GH-15684 - redirect ERROR also to stderr

h2oai · Feb 14, 2024 · 0e4d4cd · 0e4d4cd
1 parent 7b73f6a
commit 0e4d4cd
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Showing 2 changed files with 13 additions and 1 deletion.
diff --git a/h2o-logging/impl-log4j2/src/main/java/water/util/LoggerBackend.java b/h2o-logging/impl-log4j2/src/main/java/water/util/LoggerBackend.java
@@ -83,6 +83,11 @@ public void reconfigureLog4J() {
                 .addAttribute("target", "SYSTEM_OUT")
                 .add(layoutComponentBuilder));
 
+        builder.add(builder.newAppender("stderr", "Console")
+                .addAttribute("target", "SYSTEM_ERR")
+                .add(builder.newFilter("ThresholdFilter", Filter.Result.ACCEPT, Filter.Result.DENY).addAttribute("level", Level.ERROR))
+                .add(layoutComponentBuilder));
+
         builder.add(newRollingFileAppenderComponent(builder, "R1", "1MB", _getLogFilePath.apply("trace"), pattern, Level.TRACE));
         builder.add(newRollingFileAppenderComponent(builder, "R2", _maxLogFileSize, _getLogFilePath.apply("debug"), pattern, Level.DEBUG));
         builder.add(newRollingFileAppenderComponent(builder, "R3", _maxLogFileSize, _getLogFilePath.apply("info"), pattern, Level.INFO));
@@ -92,6 +97,7 @@ public void reconfigureLog4J() {
         builder.add(newRollingFileAppenderComponent(builder, "HTTPD", "1MB", _getLogFilePath.apply("httpd"), "%d{ISO8601} " + patternTail, Level.TRACE));
 
         AppenderRefComponentBuilder consoleAppenderRef = builder.newAppenderRef("Console");
+        AppenderRefComponentBuilder stderrAppenderRef = builder.newAppenderRef("stderr");
 
         // configure loggers:
         List<AppenderRefComponentBuilder> appenderReferences = new ArrayList();
@@ -102,11 +108,12 @@ public void reconfigureLog4J() {
         appenderReferences.add(builder.newAppenderRef("R5"));
         appenderReferences.add(builder.newAppenderRef("R6"));
         appenderReferences.add(consoleAppenderRef);
+        appenderReferences.add(stderrAppenderRef);
 
         builder.add(newLoggerComponent(builder, "hex", appenderReferences));
         builder.add(newLoggerComponent(builder, "water", appenderReferences));
         builder.add(newLoggerComponent(builder, "ai.h2o", appenderReferences));
-        builder.add(builder.newRootLogger(String.valueOf(L4J_LVLS[_level])).add(consoleAppenderRef));
+        builder.add(builder.newRootLogger(String.valueOf(L4J_LVLS[_level])).add(consoleAppenderRef).add(stderrAppenderRef));
 
         // Turn down the logging for some class hierarchies.
         builder.add(newLoggerComponent(builder, "org.apache.http", appenderReferences, "WARN"));

diff --git a/h2o-logging/impl-log4j2/src/main/resources/log4j2.xml b/h2o-logging/impl-log4j2/src/main/resources/log4j2.xml
@@ -4,10 +4,15 @@
         <Console name="Console" target="SYSTEM_OUT">
             <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
         </Console>
+        <Console name="stderr" target="SYSTEM_ERR"> <!-- 2 -->
+            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
+            <ThresholdFilter level="ERROR" onMatch="ACCEPT" onMismatch="DENY"/> <!-- 3 -->
+        </Console>
     </Appenders>
     <Loggers>
         <Root level="info">
             <AppenderRef ref="Console"/>
+            <AppenderRef ref="stderr"/>
         </Root>
     </Loggers>
 </Configuration>