前言

ELK即Elasticsearch、Logstash、Kibana,组合起来可以搭建线上日志系统，本文主要讲解使用ELK来收集SpringBoot应用产生的日志。

ELK中各个服务的作用

Elasticsearch:用于存储收集到的日志信息；

Logstash:用于收集日志，SpringBoot应用整合了Logstash以后会把日志发送给Logstash,Logstash再把日志转发给Elasticsearch；

Kibana:通过Web端的可视化界面来查看日志。

正文

1.根据SpringBoot版本查看对应的ES、LogStash、Kibana版本

(1) SpringBoot使用 spring-boot-dependencies方式依赖es

           <!-- springboot版本-->
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
                <version>${spring-boot.version}</version>
            </dependency>

(2)SpringBoot使用 spring-boot-starter-parent 方式依赖es

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
    </dependency>

(3) 刷新maven后可以看到当前项目对应的SpringBoot版本

2.使用Docker Compose 搭建ELK环境

(1) 根据项目依赖的版本pull对应的版本，注意 ELK版本必须完全一致

docker pull elasticsearch:7.12.1
docker pull logstash:7.12.1
docker pull kibana:7.12.1

(2) 创建一个存放logstash配置的目录并上传配置文件

创建配置文件存放目录

mkdir /mydata/elk/logstash
mkdir /mydata/elk/es
mkdir /mydata/elk/kibana
cd /mydata/elk/logstash
vim logstash-springboot.conf

logstash-springboot.conf文件内容

input {
  tcp {
    mode => "server"
    host => "0.0.0.0"
    port => 4560
    codec => json_lines
    type => "debug"
  }
  tcp {
    mode => "server"
    host => "0.0.0.0"
    port => 4561
    codec => json_lines
    type => "error"
  }
  tcp {
    mode => "server"
    host => "0.0.0.0"
    port => 4562
    codec => json_lines
    type => "business"
  }
  tcp {
    mode => "server"
    host => "0.0.0.0"
    port => 4563
    codec => json_lines
    type => "record"
  }
}
filter{
  if [type] == "record" {
    mutate {
      remove_field => "port"
      remove_field => "host"
      remove_field => "@version"
    }
    json {
      source => "message"
      remove_field => ["message"]
    }
  }
}
output {
  elasticsearch {
    hosts => "es:9200"
    index => "soboot-%{type}-%{+YYYY.MM.dd}"
  }
}

(3)使用docker-compose.yml脚本启动ELK服务

cd /mydata/elk
vim docker-compose.yml

docker-compose.yml内容

version: '3'
services:
  elasticsearch:
    image: elasticsearch:7.12.1
    container_name: elasticsearch
    environment:
      - "cluster.name=elasticsearch" #设置集群名称为elasticsearch
      - "discovery.type=single-node" #以单一节点模式启动
      - "ES_JAVA_OPTS=-Xms512m -Xmx512m" #设置使用jvm内存大小
    volumes:
      - /mydata/elk/es/plugins:/usr/share/elasticsearch/plugins #插件文件挂载
      - /mydata/elk/es/data:/usr/share/elasticsearch/data #数据文件挂载
    ports:
      - 9200:9200
      - 9300:9300
  kibana:
    image: kibana:7.12.1
    container_name: kibana
    links:
      - elasticsearch:es #可以用es这个域名访问elasticsearch服务
    depends_on:
      - elasticsearch #kibana在elasticsearch启动之后再启动
    environment:
      - "elasticsearch.hosts=http://es:9200" #设置访问elasticsearch的地址
    ports:
      - 5601:5601
  logstash:
    image: logstash:7.12.1
    container_name: logstash
    volumes:
      - /mydata/elk/logstash/logstash-springboot.conf:/usr/share/logstash/pipeline/logstash.conf #挂载logstash的配置文件
    depends_on:
      - elasticsearch #kibana在elasticsearch启动之后再启动
    links:
      - elasticsearch:es #可以用es这个域名访问elasticsearch服务
    ports:
      - 4560:4560
      - 4561:4561
      - 4562:4562
      - 4563:4563

(4) 执行docker-compose命令运行elk

docker-compose up -d

注意：Elasticsearch启动可能需要好几分钟，要耐心等待。

(5)启动完成后在logstash中安装json_lines插件

# 进入logstash容器
docker exec -it logstash /bin/bash
# 进入bin目录
cd /bin/
# 安装插件
logstash-plugin install logstash-codec-json_lines
# 退出容器
exit
# 重启logstash服务
docker restart logstash

6) 访问kibana

注意：关闭防火墙或配置安全组

访问地址：http://服务器IP:5601

3.SpringBoot应用集成ELK

(1) 在pom.xml中添加logstash-logback-encoder依赖

<!--集成logstash-->
<dependency>
    <groupId>net.logstash.logback</groupId>
    <artifactId>logstash-logback-encoder</artifactId>
    <version>5.3</version>
</dependency>

