package com.drivergrp.core
import java.io.File
import java.nio.file.{Path, Paths}
import java.util.UUID._
import com.amazonaws.services.s3.AmazonS3
import com.amazonaws.services.s3.model.{Bucket, GetObjectRequest, ListObjectsV2Request}
import com.drivergrp.core.time.Time
import scala.concurrent.{ExecutionContext, Future}
import scalaz.{ListT, OptionT}
object file {
final case class FileLink(
id: Id[File],
name: Name[File],
location: Path,
additionDate: Time
)
trait FileService {
def getFileLink(id: Id[File]): FileLink
def getFile(fileLink: FileLink): File
}
trait FileStorage {
def upload(localSource: File, destination: Path): Future[Unit]
def download(filePath: Path): OptionT[Future, File]
def delete(filePath: Path): Future[Unit]
def list(path: Path): ListT[Future, Name[File]]
/** List of characters to avoid in S3 (I would say file names in general)
*
* @see http://stackoverflow.com/questions/7116450/what-are-valid-s3-key-names-that-can-be-accessed-via-the-s3-rest-api
*/
private val illegalChars = "\\^`><{}][#%~|&@:,$=+?; "
protected def checkSafeFileName[T](filePath: Path)(f: => T): T = {
filePath.toString.find(c => illegalChars.contains(c)) match {
case Some(illegalCharacter) =>
throw new IllegalArgumentException(s"File name cannot contain character `$illegalCharacter`")
case None => f
}
}
}
class S3Storage(s3: AmazonS3, bucket: Name[Bucket], executionContext: ExecutionContext) extends FileStorage {
implicit private val execution = executionContext
def upload(localSource: File, destination: Path): Future[Unit] = Future {
checkSafeFileName(destination) {
val _ = s3.putObject(bucket, destination.toString, localSource).getETag
}
}
def download(filePath: Path): OptionT[Future, File] = OptionT.optionT(Future {
val tempDir = System.getProperty("java.io.tmpdir")
val randomFolderName = randomUUID().toString
val tempDestinationFile = new File(Paths.get(tempDir, randomFolderName, filePath.toString).toString)
if (!tempDestinationFile.getParentFile.mkdirs()) {
throw new Exception(s"Failed to create temp directory to download file `$file`")
} else {
Option(s3.getObject(new GetObjectRequest(bucket, filePath.toString), tempDestinationFile)).map { _ =>
tempDestinationFile
}
}
})
def delete(filePath: Path): Future[Unit] = Future {
s3.deleteObject(bucket, filePath.toString)
}
def list(path: Path): ListT[Future, Name[File]] =
ListT.listT(Future {
import scala.collection.JavaConverters._
val req = new ListObjectsV2Request().withBucketName(bucket).withPrefix(path.toString).withMaxKeys(2)
Iterator.continually(s3.listObjectsV2(req)).takeWhile { result =>
req.setContinuationToken(result.getNextContinuationToken)
result.isTruncated
} flatMap { result =>
result.getObjectSummaries.asScala
.map(_.getKey)
.toList
.filterNot(_.replace(path.toString + "/", "").contains("/")) // filter out sub-folders or files in sub-folders
.map(item => Name[File](new File(item).getName))
} toList
})
}
class FileSystemStorage(executionContext: ExecutionContext) extends FileStorage {
implicit private val execution = executionContext
def upload(localSource: File, destination: Path): Future[Unit] = Future {
checkSafeFileName(destination) {
val destinationFile = destination.toFile
if (destinationFile.getParentFile.exists() || destinationFile.getParentFile.mkdirs()) {
if (localSource.renameTo(destinationFile)) ()
else {
throw new Exception(
s"Failed to move file from `${localSource.getCanonicalPath}` to `${destinationFile.getCanonicalPath}`")
}
} else {
throw new Exception(s"Failed to create parent directories for file `${destinationFile.getCanonicalPath}`")
}
}
}
def download(filePath: Path): OptionT[Future, File] = OptionT.optionT(Future {
Option(new File(filePath.toString)).filter(file => file.exists() && file.isFile)
})
def delete(filePath: Path): Future[Unit] = Future {
val file = new File(filePath.toString)
if (file.delete()) ()
else {
throw new Exception(s"Failed to delete file $file" + (if (!file.exists()) ", file does not exist." else "."))
}
}
def list(path: Path): ListT[Future, Name[File]] =
ListT.listT(Future {
val file = new File(path.toString)
if (file.isDirectory) file.listFiles().filter(_.isFile).map(f => Name[File](f.getName)).toList
else List.empty[Name[File]]
})
}
}