Play fails to load custom log back appender

Question

I have created a custom logback appender. But play gives a ClassNotFound exception for the appender.

Following is my appender

package log

import ch.qos.logback.core.AppenderBase
import ch.qos.logback.core.UnsynchronizedAppenderBase
import ch.qos.logback.core.spi.ContextAwareBase
import log.model.LogMessage
import data.OrganizationDao
import log.dao.LogDao
import ch.qos.logback.core.status.Status

class MongoAppender extends ContextAwareBase {
  private def add(level:Int, msg: String, ex: Throwable) = {
    val message = ex match {
      case null => LogMessage(None, level, msg, null, null, new Array[String](0))
      case _ => LogMessage(None, level, msg, ex.getClass().getName(), ex.getMessage(), new Array[String](0))
    }

    LogDao.save(message)

  }
  override def addStatus(status:Status) = {
    add(status.getLevel(), status.getMessage(), status.getThrowable())
  }

}

The following is my logger.xml

<configuration>

    <conversionRule conversionWord="coloredLevel"
        converterClass="play.api.Logger$ColoredLevel" />

    <appender name="Mongo" class="log.MongoAppender">

    </appender>



    <logger name="play" level="INFO" />
    <logger name="application" level="INFO" />

    <root level="ERROR">
        <appender-ref ref="Mongo" />
    </root>

</configuration>

I am getting the following stacktrace

Caused by: java.lang.ClassNotFoundException: log.MongoAppender
        at      at java.net.URLClassLoader$1.run(Unknown Source)
        at      at java.net.URLClassLoader$1.run(Unknown Source)
        at      at java.security.AccessController.doPrivileged(Native Method)
        at      at java.net.URLClassLoader.findClass(Unknown Source)
        at      at java.lang.ClassLoader.loadClass(Unknown Source)
        at      at java.lang.ClassLoader.loadClass(Unknown Source)
        at      at ch.qos.logback.core.util.OptionHelper.instantiateByClassNameA
ndParameter(OptionHelper.java:60)

I have checked that the appender class does compile and also checked the compiled byte code. Why does not play pick it up?

Answer 1

It seems that play's dynamically compiled classes in dev mode are not available for logback. I'm struggling with the same issue. Putting my custom appender to a separate jar file works for me. I assume in prod with staged final jar files this should not be a problem.