第三十二章 elk（3）- broker架构 + 引入logback

实际中最好用的日志框架是logback，我们现在会直接使用logback通过tcp协议向logstash-shipper输入日志数据。在上一节的基础上修改！！！

一、代码

1、pom.xml

        <!-- logstash-logback -->
        <dependency>
            <groupId>net.logstash.logback</groupId>
            <artifactId>logstash-logback-encoder</artifactId>
            <version>4.6</version>
        </dependency>

2、application.properties

#set logstash shipper host
logstash.host=127.0.0.1
#set logstash shipper port
logstash.port=4560
logstash.level=info

3、LogstashProperties.java

package com.xxx.secondboot.logstash;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

import lombok.Getter;
import lombok.Setter;

@Component
@ConfigurationProperties(prefix = "logstash")
@Getter
@Setter
public class LogstashProperties {
    private String host;
    private int    port;
    private String level;
}

4、LogstashConfig.java

package com.xxx.secondboot.logstash;

import java.net.InetSocketAddress;

import javax.annotation.PostConstruct;

import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import ch.qos.logback.classic.Level;
import ch.qos.logback.classic.Logger;
import net.logstash.logback.appender.LogstashTcpSocketAppender;
import net.logstash.logback.encoder.LogstashEncoder;

/**
 * 该类是可以配置成xml配置文件的，但是那样的话，就不能由客户端指定参数了
 */
@Component
public class LogstashConfig {
    @Autowired
    private LogstashProperties logstashProperties;

    @PostConstruct
    public void init() {
        Logger rootLogger = (Logger) LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME);
        LogstashTcpSocketAppender appender = new LogstashTcpSocketAppender();
        appender.setName("stash");
        appender.addDestinations(new InetSocketAddress(logstashProperties.getHost(), logstashProperties.getPort()));
       
        LogstashEncoder encoder = new LogstashEncoder();
        encoder.setCustomFields("{ "service":"" + "myboot2" + ""}");//服务名会在日志中显示（可以方便的知道该日志是哪个服务的）
        encoder.start();
        
        appender.setEncoder(encoder);
        appender.setContext(rootLogger.getLoggerContext());
        appender.start();
        rootLogger.addAppender(appender);
        rootLogger.setLevel(Level.toLevel(logstashProperties.getLevel()));
    }
}

注意：

• init()方法在LogstashConfig bean构建之后执行，之后的日志信息都会写入到LogstashTcpSocketAppender中去
• 2、3、4其实也可以没有，直接使用xml配置即可（参考：https://github.com/logstash/logstash-logback-encoder/tree/logstash-logback-encoder-4.7），但是这样的话，就无法有我们自己指定logstash参数了，或者需要在xml中指定（这里的配置不在consul中配置），而配在application.properties中（实际上就是配在了consul中）

5、AdviceController.java

private static final Logger LOGGER = LoggerFactory.getLogger(AdviceController.class);

    @RequestMapping(value = "/testLog", method = RequestMethod.GET)
    public String testLog() {
        LOGGER.info("test info");
        LOGGER.debug("test debug");
        LOGGER.error("test error");
        LOGGER.warn("test warn");
        return "test logstash-logback";
    }

二、测试

在上一节的基础上修改logstash-shipper的配置文件：（输入为tcp，配置参考：https://github.com/logstash/logstash-logback-encoder/tree/logstash-logback-encoder-4.7）

input {
    tcp {
        mode => "server"
        host => "127.0.0.1"
        port => 4560
        codec => "json_lines"
    }
}

filter {
    
}

output {
    redis{
        data_type => "list"
        host => ["127.0.0.1:6379"]
        key => "microservice:logstash:redis"
    }
}

之后运行启动程序，这时候kibana就会打印出启动日志了，在日志中有servicename的体现，之后访问swagger，我们会发现3条不同级别的日志都进入kibana进行展示了。