co.elastic.logging.log4j2.MdcSerializer Maven / Gradle / Ivy
/*-
* #%L
* Java ECS logging
* %%
* Copyright (C) 2019 - 2020 Elastic and contributors
* %%
* Licensed to Elasticsearch B.V. under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
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* the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
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*/
package co.elastic.logging.log4j2;
import co.elastic.logging.EcsJsonSerializer;
import co.elastic.logging.JsonUtils;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.util.TriConsumer;
interface MdcSerializer {
void serializeMdc(LogEvent event, StringBuilder builder);
class Resolver {
public static MdcSerializer resolve() {
try {
LogEvent.class.getMethod("getContextData");
return (MdcSerializer) Class.forName("co.elastic.logging.log4j2.MdcSerializer$UsingContextData").getEnumConstants()[0];
} catch (Exception ignore) {
} catch (LinkageError ignore) {
}
return UsingContextMap.INSTANCE;
}
}
/**
* Garbage free MDC serialization for log4j2 2.7+
* Never reference directly in prod code so avoid linkage errors when TriConsumer or getContextData are not available
*/
enum UsingContextData implements MdcSerializer {
INSTANCE;
private static final TriConsumer WRITE_MDC = new TriConsumer() {
@Override
public void accept(final String key, final Object value, final StringBuilder stringBuilder) {
stringBuilder.append('\"');
JsonUtils.quoteAsString(key, stringBuilder);
stringBuilder.append("\":\"");
JsonUtils.quoteAsString(EcsJsonSerializer.toNullSafeString(String.valueOf(value)), stringBuilder);
stringBuilder.append("\",");
}
};
@Override
public void serializeMdc(LogEvent event, StringBuilder builder) {
event.getContextData().forEach(WRITE_MDC, builder);
}
}
/**
* Fallback for log4j2 <= 2.6
*/
enum UsingContextMap implements MdcSerializer {
INSTANCE;
@Override
public void serializeMdc(LogEvent event, StringBuilder builder) {
EcsJsonSerializer.serializeMDC(builder, event.getContextMap());
}
}
}