How to configure custom PatternLayout of a LoggingEventCompositeJsonEncoder?

i have created a custom PatternLayout i'm using in Access and File appenders of logback, and I would like to use it as well for a LoggingEventCompositeJsonEncoder.

Is it possible to configure the encoder with my layout, and how can i achieve this ?

Exemple of the file appender configuration :

<appender name="FILE"> <encoder> <layout> <pattern>${LOG_PATTERN}</pattern> </layout> </encoder> <file>${LOG_FILE}</file> <rollingPolicy> <!-- rotate every day --> <fileNamePattern>${logback.rollingPolicy.file.fileNamePattern}</fileNamePattern> <!-- Days of history --> <maxHistory>${logback.maxHistory.retention:-7}</maxHistory> </rollingPolicy> </appender> 

My logstash encoder :

<encoder> <providers> <timestamp>%d{ISO8601}</timestamp> <message/> <loggerName/> <context/> <mdc/> <pattern> <pattern> { "appVersion": "${build.version}", "appName": "${build.artifact}", "resourceType": "${logback.application.resource.type}", "resourceID": "${logback.application.resource.id}", "level": "%level", "hostname": "${logback.server.host}", "indexType": "${logback.logstash.index.type}" } </pattern> </layout> </pattern> <stackTrace/> </providers> </encoder> 

Where can i define the same PatternLayout here ? I've read here that

Every value in the template is treated as a pattern for logback's standard PatternLayout so it can be a combination of literal strings (for some constants) and various conversion specifiers (like %d for date).

So how i can configure my own ? Thanks for your help.

1 Answer

Well to solve this, i had to use a custom valueMasker to do the filtering, and apply the same filtering method than my layout to filter the field value.

Added to logback.xml :

<jsonGeneratorDecorator> <valueMasker/></jsonGeneratorDecorator> 

Java class is something like :

package com.me.util.logging; import com.fasterxml.jackson.core.JsonStreamContext; import net.logstash.logback.mask.ValueMasker; public class CustomValueMasker implements ValueMasker { @Override public Object mask(JsonStreamContext jsonStreamContext, Object o) { if (o instanceof CharSequence) { return doTransform((String) o); } return o; } /** * Do the message filtering * * @param msg the message of the event log * * @return the filtered message */ private String doTransform(String msg) { // Do whatever filtering needed here return msg; } }