SpringBoot日志打印实践过程
作者：沉河不浮
文章介绍了如何在SpringBoot项目中使用Logback实现日志打印,并通过自定义日志打印工具类和日志分文件打印来提高日志排查和监控的效率
背景
在项目当中，我们经常需要打印一些日志埋点信息，这些日志埋点信息，在后续软件的运维、稳定性建设中发挥了巨大的作用：
- 问题追踪：通过埋点日志中的关键信息，帮助定位系统异常原因
- 系统监控：通过日志，监控系统的运行情况，包括性能指标、访问频率、错误等
- 数据分析：分析用户行为、系统性能和业务趋势等
- 调试：通过查看日志，帮助开发人员了解程序在执行过程中的状态和行为
SpringBoot整合Logback实现日志打印
SpringBoot默认使用Slf4j作为日志门面，并集成Logback作为日志实现。
要在springboot中实现日志打印，只需要引入下列依赖：
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
</dependency>然后在配置文件中，配置对应的日志级别：
logging:
level:
root: INFO对某些特定的包，需要指定日志级别，则配置如下：
logging:
level:
com.example.demo: DEBUG最后，我们创建logback-spring.xml，来自定义日志的配置信息，包括日志输出文件、日志格式等
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<property name="LOG_PATH" value="logs"/>
<property name="LOG_FILE" value="${LOG_PATH}/spring-boot-logger.log"/>
<appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss} - %msg%n</pattern>
</encoder>
</appender>
<appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>common.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${LOG_PATH}/spring-boot-logger.%d{yyyy-MM-dd}.log</fileNamePattern>
<maxHistory>30</maxHistory>
</rollingPolicy>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss} - %msg%n</pattern>
</encoder>
</appender>
<root level="INFO">
<appender-ref ref="CONSOLE"/>
<appender-ref ref="FILE"/>
</root>
</configuration>然后，我们在需要打印日志的类，加上Slf4j注解，然后使用log来打印日志信息即可，如下代码所示：
package com.yang.web.controller;
import com.yang.api.common.ResultT;
import com.yang.api.common.command.RegisterCommand;
import com.yang.api.common.dto.UserDTO;
import com.yang.api.common.facade.UserFacade;
import com.yang.web.request.RegisterRequest;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
@RestController
@RequestMapping(value = "/user")
@Slf4j
public class UserController {
@Autowired
private UserFacade userFacade;
@GetMapping(value = "/{id}")
public ResultT<UserDTO> queryById(@PathVariable("id") Integer id) {
log.info("queryById===========");
return userFacade.getById(id);
}
@PostMapping(value = "/register")
public ResultT<String> register(@RequestBody RegisterRequest registerRequest) {
RegisterCommand registerCommand = convert2RegisterCommand(registerRequest);
return userFacade.register2(registerCommand);
}
private RegisterCommand convert2RegisterCommand(RegisterRequest registerRequest) {
RegisterCommand registerCommand = new RegisterCommand();
registerCommand.setLoginId(registerRequest.getLoginId());
registerCommand.setEmail(registerRequest.getEmail());
registerCommand.setPassword(registerRequest.getPassword());
registerCommand.setExtendMaps(registerRequest.getExtendMaps());
return registerCommand;
}
}然后访问queryById，打印结果如下：
日志打印工具类
在logback-spring.xml中，我们虽然能配置日志打印的格式，但是不够灵活，因此，我们可以添加一个日志打印工具类，通过该工具类，来自定义项目中的日志打印格式，以方便后续更好地通过日志排查、定位问题。
首先创建一个日志打印抽象类，定义日志打印的格式：
package com.yang.core.infrastructure.log;
import org.apache.commons.lang3.StringUtils;
import org.springframework.util.CollectionUtils;
import java.util.ArrayList;
import java.util.List;
public abstract class AbstractLogPrinter {
protected String bizCode;
protected List<String> params = new ArrayList<>();
protected String msg;
protected Throwable e;
public AbstractLogPrinter addBizCode(String bizCode) {
this.bizCode = bizCode;
return this;
}
public AbstractLogPrinter addMsg(String msg) {
this.msg = msg;
return this;
}
public AbstractLogPrinter addParam(String key, String value) {
this.params.add(key);
this.params.add(value);
return this;
}
public AbstractLogPrinter addThrowable(Throwable e) {
this.e = e;
return this;
}
public abstract void printBizLog();
public abstract void printErrorLog();
public abstract String getSeparator();
public String commonContent() {
StringBuilder stringBuilder = new StringBuilder();
String separator = getSeparator();
stringBuilder.append("bizCode").append(":")
.append(this.bizCode).append(separator);
if (!CollectionUtils.isEmpty(params)) {
for (int i = 0; i < params.size(); i += 2) {
stringBuilder.append(params.get(i))
.append(":")
.append(params.get(i + 1))
.append(separator);
}
}
if (StringUtils.isNotEmpty(msg)) {
stringBuilder.append("msg").append(":")
.append(msg).append(separator);
}
return stringBuilder.toString();
}
}
然后创建日志打印实现类，在实现类中，定制实现日志打印的级别、分隔符等内容
package com.yang.core.infrastructure.log;
import lombok.extern.slf4j.Slf4j;
@Slf4j
public class PlatformLogPrinter extends AbstractLogPrinter {
