【Spring Boot】Spring Boot之利用Logstash将日志转换成以JSON的格式存储和输出

一、Logstash的作用

　　Logstash是一个完全开源的工具，它可以对日志进行收集、过滤，能非常方便地将日志转换成以JSON的格式存储和输出，并将其存储供以后使用。

二、整合Logstash的步骤

注意：需要在logback日志框架的基础上：https://www.cnblogs.com/756623607-zhang/p/9695131.html

1）增加pom依赖

   　　　　　　<!--logstash-->
            <dependency>
                <groupId>net.logstash.logback</groupId>
                <artifactId>logstash-logback-encoder</artifactId>
                <version>5.2</version>
            </dependency>

2）logback配置文件增加Logstash的appender

    <!-- LOGSTASH -->
    <appender name="FILE-LOGSTASH" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${logback.path}/${application.name}-logstash.log</file>
        <append>true</append>
        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
            <fileNamePattern>${logback.path}/${application.name}-logstash.%d{yyyy-MM-dd}.%i.log.gz</fileNamePattern>
            <maxHistory>${logback.max-history}</maxHistory>
            <maxFileSize>${logback.max-file-size}</maxFileSize>
        </rollingPolicy>

        <encoder class="net.logstash.logback.encoder.LoggingEventCompositeJsonEncoder">
            <providers>
                <timestamp>
                    <timeZone>UTC</timeZone>
                </timestamp>
                <pattern>
                    <pattern>
                        {
                        "severity": "%level",
                        "service": "${springAppName:-}",
                        "trace": "%X{X-B3-TraceId:-}",
                        "span": "%X{X-B3-SpanId:-}",
                        "exportable": "%X{X-Span-Export:-}",
                        "pid": "${PID:-}",
                        "thread": "%thread",
                        "class": "%logger{40}",
                        "rest": "%message"
                        }
                    </pattern>
                </pattern>
            </providers>
        </encoder>
    </appender>

3）引用该appender

 <root level="${logback.root-level}">
        <appender-ref ref="FILE-LOGSTASH"/>
  </root>