterval")
@AutoConfigureAfter(RefreshAutoConfiguration.class)
@Configuration
public class ConfigClientRefreshAutoConfiguration implements SchedulingConfigurer {

    /**
     * Logger used by this class.
     */
    private static final Log logger = LogFactory.getLog(ConfigClientRefreshAutoConfiguration.class);

    /**
     * The interval after which the refresh will be perform in seconds.
     */
    @Value("${spring.cloud.config.refreshInterval}")
    private long refreshInterval;

    /**
     * The refresh endpoint
     */
    @Autowired
    private RefreshEndpoint refreshEndpoint;

    /**
     * Configures the scheduler by registering task responsible for periodically refreshing entire endpoint.
     *
     * @param taskRegistrar the task registrar
     */
    @Override
    public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {

        final long interval = getRefreshIntervalInMilliseconds();

        logger.info(String.format("Scheduling config refresh task with %s second delay", refreshInterval));

        taskRegistrar.addFixedDelayTask(new IntervalTask(new Runnable() {
            @Override
            public void run() {
                refreshEndpoint.refresh();
            }
        }, interval, interval));
    }

    /**
     * Returns the refresh interval in milliseconds.
     *
     * @return the interval in milliseconds.
     */
    private long getRefreshIntervalInMilliseconds() {

        return refreshInterval * 1000;
    }

    /**
     * Enables the scheduler if none has been registered in the context.
     *
     * @author Jakub Narloch
     */
    @ConditionalOnMissingBean(ScheduledAnnotationBeanPostProcessor.class)
    @EnableScheduling
    @Configuration
    protected static class EnableSchedulingConfigProperties {

    }
}