public void printBizLog() {
log.info(commonContent());
}
public void printErrorLog() {
if (e != null) {
log.error(commonContent(), e);
} else {
log.error(commonContent());
}
}
@Override
public String getSeparator() {
return "<|>";
}
}同时，为了方便打印日志，创建一个日志打印创建者
package com.yang.core.infrastructure.log;
public class PlatformLogger {
public static AbstractLogPrinter build() {
return new PlatformLogPrinter();
}
}上述内容准备完毕后，我们在controller中，使用PlatformLogger来打印日志，修改后的代码如下：
package com.yang.web.controller;
import com.yang.api.common.ResultT;
import com.yang.api.common.command.RegisterCommand;
import com.yang.api.common.dto.UserDTO;
import com.yang.api.common.facade.UserFacade;
import com.yang.core.infrastructure.log.PlatformLogger;
import com.yang.web.request.RegisterRequest;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
@RestController
@RequestMapping(value = "/user")
public class UserController {
@Autowired
private UserFacade userFacade;
@GetMapping(value = "/{id}")
public ResultT<UserDTO> queryById(@PathVariable("id") Integer id) {
PlatformLogger.build()
.addBizCode("queryById")
.addParam("id", id.toString())
.addMsg("query by id")
.printBizLog();
return userFacade.getById(id);
}
@GetMapping(value = "/error/{id}")
public ResultT testError(@PathVariable("id") Integer id) {
try {
int i = 1 / 0;
} catch (Throwable t) {
PlatformLogger.build()
.addBizCode("testError")
.addParam("id", id.toString())
.addMsg("test error print")
.addThrowable(t)
.printErrorLog();
}
return ResultT.fail();
}
@PostMapping(value = "/register")
public ResultT<String> register(@RequestBody RegisterRequest registerRequest) {
RegisterCommand registerCommand = convert2RegisterCommand(registerRequest);
return userFacade.register2(registerCommand);
}
private RegisterCommand convert2RegisterCommand(RegisterRequest registerRequest) {
RegisterCommand registerCommand = new RegisterCommand();
registerCommand.setLoginId(registerRequest.getLoginId());
registerCommand.setEmail(registerRequest.getEmail());
registerCommand.setPassword(registerRequest.getPassword());
registerCommand.setExtendMaps(registerRequest.getExtendMaps());
return registerCommand;
}
}
启动项目，分别访问queryById和testError，打印日志内容如下：
日志分文件打印
一般情况下，我们的项目会分为不同的模块，每一个模块承担不同的职责，比如bussiness模块，主要是负责业务逻辑代码的实现，业务逻辑编排等；web模块主要负责http请求的接收，参数的校验，入参转化为业务层入参等；而core模块主要负责基础能力实现，比如持久化数据库、领域服务实现等。
对于不同的模块，我们希望将日志输出到不同的文件当中，从而协助我们后续定位问题以及建设不同模块下的监控，包括基础服务监控、业务成功率监控等。
因此，我们在不同的模块下，分别实现不同的日志打印工具类：
package com.yang.web.log;
import com.yang.core.infrastructure.log.AbstractLogPrinter;
public class WebLogger {
public static AbstractLogPrinter build() {
return new WebLogPrinter();
}
}
package com.yang.web.log;
import com.yang.core.infrastructure.log.AbstractLogPrinter;
import lombok.extern.slf4j.Slf4j;
@Slf4j
public class WebLogPrinter extends AbstractLogPrinter {
@Override
public void printBizLog() {
log.info(commonContent());
}
@Override
public void printErrorLog() {
if (this.e != null) {
log.error(commonContent(), e);
} else {
log.error(commonContent());
}
}
@Override
public String getSeparator() {
return "<|>";
}
}
package com.yang.business.log;
public class BusinessLogger {
public static BusinessLogPrinter build() {
return new BusinessLogPrinter();
}
}
package com.yang.business.log;
import com.yang.core.infrastructure.log.AbstractLogPrinter;
import lombok.extern.slf4j.Slf4j;
@Slf4j
public class BusinessLogPrinter extends AbstractLogPrinter {
@Override
public void printBizLog() {
log.info(commonContent());
}
@Override
public void printErrorLog() {
if (this.e != null) {
log.error(commonContent(), e);
} else {
log.error(commonContent());
}
}
@Override
public String getSeparator() {
return "<|>";
}
}
然后我们修改logback-spring.xml文件，将不同的日志打印工具类，输出到不同的日志文件中
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<property name="LOG_PATH" value="logs"/>
<property name="LOG_FILE" value="${LOG_PATH}/spring-boot-logger.log"/>
<appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss} - %msg%n</pattern>
</encoder>
</appender>
<appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>common.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${LOG_PATH}/spring-boot-logger.%d{yyyy-MM-dd}.log</fileNamePattern>
<maxHistory>30</maxHistory>
</rollingPolicy>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss} - %msg%n</pattern>
