app/monitoring/SentryLogging.scala

package monitoring

import ch.qos.logback.classic.filter.ThresholdFilter
import ch.qos.logback.classic.{Logger, LoggerContext}
import com.getsentry.raven.RavenFactory.ravenInstance
import com.getsentry.raven.dsn.Dsn
import com.getsentry.raven.logback.SentryAppender
import org.slf4j.Logger.ROOT_LOGGER_NAME
import org.slf4j.LoggerFactory
import play.api.Logging

class SentryLogging(
  config: play.api.Configuration
) extends Logging {

  val dsnOpt: Option[Dsn] = config.getOptional[String]("sentry.dsn").map(new Dsn(_))

  def init(): Unit = dsnOpt match {
    case None =>
      logger.warn("No Sentry logging configured (OK for dev)")
    case Some(dsn) =>
      logger.info(s"Initialising Sentry logging for ${dsn.getHost}")
      val tags = Map("gitCommitId" -> app.BuildInfo.gitCommitId)
      val tagsString = tags.map { case (key, value) => s"$key:$value" }.mkString(",")

      val filter = new ThresholdFilter { setLevel("ERROR") }
      filter.start() // OMG WHY IS THIS NECESSARY LOGBACK?

      val sentryAppender = new SentryAppender(ravenInstance(dsn)) {
        addFilter(filter)
        setTags(tagsString)
        setContext(LoggerFactory.getILoggerFactory.asInstanceOf[LoggerContext])
      }
      sentryAppender.start()
      LoggerFactory.getLogger(ROOT_LOGGER_NAME).asInstanceOf[Logger].addAppender(sentryAppender)
  }
}