本文節選自《Netkiller Java 手札》

5.31. Spring boot with ELK(Elasticsearch + Logstash + Kibana)

將 Spring boot 日誌寫入 ELK 有多種實現方式，這裡僅提供三種方案：

1. Spring boot -> logback -> Tcp/IP -> logstash -> elasticsearch 這種方式實現非常方便不需要而外包或者軟體
2. Spring boot -> logback -> Redis -> logstash -> elasticsearch 利用 Redis 提供的釋出訂閱功能將日誌投遞到 elasticsearch
3. Spring boot -> logback -> Kafka -> logstash -> elasticsearch Kafka 方法適合大資料的情況。

5.31.1. TCP 方案

logstash 配置

			input {
  tcp {
    host => "172.16.1.16" 
    port => 9250
    mode => "server"
    tags => ["tags"]
    codec => json_lines  //可能需要更新logstash外掛
  }
}

output {
 stdout{codec =>rubydebug}
  elasticsearch {
   hosts => ["localhost:9200"]  //這塊配置需要帶埠號
    flush_size => 1000

  }
}			
 

Spring boot logback.xml 配置

			<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <property resource="properties/logback-variables.properties" /> 

    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <encoder charset="UTF-8">
            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger - %msg%n
            </pattern>
        </encoder>
    </appender>
    <appender name="LOGSTASH" class="net.logstash.logback.appender.LogstashTcpSocketAppender">
        <destination>172.16.1.16:9250</destination>
        <encoder charset="UTF-8" class="net.logstash.logback.encoder.LogstashEncoder" />
    </appender>

    <!--<appender name="async" class="ch.qos.logback.classic.AsyncAppender">-->
        <!--<appender-ref ref="stash" />-->
    <!--</appender>-->
    
    <root level="info">                    <!-- 設定日誌級別 -->
        <appender-ref ref="STDOUT" />
        <appender-ref ref="LOGSTASH" />
    </root>
</configuration>			
 

5.31.2. Redis 方案

Maven pom.xml 增加 Logback Redis 依賴

			<!-- https://mvnrepository.com/artifact/com.cwbase/logback-redis-appender -->
<dependency>
    <groupId>com.cwbase</groupId>
    <artifactId>logback-redis-appender</artifactId>
    <version>1.1.5</version>
</dependency>			

Spring boot logback.xml 配置

			<?xml version="1.0" encoding="UTF-8"?>
<configuration>
	<include resource="org/springframework/boot/logging/logback/defaults.xml" />
	<include resource="org/springframework/boot/logging/logback/file-appender.xml" />
	<property name="type.name" value="test" />
	<appender name="LOGSTASH" class="com.cwbase.logback.RedisAppender">
		<source>spring-application</source>
		<type>${type.name}</type>
		<host>localhost</host>
		<key>logstash:redis</key>
		<tags>test-2</tags>
		<mdc>true</mdc>
		<location>true</location>
		<callerStackIndex>0</callerStackIndex>
		<!--additionalField新增附加欄位 用於head外掛顯示 -->
		<additionalField>
			<key>MyKey</key>
			<value>MyValue</value>
		</additionalField>
		<additionalField>
			<key>MySecondKey</key>
			<value>MyOtherValue</value>
		</additionalField>
	</appender>
	<root level="INFO">
		<appender-ref ref="FILE" />
		<appender-ref ref="LOGSTASH" />
	</root>
</configuration>			

logstash 配置

			input {
    redis {
        host => 'localhost'
        data_type => 'list'
        port => "6379"
        key => 'logstash:redis' #自定義
        type => 'redis-input'   #自定義
    }
}
output {
    elasticsearch {
        host => "localhost" 
        codec => "json"
        protocol => "http"
    }
}			

5.31.3. Kafka 方案

暫時沒有機器資源，本章節待續