如何使用logback以文本和json格式打印Spring日志？

Question

对于日志记录，我们使用Logback。目前，我们正在使用Splunk查看Spring日志。根据项目要求，我们需要向基巴纳进发。首先，我们应该以JSON格式登录，这样Kibana就可以轻松地处理它。目前，我们并不是用Kibana取代Splunk，但是当与Kibana成功地整合时，我们就可以在所有的项目中逐步取代Splunk。

因此，根据需求，我们需要现有的日志，即文本日志，但为了研究和开发目的，我们也需要JSON日志。

Answer 1

这很简单。您只需在logstash-logback-encoder文件中添加pom.xml依赖项，并在logback.xml文件中编写一些配置即可。请按照以下步骤来满足您的要求。

Step1:在pom.xml中添加logstash-logback-encoder依赖项。

<dependency>
    <groupId>net.logstash.logback</groupId>
    <artifactId>logstash-logback-encoder</artifactId>
    <version>6.4</version>
</dependency>

Step2:在src/main/resources/中创建logback.xml文件并复制粘贴以下内容。

<?xml version="1.0" encoding="UTF-8"?>
<configuration debug="false">
  <include resource="org/springframework/boot/logging/logback/defaults.xml" />
  <include resource="org/springframework/boot/logging/logback/console-appender.xml" />
  <property name="LOG_PATH" value="logs" />
  <property name="CONSOLE_LOG_PATTERN" value="[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %X{id} %c{1} - %msg%n" />
  <property name="FILE_LOG_PATTERN" value="[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %X{id} %c{1} - %msg%n" />

  <appender name="CONSOLE_APPENDER" class="ch.qos.logback.core.ConsoleAppender">
    <encoder>
      <pattern>${CONSOLE_LOG_PATTERN}</pattern>
      <charset>utf8</charset>
    </encoder>
  </appender>

  <appender name="ROLLING_TEXT_FILE_APPENDER" class="ch.qos.logback.core.rolling.RollingFileAppender">
    <file>${LOG_PATH}/application-text.log</file>
    <encoder>
      <Pattern>${FILE_LOG_PATTERN}</Pattern>
    </encoder>
    <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
      <fileNamePattern>${LOG_PATH}/application-text.%d{yyyy-MM-dd}.%i.gz
      </fileNamePattern>
      <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
        <maxFileSize>100MB</maxFileSize>
      </timeBasedFileNamingAndTriggeringPolicy>
      <maxHistory>10</maxHistory>
    </rollingPolicy>
  </appender>
  
  <appender name="ROLLING_JSON_FILE_APPENDER" class="ch.qos.logback.core.rolling.RollingFileAppender">
    <file>${LOG_PATH}/application-json.log</file>
    <encoder class="net.logstash.logback.encoder.LogstashEncoder" />
    <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
      <fileNamePattern>${LOG_PATH}/application-json.%d{yyyy-MM-dd}.%i.gz
      </fileNamePattern>
      <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
        <maxFileSize>100MB</maxFileSize>
      </timeBasedFileNamingAndTriggeringPolicy>
      <maxHistory>10</maxHistory>
    </rollingPolicy>
  </appender>

  <root level="INFO">
    <appender-ref ref="CONSOLE_APPENDER" />
    <appender-ref ref="ROLLING_TEXT_FILE_APPENDER" />
    <appender-ref ref="ROLLING_JSON_FILE_APPENDER" />
  </root>
</configuration>

Step3:现在您可以在类中的任何地方使用log语句。假设您在Spring的主要类中使用。

import org.slf4j.MDC;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import com.altafjava.constant.AppConstant;
import lombok.extern.slf4j.Slf4j;

