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。