我的团队使用Spring Boot Admin
来控制我们的spring application
,
在Spring Boot Admin
中,我们可以选择更改Runtime
中的logger
级别,
我们为每个task
(线程)都有一个单独的记录器,如果我们只想查看一个线程的控制台日志,我们将关闭所有其他线程记录器,
问题在于,每个记录器都会同时发送STDOUT
和特定文件的输出,而我们只想关闭 标准输出。
log4j2.xml配置示例:
<Loggers>
<Logger name="task1" level="info">
<AppenderRef ref="Console"/>
<AppenderRef ref="File"/>
</Logger>
<Logger name="task2" level="info">
<AppenderRef ref="Console"/>
<AppenderRef ref="File"/>
</Logger>
</Loggers>
我们尝试了很多解决方案:
答案 0 :(得分:2)
默认情况下,Log4j2不允许管理System.out和System.err流。
要阐明控制台记录器如何工作:
只需Console
附加程序即可将其输出打印到System.out或System.err。根据文档,如果默认情况下未指定目标,它将打印到System.out:
https://logging.apache.org/log4j/2.x/manual/appenders.html
目标||字符串|| “ SYSTEM_OUT”或“ SYSTEM_ERR”。默认值为“ SYSTEM_OUT”。
以下是示例:
log4j2.xml
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<Properties>
<Property name="log-pattern">%d{ISO8601} %-5p %m\n</Property>
</Properties>
<appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout>
<pattern>${log-pattern}</pattern>
</PatternLayout>
</Console>
</appenders>
<Loggers>
<logger name="testLogger" level="info" additivity="false">
<AppenderRef ref="Console"/>
</logger>
</Loggers>
</configuration>
LogApp.java
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
public class LogApp {
public static void main(String[] args) {
Logger log = LogManager.getLogger("testLogger");
log.info("Logger output test!");
System.out.println("System out test!");
}
}
输出:
2019-01-08T19:08:57,587 INFO Logger output test!
System out test!
管理系统流的解决方法
参加Dmitry Pavlenko的流重定向课程
https://sysgears.com/articles/how-to-redirect-stdout-and-stderr-writing-to-a-log4j-appender/
import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.Logger;
import java.io.IOException;
import java.io.OutputStream;
/**
* A change was made on the existing code:
* - At (LoggingOutputStream#flush) method 'count' could contain
* single space character, this types of logs has been skipped
*/
public class LoggingOutputStream extends OutputStream {
private static final int DEFAULT_BUFFER_LENGTH = 2048;
private boolean hasBeenClosed = false;
private byte[] buf;
private int count;
private int curBufLength;
private Logger log;
private Level level;
public LoggingOutputStream(final Logger log,
final Level level)
throws IllegalArgumentException {
if (log == null || level == null) {
throw new IllegalArgumentException(
"Logger or log level must be not null");
}
this.log = log;
this.level = level;
curBufLength = DEFAULT_BUFFER_LENGTH;
buf = new byte[curBufLength];
count = 0;
}
public void write(final int b) throws IOException {
if (hasBeenClosed) {
throw new IOException("The stream has been closed.");
}
// don't log nulls
if (b == 0) {
return;
}
// would this be writing past the buffer?
if (count == curBufLength) {
// grow the buffer
final int newBufLength = curBufLength +
DEFAULT_BUFFER_LENGTH;
final byte[] newBuf = new byte[newBufLength];
System.arraycopy(buf, 0, newBuf, 0, curBufLength);
buf = newBuf;
curBufLength = newBufLength;
}
buf[count] = (byte) b;
count++;
}
public void flush() {
if (count <= 1) {
count = 0;
return;
}
final byte[] bytes = new byte[count];
System.arraycopy(buf, 0, bytes, 0, count);
String str = new String(bytes);
log.log(level, str);
count = 0;
}
public void close() {
flush();
hasBeenClosed = true;
}
}
然后为系统输出流创建一个自定义记录器,而不是对其进行注册。
这是记录器用法的完整代码:
log4j2.xml
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<Properties>
<Property name="log-pattern">%d{ISO8601} %-5p %m\n</Property>
</Properties>
<appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout>
<pattern>${log-pattern}</pattern>
</PatternLayout>
</Console>
</appenders>
<Loggers>
<logger name="testLogger" level="info" additivity="false">
<AppenderRef ref="Console"/>
</logger>
<logger name="systemOut" level="info" additivity="true"/>
</Loggers>
</configuration>
SystemLogging.java
import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.LogManager;
import java.io.PrintStream;
public class SystemLogging {
public void enableOutStreamLogging() {
System.setOut(createPrintStream("systemOut", Level.INFO));
}
private PrintStream createPrintStream(String name, Level level) {
return new PrintStream(new LoggingOutputStream(LogManager.getLogger(name), level), true);
}
}
LogApp.java
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
public class LogApp {
public static void main(String[] args) {
new SystemLogging().enableOutStreamLogging();
Logger log = LogManager.getLogger("testLogger");
log.info("Logger output test!");
System.out.println("System out test!");
}
}
最终输出
2019-01-08T19:30:43,456 INFO Logger output test!
19:30:43.457 [main] INFO systemOut - System out test!
现在,根据需要使用新的记录器配置自定义系统。
加上;如果您不想覆盖System.out
而只想保存它:TeeOutputStream库中有commons-io。您只需将原始System.out
和System.out
的组合替换为原始LoggingOutputStream
和System.out
即可同时写入两个流。这不会更改原始输出,但允许您使用日志记录附加程序保存variable "AutoStopSchedule" {
default = "5"
}
locals{
schedule_expression= "cron(${var.AutoStopSchedule} * * * ? *)"
}
output "schedule_expression" {
value = "${local.schedule_expression}"
}
。