</encoder>
</appender>
<appender name="PLATFORM_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>platform.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${LOG_PATH}/platform-logger.%d{yyyy-MM-dd}.log</fileNamePattern>
<maxHistory>30</maxHistory>
</rollingPolicy>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss} - %msg%n</pattern>
</encoder>
</appender>
<appender name="BUSINESS_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>business.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${LOG_PATH}/business-logger.%d{yyyy-MM-dd}.log</fileNamePattern>
<maxHistory>30</maxHistory>
</rollingPolicy>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss} - %msg%n</pattern>
</encoder>
</appender>
<appender name="WEB_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>web.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${LOG_PATH}/web-logger.%d{yyyy-MM-dd}.log</fileNamePattern>
<maxHistory>30</maxHistory>
</rollingPolicy>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss} - %msg%n</pattern>
</encoder>
</appender>
<root level="INFO">
<appender-ref ref="CONSOLE"/>
<appender-ref ref="FILE"/>
</root>
<!-- 工具类PlatformLogPrinter的logger -->
<logger name="com.yang.core.infrastructure.log.PlatformLogPrinter" level="INFO" additivity="false">
<appender-ref ref="PLATFORM_FILE" />
</logger>
<!-- 工具类BusinessLogPrinter的logger -->
<logger name="com.yang.business.log.BusinessLogPrinter" level="INFO" additivity="false">
<appender-ref ref="BUSINESS_FILE" />
</logger>
<!-- 工具类WebLogPrinter的logger -->
<logger name="com.yang.web.log.WebLogPrinter" level="INFO" additivity="false">
<appender-ref ref="WEB_FILE" />
</logger>
</configuration>最后，分别在web模块、business模块和core模块下，添加埋点日志
// WEB模块
@GetMapping(value = "/{id}")
public ResultT<UserDTO> queryById(@PathVariable("id") Integer id) {
WebLogger.build()
.addBizCode("userController_queryById")
.addParam("id", id.toString())
.addMsg("query by id")
.printBizLog();
return userFacade.getById(id);
}
// Business模块
@Override
public ResultT<UserDTO> getById(Integer id) {
UserQueryDomainRequest userQueryDomainRequest = new UserQueryDomainRequest.UserQueryDomainRequestBuilder()
.queryMessage(id.toString())
.userQueryType(UserQueryType.ID)
.build();
UserQueryDomainResponse userQueryDomainResponse = userDomainService.query(userQueryDomainRequest);
List<UserAccount> userAccountList = userQueryDomainResponse.getUserAccountList();
UserDTO userDTO = null;
if (!CollectionUtils.isEmpty(userAccountList)) {
UserAccount userAccount = userAccountList.get(0);
userDTO = userDTOConvertor.convert2DTO(userAccount);
}
BusinessLogger.build()
.addBizCode("userFacade_getById")
.addParam("id", id.toString())
.addParam("userDTO", JSONObject.toJSONString(userDTO))
.addMsg("get by id")
.printBizLog();
return ResultT.success(userDTO);
}
// core模块
public UserQueryDomainResponse query(UserQueryDomainRequest userQueryDomainRequest) {
UserQueryType userQueryType = userQueryDomainRequest.getUserQueryType();
UserDO userDO = null;
switch (userQueryType) {
case ID:
userDO = queryById(Integer.valueOf(userQueryDomainRequest.getQueryMessage()));
break;
case EMAIL:
userDO = queryByEmail(userQueryDomainRequest.getQueryMessage());
break;
case LOGIN_ID:
userDO = queryByLoginId(userQueryDomainRequest.getQueryMessage());
break;
}
if (userDO == null) {
return new UserQueryDomainResponse();
}
UserAccount userAccount = new UserAccount();
userAccount.setId(userDO.getId());
userAccount.setLoginId(userDO.getLoginId());
userAccount.setEmail(userDO.getEmail());
userAccount.setFeatureMap(FeatureUtils.convert2FeatureMap(userDO.getFeatures()));
userAccount.setCreateTime(userDO.getCreateTime());
userAccount.setUpdateTime(userDO.getUpdateTime());
UserQueryDomainResponse userQueryDomainResponse = new UserQueryDomainResponse();
List<UserAccount> userAccounts = new ArrayList<>();
userAccounts.add(userAccount);
userQueryDomainResponse.setUserAccountList(userAccounts);
PlatformLogger.build()
.addBizCode("userDomainService_query")
.addParam("queryMsg", userQueryDomainRequest.getQueryMessage())
.addParam("queryType", userQueryDomainRequest.getUserQueryType().name())
.printBizLog();
return userQueryDomainResponse;
}启动项目，访问queryById接口，可以看到在web.log，business.log和platform.log下分别打印了不同的日志信息
总结
以上为个人经验，希望能给大家一个参考，也希望大家多多支持脚本之家。