(2) 添加配置文件logback-spring.xml让logback的日志输出到logstash

注意appender节点下的destination需要改成你自己的logstash服务地址，比如：10.12.13.14:4560

logback-spring.xml 内容

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration>
<configuration>
    <!--引用默认日志配置-->
    <include resource="org/springframework/boot/logging/logback/defaults.xml"/>
    <!--使用默认的控制台日志输出实现-->
    <include resource="org/springframework/boot/logging/logback/console-appender.xml"/>
    <!--应用名称-->
    <springProperty scope="context" name="APP_NAME" source="spring.application.name" defaultValue="springBoot"/>
    <!--日志文件保存路径-->
<!--    <property name="LOG_FILE_PATH" value="${LOG_FILE:-${LOG_PATH:-${LOG_TEMP:-${java.io.tmpdir:-/tmp}}}/logs}"/>-->
    <!--LogStash访问host-->
    <springProperty name="LOG_STASH_HOST" scope="context" source="logstash.host" defaultValue="10.12.13.14"/>
    <!--DEBUG日志输出到文件-->
    <appender name="FILE_DEBUG"
              class="ch.qos.logback.core.rolling.RollingFileAppender">
        <!--输出DEBUG以上级别日志-->
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>DEBUG</level>
        </filter>
        <encoder>
            <!--设置为默认的文件日志格式-->
            <pattern>${FILE_LOG_PATTERN}</pattern>
            <charset>UTF-8</charset>
        </encoder>
        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
            <!--设置文件命名格式-->
            <fileNamePattern>${LOG_FILE_PATH}/debug/${APP_NAME}-%d{yyyy-MM-dd}-%i.log</fileNamePattern>
            <!--设置日志文件大小，超过就重新生成文件，默认10M-->
            <maxFileSize>${LOG_FILE_MAX_SIZE:-10MB}</maxFileSize>
            <!--日志文件保留天数，默认30天-->
            <maxHistory>${LOG_FILE_MAX_HISTORY:-30}</maxHistory>
        </rollingPolicy>
    </appender>
    <!--ERROR日志输出到文件-->
    <appender name="FILE_ERROR"
              class="ch.qos.logback.core.rolling.RollingFileAppender">
        <!--只输出ERROR级别的日志-->
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>ERROR</level>
            <onMatch>ACCEPT</onMatch>
            <onMismatch>DENY</onMismatch>
        </filter>
        <encoder>
            <!--设置为默认的文件日志格式-->
            <pattern>${FILE_LOG_PATTERN}</pattern>
            <charset>UTF-8</charset>
        </encoder>
        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
            <!--设置文件命名格式-->
            <fileNamePattern>${LOG_FILE_PATH}/error/${APP_NAME}-%d{yyyy-MM-dd}-%i.log</fileNamePattern>
            <!--设置日志文件大小，超过就重新生成文件，默认10M-->
            <maxFileSize>${LOG_FILE_MAX_SIZE:-10MB}</maxFileSize>
            <!--日志文件保留天数，默认30天-->
            <maxHistory>${LOG_FILE_MAX_HISTORY:-30}</maxHistory>
        </rollingPolicy>
    </appender>
    <!-- 控制台异步实时输出 -->
    <appender name="ASYNC_CONSOLE_APPENDER" class="ch.qos.logback.classic.AsyncAppender">
        <!-- 不丢失日志.默认的,如果队列的80%已满,则会丢弃TRACT、DEBUG、INFO级别的日志 -->
        <discardingThreshold>0</discardingThreshold>
        <!-- 更改默认的队列的深度,该值会影响性能.默认值为256 -->
        <queueSize>256</queueSize>
        <!-- 添加附加的appender,最多只能添加一个 -->
        <appender-ref ref="FILE_DEBUG"/>
    </appender>
    <!--DEBUG日志输出到LogStash-->
    <appender name="LOG_STASH_DEBUG" class="net.logstash.logback.appender.LogstashTcpSocketAppender">
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>DEBUG</level>
        </filter>
        <destination>${LOG_STASH_HOST}:4560</destination>
        <encoder charset="UTF-8" class="net.logstash.logback.encoder.LoggingEventCompositeJsonEncoder">
            <providers>
                <timestamp>
                    <timeZone>Asia/Shanghai</timeZone>
                </timestamp>
                <!--自定义日志输出格式-->
                <pattern>
                    <pattern>
                        {
                        "project": "soboot",
                        "level": "%level",
                        "service": "${APP_NAME:-}",
                        "pid": "${PID:-}",
                        "thread": "%thread",
                        "class": "%logger",
                        "message": "%message",
                        "stack_trace": "%exception{20}"
                        }
                    </pattern>
                </pattern>
