log4j2、log4j和logback动态修改日志级别工具类

工作中，在排查线上问题时，有以下场景在不重新部署或重启服务的情况下，需要动态调整线上日志级别

1、线上有些日志打印过多干扰有用的日志，需要动态修改线上日志记录器的打印日志级别，调高一些日志级别，打印出更少的干扰日志

2、由于线上日志级别打印的相关有用日志太少，需要动态修改线上日志记录器的打印日志级别，调低一些日志级别，打印出更多的有用日志

   本文的两个工具类使用的版本如下：

----------------logback---------------------

 <dependency>
   <groupId>ch.qos.logback</groupId>
   <artifactId>logback-core</artifactId>
   <version>1.1.8</version>
</dependency>
-----------------log4j2--------------------
<dependency>

   <groupId>org.springframework.boot</groupId>

   <artifactId>spring-boot-starter-log4j2</artifactId>

   <version>1.5.12.RELEASE</version>

</dependency>
<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j</artifactId>
    <version>2.7</version>
 </dependency>

-----------------Log4j2Controller-------------------------

@Api(tags = "Log4j2Controller",description = "Log4j2控制类")
@RestController
@RequestMapping("/log/control")
public class Log4j2Controller {
    private static final Logger logger = LoggerFactory.getLogger(Log4j2Controller.class);

    @RequestMapping(value = "/getLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public Level getLoglevel(@RequestParam(value="package") String packageName) throws Exception {//package 指定修改日志级别的包路径 ，如 org.mybatis
           logger.info("getLoglevel packageName is {}",packageName);
           LoggerContext ctx = (LoggerContext) LogManager.getContext(false);
          return  ctx.getLogger(packageName).getLevel();
    }

    @RequestMapping(value = "/setLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public String setLoglevel(@RequestParam("loglevel") String logLevel, @RequestParam(value="package") String packageName) throws Exception {
  
        logger.info("setLoglevel packageName is {},logLevel is {}",packageName,logLevel);
        try{
        Configurator.setLevel(packageName,Level.valueOf(logLevel));
        }catch (Exception e){
            logger.error("Exception setLoglevel packageName is {},logLevel is {}",packageName,logLevel,e);
            return "fail";
        }
        return "success";
    }
    @RequestMapping(value = "/setRootLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public String setRootLoglevel(@RequestParam("loglevel") String logLevel) throws Exception {
        logger.info("setRootLoglevel ,logLevel is {}",logLevel);
        try {
            //设置根记录器
            Configurator.setRootLevel(Level.valueOf(logLevel));
        }catch (Exception e){
            logger.error("Exception setRootLoglevel ,logLevel is {}",logLevel,e);
            return  "fail";
        }
        return "success";
    }
    @RequestMapping(value = "/testLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public String testLoglevel() throws Exception {
        logger.debug("current log level is debug..........debug...");
        logger.info("current log level is info.........info......");
        logger.warn("current log level is warn.......warn.......");
        logger.error("current log level is error.......error.......");

        return "success";
    }
}

-----------------LogbackController-------------------------

@Api(tags = "LogbackController",description = "logback控制类")
@RestController
@RequestMapping("/log/control")
public class LogbackController {
    private static Logger logger = LoggerFactory.getLogger(LogbackController.class);

    @RequestMapping(value = "/getLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public Level getLoglevel(@RequestParam(value="package") String packageName) throws Exception {//package 指定修改日志级别的包路径 ，如 org.mybatis
        logger.info("getLoglevel packageName is {}",packageName);
        LoggerContext loggerContext = (LoggerContext)LoggerFactory.getILoggerFactory();
        return loggerContext.getLogger(packageName).getLevel();
    }

    @RequestMapping(value = "/setLoglevel", method = {RequestMethod.GET, RequestMethod.POST})
    @ResponseBody
    public String setLoglevel(@RequestParam("loglevel") String logLevel, @RequestParam(value="package") String packageName) throws Exception {
        logger.info("setLoglevel packageName is {},logLevel is {}",packageName,logLevel);
        try{
        LoggerContext loggerContext =(LoggerContext)LoggerFactory.getILoggerFactory();
        loggerContext.getLogger(packageName).setLevel(Level.valueOf(logLevel));
        }catch (Exception e){
            logger.error("Exception packageName is {},logLevel is {}",packageName,logLevel,e);
            return "fail";
        }
        return "success";
    }

