org.elasticsearch.common.logging.RateLimitingFilter Maven / Gradle / Ivy
Show all versions of elasticsearch Show documentation
/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0 and the Server Side Public License, v 1; you may not use this file except
* in compliance with, at your election, the Elastic License 2.0 or the Server
* Side Public License, v 1.
*/
package org.elasticsearch.common.logging;
import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.Marker;
import org.apache.logging.log4j.core.Filter;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.Logger;
import org.apache.logging.log4j.core.config.Node;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
import org.apache.logging.log4j.core.filter.AbstractFilter;
import org.apache.logging.log4j.message.Message;
import org.elasticsearch.common.Strings;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import static org.elasticsearch.common.logging.DeprecatedMessage.ELASTIC_ORIGIN_FIELD_NAME;
import static org.elasticsearch.common.logging.DeprecatedMessage.KEY_FIELD_NAME;
import static org.elasticsearch.common.logging.DeprecatedMessage.X_OPAQUE_ID_FIELD_NAME;
/**
* A filter used for throttling deprecation logs.
* A throttling is based on a combined key which consists of `key` from the logged ESMessage and `x-opaque-id`
* passed by a user on a HTTP header.
* This filter works by using a lruKeyCache - a set of keys which prevents a second message with the same key to be logged.
* The lruKeyCache has a size limited to 128, which when breached will remove the oldest entries.
*
* It is possible to disable use of `x-opaque-id` as a key with {@link RateLimitingFilter#setUseXOpaqueId(boolean) }
*
* @see Log4j2 Filters
*/
@Plugin(name = "RateLimitingFilter", category = Node.CATEGORY, elementType = Filter.ELEMENT_TYPE)
public class RateLimitingFilter extends AbstractFilter {
// a flag to disable/enable use of xOpaqueId controlled by changing cluster setting
private volatile boolean useXOpaqueId = true;
private final Set lruKeyCache = Collections.newSetFromMap(Collections.synchronizedMap(new LinkedHashMap<>() {
@Override
protected boolean removeEldestEntry(final Map.Entry eldest) {
return size() > 128;
}
}));
public RateLimitingFilter() {
this(Result.ACCEPT, Result.DENY);
}
public RateLimitingFilter(Result onMatch, Result onMismatch) {
super(onMatch, onMismatch);
}
/**
* Clears the cache of previously-seen keys.
*/
public void reset() {
this.lruKeyCache.clear();
}
public Result filter(Message message) {
if (message instanceof final ESLogMessage esLogMessage) {
final String key = getKey(esLogMessage);
return lruKeyCache.add(key) ? Result.ACCEPT : Result.DENY;
} else {
return Result.NEUTRAL;
}
}
private String getKey(ESLogMessage esLogMessage) {
final String key = esLogMessage.get(KEY_FIELD_NAME);
final String productOrigin = esLogMessage.get(ELASTIC_ORIGIN_FIELD_NAME);
if (Strings.isNullOrEmpty(productOrigin) == false) {
return productOrigin + key;
}
if (useXOpaqueId) {
String xOpaqueId = esLogMessage.get(X_OPAQUE_ID_FIELD_NAME);
return xOpaqueId + key;
}
return key;
}
@Override
public Result filter(LogEvent event) {
return filter(event.getMessage());
}
@Override
public Result filter(Logger logger, Level level, Marker marker, Message msg, Throwable t) {
return filter(msg);
}
@PluginFactory
public static RateLimitingFilter createFilter(
@PluginAttribute("onMatch") final Result match,
@PluginAttribute("onMismatch") final Result mismatch
) {
return new RateLimitingFilter(match, mismatch);
}
public void setUseXOpaqueId(boolean useXOpaqueId) {
this.useXOpaqueId = useXOpaqueId;
}
}