java - 如何使用 logback 以文本和 json 格式打印 Spring Boot 日志？

Question

对于日志记录，我们使用 Logback。目前我们使用 Splunk 来查看 Spring Boot 日志。根据项目要求，我们需要转向 Kibana。首先，我们应该以 JSON 格式登录，以便 Kibana 可以轻松处理它。目前我们没有用 Kibana 替换 Splunk，但是当与 Kibana 集成成功时，我们可以逐渐在所有项目中替换 Splunk。
因此，根据要求，我们需要现有日志，即文本日志，但出于研发目的，我们也需要 JSON 日志。

Answer 1

这很简单。您只需要添加 logstash-logback-encoder依赖于 pom.xml文件并在您的 logback.xml 中写入一些配置文件。请按照以下步骤来满足您的要求。
第一步:添加 logstash-logback-encoder依赖于 pom.xml .

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

第二步:创建 logback.xml里面的文件 src/main/resources/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>

第三步:现在你可以在类里面的任何地方使用 log 语句。假设您在 Spring Boot 的主类中使用。

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 ----------");
    }
}

This will create two log files inside the logs directory.

application-text.log看起来像这样

[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 ----------

application-json.log看起来像这样

{"@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 Lombok 注释。这意味着无需创建 LoggerFactory 就可以直接使用日志方法。您需要在 IDE 中安装 Lombok 并在 pom.xml 中添加依赖项
如果您需要演示项目，请访问 https://github.com/altafjava/json-log