通过Arthas来动态打印日志

需求
线上一个Spring boot应用 通过MyBatis来操作数据库 定位一个线上问题 想动态打印sql日志

解决
通过Arthas工具来实现上述的需求

$ ognl '@org.slf4j.LoggerFactory@getLogger("com.foo.cpts.mapper")'@Logger[    serialVersionUID=@Long[5454405123156820674],    FQCN=@String[ch.qos.logback.classic.Logger],    name=@String[com.foo.cpts.mapper],    level=null,    effectiveLevelInt=@Integer[20000],    parent=@Logger[Logger[com.foo.cpts]],    childrenList=@CopyOnWriteArrayList[isEmpty=false;size=2],    aai=null,    additive=@Boolean[true],    loggerContext=@LoggerContext[ch.qos.logback.classic.LoggerContext[default]],]

刚开始Mapper包对应的日志级别是null 将其改成DEBUG

$ ognl '@org.slf4j.LoggerFactory@getLogger("com.foo.cpts.mapper").setLevel(@ch.qos.logback.classic.Level@DEBUG)'null$ ognl '@org.slf4j.LoggerFactory@getLogger("com.foo.cpts.mapper")'@Logger[    serialVersionUID=@Long[5454405123156820674],    FQCN=@String[ch.qos.logback.classic.Logger],    name=@String[com.foo.cpts.mapper],    level=@Level[DEBUG],    effectiveLevelInt=@Integer[10000],    parent=@Logger[Logger[com.foo.cpts]],    childrenList=@CopyOnWriteArrayList[isEmpty=false;size=2],    aai=null,    additive=@Boolean[true],    loggerContext=@LoggerContext[ch.qos.logback.classic.LoggerContext[default]],]

此时当调用Mapper方法时 能打印出sql日志了 同样关闭sql日志 改成info即可

$ ognl '@org.slf4j.LoggerFactory@getLogger("com.foo.cpts.mapper").setLevel(@ch.qos.logback.classic.Level@INFO)'null

补充
因为打印sql日志对应的配置是

logging.level.com.foo.cpts.mapper=DEBUG

刚开始想着通过下面的方式来实现

ognl '@java.lang.System@setProperty("logging.level.com.foo.cpts.mapper","DEBUG")'

但是该方式并未起作用