    @RequestMapping(value = "/setRootLoglevel", method = {RequestMethod.GET, RequestMethod.POST})
    @ResponseBody
    public String setRootLoglevel(@RequestParam("loglevel") String logLevel) throws Exception {
        logger.info("setRootLoglevel ,logLevel is {}",logLevel);
        try{
            LoggerContext loggerContext =(LoggerContext)LoggerFactory.getILoggerFactory();
            //设置全局日志级别
            ch.qos.logback.classic.Logger logger=loggerContext.getLogger("root");
            logger.setLevel(Level.toLevel(logLevel));
        }catch (Exception e){
            logger.error("Exception setRootLoglevel,logLevel is {}",logLevel,e);
            return "fail";
        }
        return "success";
    }

    @RequestMapping(value = "/testLoglevel", method = {RequestMethod.GET, RequestMethod.POST})
    @ResponseBody
    public String testLoglevel() throws Exception {
        logger.debug("current log level is debug..........debug...");
        logger.info("current log level is info.........info......");
        logger.warn("current log level is warn.......warn.......");
        logger.error("current log level is error.......error.......");

        return "success";
    }
}
-----------------Log4jController-------------------------

@Api(tags = "Log4jController",description = "Log4j控制类")
@Controller
@RequestMapping("/log/control")
public class Log4jController extends BaseController {
    private static final Logger logger = LoggerFactory.getLogger(Log4jController.class);

    @RequestMapping(value = "/getLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public void getLoglevel(@RequestParam(value="package") String packageName,@RequestParam(value="token") String token,HttpServletRequest request, HttpServletResponse response)  {
//package 指定修改日志级别的包路径 ，如 org.mybatis
        if(validateToken(token,request)==false){
            sendJson(response,NO_RIGHT_MSG);
            return;
        }
        logger.info("getLoglevel packageName is {}",packageName);
        org.apache.log4j.Logger log = LogManager.getLogger(packageName);
        sendJson(response,log.getLevel().toString());;
    }

    @RequestMapping(value = "/setOneLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public void setOneLoglevel(@RequestParam("loglevel") String logLevel, @RequestParam(value="package") String packageName,@RequestParam(value="token") String token,HttpServletRequest request, HttpServletResponse response) throws Exception {
        if(validateToken(token,request)==false){
            sendJson(response,NO_RIGHT_MSG);
            return;
        }
        //trace --> debug --> info --> warn --> error -->fatal
        logger.info("setOneLoglevel packageName is {},logLevel is {}",packageName,logLevel);
        try{
            Level level = Level.toLevel(logLevel.toUpperCase());
            org.apache.log4j.Logger log = LogManager.getLogger(packageName);
            log.setLevel(level);
        }catch (Exception e){
            logger.error("Exception setLoglevel packageName is "+packageName+",logLevel is "+logLevel,e);
            sendJson(response,"fail");
        }
        sendJson(response,"success");
    }
    @RequestMapping(value = "/setTwoLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public String setTwoLoglevel(@RequestParam("rootlevel") String rootLevel, @RequestParam("loglevel") String logLevel, @RequestParam(value="package") String packageName,@RequestParam(value="token") String token,HttpServletRequest request, HttpServletResponse response) throws Exception {
        if(validateToken(token,request)==false){
            sendJson(response,NO_RIGHT_MSG);
            return "false";
        }
        logger.info("setTwoLoglevel packageName is {},rootLevel is {},logLevel is {}",packageName,logLevel);

        setRootLoglevel(rootLevel,token,request,response);

        setOneLoglevel(logLevel,token,packageName,request,response);

