def streamTargetContent()

in app/controllers/VaultController.scala [177:230]
41 lines of code
8 McCabe index (conditional complexity)

  def streamTargetContent(vaultId:String, oid:String, request:Request[AnyContent], uid:String) = {
    /*
    break down the ranges header into structured data
     */
    val rangesOrFailure = request.headers.get("Range") match {
      case Some(hdr)=>RangeHeader.fromStringHeader(hdr)
      case None=>Success(Seq())
    }

    withVaultForIdSync(vaultId) { implicit vault =>
      val omEntry = ObjectMatrixEntry(oid).getMetadataSync
      /*
    get hold of a streaming source, if possible
     */
      val maybeResult = rangesOrFailure.flatMap(ranges => {
        val userInfo = userInfoCache.infoForVaultId(vaultId)

        val responseSize = if (ranges.nonEmpty) {
          Some(ranges.foldLeft(0L)((acc, range) => acc + (range.end.getOrElse(omEntry.fileAttribues.get.size) - range.start.getOrElse(0L))))
        } else {
          omEntry.fileAttribues.map(_.size)
        }

        logger.debug(s"Ranges is ${ranges}")
        //log that we are starting a streamout
        val auditFile = AuditFile(omEntry.oid, "")
        auditActor ! actors.Audit.LogEvent(AuditEvent.STREAMOUT, uid, Some(auditFile), ranges)

        getStreamingSource(ranges, userInfo.get, omEntry, auditFile, uid) match {
          case Success(partialGraph) =>
            Success((Source.fromGraph(partialGraph), responseSize, headersForEntry(omEntry, ranges, responseSize), getMaybeMimetype(omEntry), ranges.nonEmpty))
          case Failure(err) => //if we did not get a source, log that
            auditActor ! actors.Audit.LogEvent(AuditEvent.OMERROR, uid, Some(auditFile), ranges, notes = Some(err.getMessage))
            logger.error(s"Could not set up streaming source: ", err)
            Failure(new RuntimeException("Could not set up streaming source, see logs for more details"))
        }
      })

      maybeResult match {
        case Success((byteSource, maybeResponseSize, headers, maybeMimetype, isPartialTransfer)) =>
          logger.debug(s"maybeResponseSize is $maybeResponseSize")

          Result(
            ResponseHeader(if (isPartialTransfer) 206 else 200, headers),
            HttpEntity.Streamed(byteSource.log("outputstream").addAttributes(
              Attributes.logLevels(
                onElement = Attributes.LogLevels.Info,
                onFailure = Attributes.LogLevels.Error,
                onFinish = Attributes.LogLevels.Info)), None, maybeMimetype)
          ) //we can't give a proper content length, because if we are sending multipart chunks that adds overhead to the request size.
        case Failure(err) => InternalServerError(GenericErrorResponse("error", err.getMessage).asJson)
      }
    }
  }