            </providers>
        </encoder>
    </appender>
    <!--ERROR日志输出到LogStash-->
    <appender name="LOG_STASH_ERROR" class="net.logstash.logback.appender.LogstashTcpSocketAppender">
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>ERROR</level>
            <onMatch>ACCEPT</onMatch>
            <onMismatch>DENY</onMismatch>
        </filter>
        <destination>${LOG_STASH_HOST}:4561</destination>
        <encoder charset="UTF-8" class="net.logstash.logback.encoder.LoggingEventCompositeJsonEncoder">
            <providers>
                <timestamp>
                    <timeZone>Asia/Shanghai</timeZone>
                </timestamp>
                <!--自定义日志输出格式-->
                <pattern>
                    <pattern>
                        {
                        "project": "soboot",
                        "level": "%level",
                        "service": "${APP_NAME:-}",
                        "pid": "${PID:-}",
                        "thread": "%thread",
                        "class": "%logger",
                        "message": "%message",
                        "stack_trace": "%exception{20}"
                        }
                    </pattern>
                </pattern>
            </providers>
        </encoder>
    </appender>
    <!--业务日志输出到LogStash-->
    <appender name="LOG_STASH_BUSINESS" class="net.logstash.logback.appender.LogstashTcpSocketAppender">
        <destination>${LOG_STASH_HOST}:4562</destination>
        <encoder charset="UTF-8" class="net.logstash.logback.encoder.LoggingEventCompositeJsonEncoder">
            <providers>
                <timestamp>
                    <timeZone>Asia/Shanghai</timeZone>
                </timestamp>
                <!--自定义日志输出格式-->
                <pattern>
                    <pattern>
                        {
                        "project": "soboot",
                        "level": "%level",
                        "service": "${APP_NAME:-}",
                        "pid": "${PID:-}",
                        "thread": "%thread",
                        "class": "%logger",
                        "message": "%message",
                        "stack_trace": "%exception{20}"
                        }
                    </pattern>
                </pattern>
            </providers>
        </encoder>
    </appender>
    <!--接口访问记录日志输出到LogStash-->
    <appender name="LOG_STASH_RECORD" class="net.logstash.logback.appender.LogstashTcpSocketAppender">
        <destination>${LOG_STASH_HOST}:4563</destination>
        <encoder charset="UTF-8" class="net.logstash.logback.encoder.LoggingEventCompositeJsonEncoder">
            <providers>
                <timestamp>
                    <timeZone>Asia/Shanghai</timeZone>
                </timestamp>
                <!--自定义日志输出格式-->
                <pattern>
                    <pattern>
                        {
                        "project": "soboot",
                        "level": "%level",
                        "service": "${APP_NAME:-}",
                        "class": "%logger",
                        "message": "%message"
                        }
                    </pattern>
                </pattern>
            </providers>
        </encoder>
    </appender>
    <!--控制框架输出日志-->
    <logger name="org.slf4j" level="INFO"/>
    <logger name="springfox" level="INFO"/>
    <logger name="io.swagger" level="INFO"/>
    <logger name="org.springframework" level="INFO"/>
    <logger name="org.hibernate.validator" level="INFO"/>
    <root level="DEBUG">
        <appender-ref ref="CONSOLE"/>
        <appender-ref ref="FILE_DEBUG"/>
        <appender-ref ref="FILE_ERROR"/>
        <appender-ref ref="LOG_STASH_RECORD"/>
        <appender-ref ref="LOG_STASH_DEBUG"/>
        <appender-ref ref="LOG_STASH_ERROR"/>
    </root>
    <logger name="com.soboot.common.log.aspect.WebLogAspect" level="DEBUG">
        <appender-ref ref="LOG_STASH_RECORD"/>
    </logger>
    <logger name="com.soboot" level="DEBUG">
        <appender-ref ref="LOG_STASH_BUSINESS"/>
    </logger>
</configuration>