        return "success";
    }
    @RequestMapping(value = "/setRootLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public void setRootLoglevel(@RequestParam("loglevel") String logLevel,@RequestParam(value="token") String token,HttpServletRequest request, HttpServletResponse response) throws Exception {
        if(validateToken(token,request)==false){
            sendJson(response,NO_RIGHT_MSG);
            return;
        }
        logger.info("setRootLoglevel ,logLevel is {}",logLevel);
        //all --> trace --> debug --> info --> warn --> error -->fatal --> off
        try {
            //设置根记录器
            org.apache.log4j.Logger log = LogManager.getRootLogger();
            log.setLevel(Level.toLevel(logLevel.toUpperCase()));
        }catch (Exception e){
            logger.error("Exception setRootLoglevel ,logLevel is {}",logLevel,e);
            sendJson(response,"fail");
        }
        sendJson(response,"success");
    }
    @RequestMapping(value = "/getRootlevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public void getRootlevel(@RequestParam(value="token") String token,HttpServletRequest request, HttpServletResponse response)  {//package 指定修改日志级别的包路径 ，如 org.mybatis
        if(validateToken(token,request)==false){
            sendJson(response,NO_RIGHT_MSG);
            return;
        }
        logger.info("getRootlevel....");

        org.apache.log4j.Logger log = LogManager.getRootLogger();
        sendJson(response,log.getLevel().toString());;
    }
    @RequestMapping(value = "/testLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public void testLoglevel(@RequestParam(value="token") String token,HttpServletRequest request, HttpServletResponse response) throws Exception {
        if(validateToken(token,request)==false){
            sendJson(response,NO_RIGHT_MSG);
            return;
        }
        logger.debug("current log level is debug..........debug...");
        logger.info("current log level is info.........info......");
        logger.warn("current log level is warn.......warn.......");
        logger.error("current log level is error.......error.......");

        sendJson(response,"success");

    }

    /**
     * todo 此API不太准，覆盖的级别不全，导致输出结果可能不准确
     * @param request
     * @param response
     * @throws Exception
     */
    @RequestMapping(value = "/getCurrentLoglevel", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
    public void getCurrentLoglevel(@RequestParam(value="token") String token,HttpServletRequest request, HttpServletResponse response) throws Exception {
        if(validateToken(token,request)==false){
            sendJson(response,NO_RIGHT_MSG);
            return;
        }
        String result ="wrong level recognized";
        if(logger.isDebugEnabled()){
            logger.debug("current log level is debug..........debug...");
            result= "current log level is debug";
        }else if (logger.isInfoEnabled()){
            logger.info("current log level is info.........info......");
            result=  "current log level is info";
        }else if(logger.isErrorEnabled()){
            logger.info("current log level is error.........error......");
            result=  "current log level is error";
        }else if(logger.isWarnEnabled()){
            logger.warn("current log level is warn.......warn.......");
            result=  "current log level is warn";
        }else {
            logger.error("current log level is not right.......wrong.......");
            result=  "current log level is right";
        }
        sendJson(response,result);

    }
    /**
     * 查看现在包的日志级别
     * @return
     */
    @RequestMapping(value =  "/loggers" , method = RequestMethod.GET)
    public void index(@RequestParam(value="token") String token,HttpServletRequest request, HttpServletResponse response) {
        if(validateToken(token,request)==false){
            sendJson(response,NO_RIGHT_MSG);
            return;
        }
        StringBuilder sb =  new  StringBuilder();
        try  {
            sb.append( "<html>" );
            Writer writer = response.getWriter();
            response.setCharacterEncoding( "UTF-8" );
            response.setContentType( "text/html; charset=utf-8" );
            Enumeration logs = LogManager.getCurrentLoggers();
            while  (logs.hasMoreElements()) {
                org.apache.log4j.Logger logger = (org.apache.log4j.Logger) logs.nextElement();
                sb.append( "<span style='display:block;'>" );
                sb.append(logger.getName()).append( ",\t" ).append(logger.getEffectiveLevel());
                sb.append( "</span>" );
            }
            sb.append( "</html>" );
            writer.write(sb.toString());
            writer.flush();
            if (writer !=  null ){
                writer.close();
            }
            System.out.println(sb.toString());
            sendJson(response,sb.toString());
        }  catch  (Exception e) {
            logger.error("Exception loggers ",e);
            sendJson(response,"fail");
        }    }    


@Autowired
private CacheUtil cacheUtil;

