Throttling logger

Author: labkey-adam

api/src/org/labkey/api/util/logging/LogHelper.java

@@ -2,6 +2,7 @@
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.spi.ExtendedLogger;
 
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
@@ -44,4 +45,9 @@ public static String getLabKeyLogDir()
     {
         return System.getProperty(LOG_HOME_PROPERTY_NAME);
     }
+
+    public static Logger getThrottlingLogger(Class<?> c, String note)
+    {
+        return new ThrottlingLogger((ExtendedLogger)getLogger(c, note));
+    }
 }

api/src/org/labkey/api/util/logging/ThrottlingLogger.java

@@ -0,0 +1,93 @@
+package org.labkey.api.util.logging;
+
+import org.apache.logging.log4j.Level;
+import org.apache.logging.log4j.Marker;
+import org.apache.logging.log4j.message.Message;
+import org.apache.logging.log4j.message.MessageFactory;
+import org.apache.logging.log4j.spi.ExtendedLogger;
+import org.apache.logging.log4j.spi.ExtendedLoggerWrapper;
+import org.labkey.api.cache.Cache;
+import org.labkey.api.cache.CacheManager;
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+public class ThrottlingLogger extends ExtendedLoggerWrapper
+{
+    private static final Cache<String, AtomicInteger> THROTTLING_CACHE = CacheManager.getBlockingCache(500, CacheManager.HOUR, "Throttle for Loggers", (_, _) -> new AtomicInteger(0));
+    private static final Message DUMMY_MESSAGE = new Message()
+    {
+        @Override
+        public String getFormattedMessage()
+        {
+            return null;
+        }
+
+        @Override
+        public Object[] getParameters()
+        {
+            return null;
+        }
+
+        @Override
+        public Throwable getThrowable()
+        {
+            return null;
+        }
+    };
+
+    public ThrottlingLogger(ExtendedLogger logger)
+    {
+        super(logger, logger.getName(), new ThrottlingMessageFactory(logger.getMessageFactory(), 20));
+    }
+
+    @Override
+    public void logMessage(final String fqcn, final Level level, final Marker marker, final Message message, final Throwable t)
+    {
+        if (message != DUMMY_MESSAGE)
+            super.logMessage(fqcn, level, marker, message, t);
+    }
+
+    private static class ThrottlingMessageFactory implements MessageFactory
+    {
+        private final MessageFactory _factory;
+        private final int _maxBurst;
+
+        private ThrottlingMessageFactory(MessageFactory factory, int maxBurst)
+        {
+            _factory = factory;
+            _maxBurst = maxBurst;
+        }
+
+        @Override
+        public Message newMessage(Object message)
+        {
+            String key = message == null ? "null" : message.toString();
+            return shouldLog(key) ? _factory.newMessage(message) : DUMMY_MESSAGE;
+        }
+
+        @Override
+        public Message newMessage(String message)
+        {
+            return shouldLog(message) ? _factory.newMessage(message) : DUMMY_MESSAGE;
+        }
+
+        @Override
+        public Message newMessage(String message, Object... params)
+        {
+            return shouldLog(message) ? _factory.newMessage(message, params) : DUMMY_MESSAGE;
+        }
+
+        private boolean shouldLog(String message)
+        {
+            AtomicInteger count = THROTTLING_CACHE.get(message);
+
+            if (count.intValue() < _maxBurst)
+            {
+                count.incrementAndGet();
+                return true;
+            }
+
+            return false;
+        }
+    }
+}

search/src/org/labkey/search/model/LuceneSearchServiceImpl.java

@@ -161,7 +161,7 @@
 
 public class LuceneSearchServiceImpl extends AbstractSearchService implements SearchMXBean
 {
-    private static final Logger _log = LogHelper.getLogger(LuceneSearchServiceImpl.class, "Full-text searching indexing operations");
+    private static final Logger _log = LogHelper.getThrottlingLogger(LuceneSearchServiceImpl.class, "Full-text searching indexing operations");
 
     // Changes to _index are rare (only when admin changes the index path), but we want any changes to be visible to
     // other threads immediately. Initialize to Noop class to prevent rare NPE (e.g., system maintenance runs before index
@@ -1334,7 +1334,7 @@ private void logAsWarning(WebdavResource r, String message)
 
     private void logAsWarning(WebdavResource r, String message, @Nullable String rootMessage)
     {
-        _log.warn("Can't index file \"" + getNameToLog(r) + "\" due to: " + message + (null != rootMessage ? " [" + rootMessage + "]" : ""));
+        _log.warn("Can't index file \"{}\" due to: {}{}", getNameToLog(r), message, null != rootMessage ? " [" + rootMessage + "]" : "");
     }
 
     private static class PreProcessingException extends Exception