Dropwizard Custom Appender

config.yml

server:
  type: default
  requestLog:
    appenders:
      - type: console-json
        name: request-log-console-json
        includeContextName: false
logging:
  level: INFO
  appenders:
    - type: console-json

ConsoleJsonAppenderFactory.java

package io.github.ajmath;

import io.dropwizard.logging.AbstractAppenderFactory;
import ch.qos.logback.classic.LoggerContext;
import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.contrib.jackson.JacksonJsonFormatter;
import ch.qos.logback.contrib.json.classic.JsonLayout;
import ch.qos.logback.core.Appender;
import ch.qos.logback.core.ConsoleAppender;
import ch.qos.logback.core.Layout;
import ch.qos.logback.core.encoder.LayoutWrappingEncoder;

import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonTypeName;

@JsonTypeName("console-json")
public class ConsoleJsonAppenderFactory extends AbstractAppenderFactory {
    
    private String appenderName = "console-json-appender";
    private boolean includeContextName = true;

    @JsonProperty
    public String getName() {
        return this.appenderName;
    }
    
    @JsonProperty
    public void setName(String name) {
        this.appenderName = name;
    }
    
    @JsonProperty
    public boolean getIncludeContextName() {
        return this.includeContextName;
    }
    
    @JsonProperty
    public void setIncludeContextName(boolean includeContextName) {
        this.includeContextName = includeContextName;
    }

    @Override
    public Appender<ILoggingEvent> build(LoggerContext context, String applicationName, Layout<ILoggingEvent> providedLayout) {
        JsonLayout layout = new JsonLayout();
        layout.setJsonFormatter(new JacksonJsonFormatter());
        layout.setAppendLineSeparator(true);
        layout.setTimestampFormatTimezoneId("UTC");
        layout.setIncludeContextName(includeContextName);
        
        LayoutWrappingEncoder<ILoggingEvent> layoutEncoder = new LayoutWrappingEncoder<>();
        layoutEncoder.setLayout(layout);
        
        ConsoleAppender<ILoggingEvent> appender = new ConsoleAppender<>();
        appender.setName(appenderName);
        appender.setContext(context);
        appender.setEncoder(layoutEncoder);
        addThresholdFilter(appender, threshold);
        appender.start();

        return wrapAsync(appender);
    }

}

io.dropwizard.logging.AppenderFactory

# Placed in src/main/resources/META-INF/services/io.dropwizard.logging.AppenderFactory without this line
io.dropwizard.logging.ConsoleAppenderFactory
io.dropwizard.logging.FileAppenderFactory
io.dropwizard.logging.SyslogAppenderFactory
io.github.ajmath.ConsoleJsonAppenderFactory