//令牌指定长度
private static  final  int token_length = 20;
//token使用限制次数
private static  final  int token_use_max_times = 10;
//缓存时间常量-1小时(计量秒)
public static final int EXPIRE_ONE_HOUR = 3600;
    private static final String LOGCONTROL_CACHE_KEY_PREFIX = "LOGCONTROL_CACHE_KEY_";
    protected final String NO_RIGHT_MSG="您没有API权限,请联系管理员!";

    private boolean validateToken(String token,HttpServletRequest request)  {        String userName = LoginUtils.getuserName(request)
;
logger.info("validateToken token is {} ,userName is {}",token,userName);
        if(checkuserNameAuth(userName)==false){            
logger.info("没有API权限 validateToken ,userName is {}",userName);
            return false;
        }        Object obj = 
cacheUtil.get(LOGCONTROL_CACHE_KEY_PREFIX+token);
        if(obj!=null){            Integer count = Integer.
valueOf(obj.toString());
            if(count!=null && count<=token_use_max_times){                
cacheUtil.incr(LOGCONTROL_CACHE_KEY_PREFIX+token);
                return true;
            }        }        


return false;

    }    
//是否是超管
private boolean checkuserNameAuth(String userName) {        String surperUsers = 

cacheUtils.getSpuers();
logger.error("surperUsers is "+surperUsers);
        return Arrays.asList(surperUsers.split(",")).contains(userName);
    }    
/**
     * @param request
* @param response
* @throws Exception
     */
//    @RequestMapuserNameg(value = "/getAccessToken", method = {RequestMethod.GET, RequestMethod.POST}, produces = "application/json;charset=UTF-8")
public void getAccessToken(HttpServletRequest request, HttpServletResponse response) throws Exception {        String userName = LoginUtils.getuserName(request)
;
logger.info("getAccessToken  userName is {}",userName);
        if(checkuserNameAuth(userName)==false){            
logger.info("没有API权限 validateToken ,userName is {}",userName);
            sendJson(response,NO_RIGHT_MSG);
            return;
        }        String token =
getRandomString(token_length);
logger.error("getAccessToken value " + token);
        try{            
cacheUtil.setEx(LOGCONTROL_CACHE_KEY_PREFIX+token,0,EXPIRE_ONE_HOUR);
        }catch (Exception e){            
logger.error("getAccessToken jimdb exception ",e);
        }        sendJson(response
,token);
    }    
//length用户要求产生字符串的长度
public static String getRandomString(int length){        String str=
"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
        Random random=new Random();
        StringBuffer sb=new StringBuffer();
        for(int i=0;i<length;i++){            
int number=random.nextInt(52);
            sb.append(str.charAt(number));
        }        
return sb.toString();
    }}

备注：
  1、logback和log4j2也有其它方式动态修改日志，但需要有方案或权限修改线上部署服务器的修改权限
      比如logback.xml中的configuration标签有<configuration scan="true" scanPeriod="60 seconds" debug="false">这种配置，
  其中的scan如果设置为true的话，项目在启动后就会默认每一分钟自动扫描配置文件，如果有改变则重新加载，而我们还可以设置自动扫描的时间间隔属性scanPeriod，可以设置成30秒或者5分钟。
  现在只要在logback.xml中添加一个属性，以后可以直接在服务器上修改logback.xml中root的level属性或者直接替换整个logback.xml文件，然后过会项目的日志输出级别就会改变了，不需要再重启项目。 
  2、本文主要介绍代码动态修改线上日志级别
  3、log4j2遇到的坑，如果把某个logger的日志级别修改成debug，日志文件一直不会打印，但控制台会正常打印。
   经排查是log4j2.xml中appender的过滤级别配置导致的，如下：
   修改前：
    <Filters>
       <ThresholdFilter level="info" onMatch="ACCEPT"  onMismatch="DENY"/>
    </Filters>

   修改后：
   <Filters>
      <ThresholdFilter level="info" onMatch="ACCEPT"  onMismatch="NEUTRAL"/>
   </Filters>

 简单对比说明：
  onMatch和onMismatch都有三个属性值：Accept、DENY和NEUTRAL
  onMatch="ACCEPT" 表示匹配该级别及以上
  onMatch="DENY"   表示不匹配该级别及以上
  onMatch="NEUTRAL" 表示该级别及以上的，由下一个filter处理，如果当前是最后一个，则表示匹配该级别及以上
  onMismatch="ACCEPT" 表示匹配该级别以下
  onMismatch="NEUTRAL" 表示该级别及以下的，由下一个filter处理，如果当前是最后一个，则不匹配该级别以下的
  onMismatch="DENY" 表示不匹配该级别以下的 

  4、参照Log4jController可以增加AccessToken鉴权和权限过期机制