@Slf4j
@SpringBootApplication
public class JsonLogApplication {

    public static void main(String[] args) {
        SpringApplication.run(JsonLogApplication.class, args);
        MDC.put("id", AppConstant.PROJECT_NAME_PREFIX + "_" + AppConstant.MARKET_CODE + "_" + AppConstant.PARAM_TYPE);
        log.info("---------- Spring Application started successfully ----------");
        log.debug("This is a debug message.");
        log.info("This is an info message.");
        log.warn("This is a warn message.");
        log.error("This is an error message.");
        log.info("---------- Spring Application ended successfully ----------");
    }
}

--这将在logs目录中创建两个日志文件。

1. application-text.log看起来就像这个

[INFO ] 2020-09-11 22:36:13.627 [main] DEMO_IND_PARAM c.a.JsonLogApplication - ---------- Spring Application started successfully ----------
[INFO ] 2020-09-11 22:36:13.630 [main] DEMO_IND_PARAM c.a.JsonLogApplication - This is an info message.
[WARN ] 2020-09-11 22:36:13.630 [main] DEMO_IND_PARAM c.a.JsonLogApplication - This is a warn message.
[ERROR] 2020-09-11 22:36:13.631 [main] DEMO_IND_PARAM c.a.JsonLogApplication - This is an error message.
[INFO ] 2020-09-11 22:36:13.631 [main] DEMO_IND_PARAM c.a.JsonLogApplication - ---------- Spring Application ended successfully ----------

1. application-json.log看起来就像这个

{"@timestamp":"2020-09-11T22:36:13.627+05:30","@version":"1","message":"---------- Spring Application started successfully ----------","logger_name":"com.altafjava.JsonLogApplication","thread_name":"main","level":"INFO","level_value":20000,"id":"DEMO_IND_PARAM"}
{"@timestamp":"2020-09-11T22:36:13.630+05:30","@version":"1","message":"This is an info message.","logger_name":"com.altafjava.JsonLogApplication","thread_name":"main","level":"INFO","level_value":20000,"id":"DEMO_IND_PARAM"}
{"@timestamp":"2020-09-11T22:36:13.630+05:30","@version":"1","message":"This is a warn message.","logger_name":"com.altafjava.JsonLogApplication","thread_name":"main","level":"WARN","level_value":30000,"id":"DEMO_IND_PARAM"}
{"@timestamp":"2020-09-11T22:36:13.631+05:30","@version":"1","message":"This is an error message.","logger_name":"com.altafjava.JsonLogApplication","thread_name":"main","level":"ERROR","level_value":40000,"id":"DEMO_IND_PARAM"}
{"@timestamp":"2020-09-11T22:36:13.631+05:30","@version":"1","message":"---------- Spring Application ended successfully ----------","logger_name":"com.altafjava.JsonLogApplication","thread_name":"main","level":"INFO","level_value":20000,"id":"DEMO_IND_PARAM"}

注意:这里@Slf4j是一个Lombok注释。这意味着在不创建LoggerFactory的情况下，您可以直接使用日志方法。因为您需要在IDE中安装Lombok &在pom.xml中添加一个依赖项

如果您需要一个演示项目，请访问https://github.com/altafjava/json-log

Answer 2

您可以在logback.xml中为json和文本格式配置如下所示的片段。

    <appender name="json" class="ch.qos.logback.core.ConsoleAppender">
    <layout class="ch.qos.logback.contrib.json.classic.JsonLayout">
        <jsonFormatter
            class="ch.qos.logback.contrib.jackson.JacksonJsonFormatter">
            <prettyPrint>true</prettyPrint>
        </jsonFormatter>
        <timestampFormat>yyyy-MM-dd' 'HH:mm:ss.SSS</timestampFormat>
    </layout>
</appender>




<appender name="FILE" class="ch.qos.logback.core.FileAppender">
        <file>logfile.log</file>
        <append>true</append>
        <encoder>
            <pattern>%-4relative [%thread] %-5level %logger{35} - %msg %n</pattern>
        </encoder>
    </appender>

只需更改这里的类，就可以将其中一个打印为consoleAppender，另一个打印为您可以同时指向控制台的文件。