ByteContentResult in Play Framework

Application.scala

package controllers

import play.api.mvc._
import utilities._

object Application extends Controller with ResultUtility {
  object DataStore {
    val filename = "hoge.gif"
    val contentType = "image/gif"
    val blobdata = "data".getBytes
  }

  def index = Action { request =>
    Ok.withByteContent(DataStore.contentType, Some(DataStore.filename), DataStore.blobdata)
  }
}

ByteContentResult.scala

package utilities

import play.api.mvc.SimpleResult
import play.api.libs.iteratee.Enumerator
import play.api.http.HeaderNames

trait ResultUtility {
  implicit class ByteContentResult(self: SimpleResult) {
    def withByteContent(contentType: String, filename: Option[String], content: Array[Byte]): SimpleResult = {
      val newHeader = self.header.copy(
        headers = self.header.headers
          ++ Map(HeaderNames.CONTENT_LENGTH -> content.length.toString, HeaderNames.CONTENT_TYPE -> contentType)
          ++ filename.map { fn =>
            Map(HeaderNames.CONTENT_DISPOSITION -> ("""attachment; filename="%s"""".format(fn)))
          }.getOrElse(Map.empty))
      SimpleResult(newHeader, Enumerator(content))
    }
  }
}