(3)编写统一日志处理切面

WebLog.java内容

package com.soboot.common.log.domain;
import lombok.Data;
import lombok.EqualsAndHashCode;
/**
 * Controller层的日志封装类
 * Created by liu on 2022/03/15.
 * @author liuy
 */
@Data
@EqualsAndHashCode(callSuper = false)
public class WebLog {
    /**
     * 操作描述
     */
    private String description;
    /**
     * 操作用户
     */
    private String username;
    /**
     * 操作时间
     */
    private Long startTime;
    /**
     * 消耗时间
     */
    private Integer spendTime;
    /**
     * 根路径
     */
    private String basePath;
    /**
     * URI
     */
    private String uri;
    /**
     * URL
     */
    private String url;
    /**
     * 请求类型
     */
    private String method;
    /**
     * IP地址
     */
    private String ip;
    /**
     * 请求参数
     */
    private Object parameter;
    /**
     * 返回结果
     */
    private Object result;
}

WebLogAspect.java 内容

package com.soboot.common.log.aspect;
import cn.hutool.core.util.StrUtil;
import cn.hutool.core.util.URLUtil;
import cn.hutool.json.JSONUtil;
import com.soboot.common.log.domain.WebLog;
import io.swagger.annotations.ApiOperation;
import net.logstash.logback.marker.Markers;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.*;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.servlet.http.HttpServletRequest;
import java.lang.reflect.Method;
import java.lang.reflect.Parameter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
 /**
 * 统一日志处理切面
 * Created by liu on 2022/03/15.
 * @author liuy
 */
@Aspect
@Component
@Order(1)
public class WebLogAspect {
    private static final Logger LOGGER = LoggerFactory.getLogger(WebLogAspect.class);
    @Pointcut("execution(public * com.soboot.controller.*.*(..))||execution(public * com.soboot.*.controller.*.*(..))")
    public void webLog() {
    }
    @Before("webLog()")
    public void doBefore(JoinPoint joinPoint) throws Throwable {
    }
    @AfterReturning(value = "webLog()", returning = "ret")
    public void doAfterReturning(Object ret) throws Throwable {
    }
    @Around("webLog()")
    public Object doAround(ProceedingJoinPoint joinPoint) throws Throwable {
        long startTime = System.currentTimeMillis();
        //获取当前请求对象
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        HttpServletRequest request = attributes.getRequest();
        //记录请求信息(通过Logstash传入Elasticsearch)
        WebLog webLog = new WebLog();
        Object result = joinPoint.proceed();
        Signature signature = joinPoint.getSignature();
        MethodSignature methodSignature = (MethodSignature) signature;
        Method method = methodSignature.getMethod();
        if (method.isAnnotationPresent(ApiOperation.class)) {
            ApiOperation log = method.getAnnotation(ApiOperation.class);
            webLog.setDescription(log.value());
        }
        long endTime = System.currentTimeMillis();
        String urlStr = request.getRequestURL().toString();
        webLog.setBasePath(StrUtil.removeSuffix(urlStr, URLUtil.url(urlStr).getPath()));
        webLog.setUsername(request.getRemoteUser());
        webLog.setIp(request.getRemoteAddr());
        webLog.setMethod(request.getMethod());
        webLog.setParameter(getParameter(method, joinPoint.getArgs()));
        webLog.setResult(result);
        webLog.setSpendTime((int) (endTime - startTime));
        webLog.setStartTime(startTime);
        webLog.setUri(request.getRequestURI());
        webLog.setUrl(request.getRequestURL().toString());
        Map<String,Object> logMap = new HashMap<>();
        logMap.put("url",webLog.getUrl());
        logMap.put("method",webLog.getMethod());
        logMap.put("parameter",webLog.getParameter());
        logMap.put("spendTime",webLog.getSpendTime());
        logMap.put("description",webLog.getDescription());
        LOGGER.info(Markers.appendEntries(logMap), JSONUtil.parse(webLog).toString());
        return result;
    }
    /**
     * 根据方法和传入的参数获取请求参数
     */
    private Object getParameter(Method method, Object[] args) {
        List<Object> argList = new ArrayList<>();
        Parameter[] parameters = method.getParameters();
        for (int i = 0; i < parameters.length; i++) {
            //将RequestBody注解修饰的参数作为请求参数
            RequestBody requestBody = parameters[i].getAnnotation(RequestBody.class);
            if (requestBody != null) {
                argList.add(args[i]);
            }
            //将RequestParam注解修饰的参数作为请求参数
            RequestParam requestParam = parameters[i].getAnnotation(RequestParam.class);
            if (requestParam != null) {
                Map<String, Object> map = new HashMap<>();
                String key = parameters[i].getName();
                if (!StringUtils.isEmpty(requestParam.value())) {
                    key = requestParam.value();
                }
                map.put(key, args[i]);
                argList.add(map);
            }
        }
        if (argList.size() == 0) {
            return null;
        } else if (argList.size() == 1) {
            return argList.get(0);
        } else {
            return argList;
        }
    }
}

(4) 添加es、logstash yml配置

yml配置

spring: 
  data:
    elasticsearch:
      repositories:
        enabled: true
  elasticsearch:
    rest:
      # es部署的服务器IP:9200
      uris: 10.12.13.14:9200
logging:
  level:
    root: info
    com.soboot: debug
logstash:
  # logstash部署的服务器IP
  host: 10.12.13.14