devlog-kotlin/dev.hermannm.devlog/LoggingContextJsonFieldWriter

LoggingContextJsonFieldWriter

class LoggingContextJsonFieldWriter : MdcEntryWriter(source)

Writes logging context fields as JSON when using logstash-logback-encoder. We need this in order to include object fields as raw JSON instead of escaped strings on the log output.

To use it, configure logback.xml under src/main/resources as follows:

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
    <encoder class="net.logstash.logback.encoder.LogstashEncoder">
      <!-- Writes object values from logging context as actual JSON (not escaped) -->
      <mdcEntryWriter class="dev.hermannm.devlog.LoggingContextJsonFieldWriter"/>
    </encoder>
  </appender>

  <root level="INFO">
    <appender-ref ref="STDOUT"/>
  </root>
</configuration>

This requires that you have added ch.qos.logback:logback-classic and net.logstash.logback:logstash-logback-encoder as dependencies.

Constructors

LoggingContextJsonFieldWriter

constructor()

Functions

writeMdcEntry

open override fun writeMdcEntry(generator: JsonGenerator, fieldName: String, mdcKey: String, value: String): Boolean