Script scala para baixar imagens do Amazon S3, criar um thumb e subí-lo de volta para lá. Video explicando o Script: https://www.youtube.com/watch?v=BR4OUTAF8T8. | ----- | Scala script that downloads images from Amazon S3, creates a thumb and sends it back. The video mentioned above explains the code, but it is only in portuguese. I might add ca…

s3-img-thumber

import com.amazonaws.auth.PropertiesCredentials
import com.amazonaws.services.s3.AmazonS3Client
import com.amazonaws.services.s3.model._
import java.io.File
import scala.collection.JavaConverters._

object migrator extends App {
  val imagens = new File("/tmp/imagens")
  if (!imagens.exists) imagens.mkdir
  
  val s3 = new AmazonS3Client(new PropertiesCredentials(new File("aws.credentials")))
  val bucketName = "jcranky-dev"
  val sufixos = List("-small.png", "-medium.png", "-large.png", "-verylarge.png")
  
  var objListing = s3.listObjects(bucketName)
  
  processListing(objListing)
  while (objListing.isTruncated) {
    objListing = s3.listNextBatchOfObjects(objListing)
    processListing(objListing)
  }
  
  def processListing(listing: ObjectListing) = {
    val sumarios = listing.getObjectSummaries.asScala.toList
  
    val filtrada = sumarios.filterNot(s => sufixos.exists(s.getKey.endsWith(_)))
    filtrada.foreach(s => process(s))
  
    def process(s: S3ObjectSummary) = {
      val imgFile = new File(imagens, s.getKey)
      s3.getObject(new GetObjectRequest(bucketName, s.getKey), imgFile)
    
      val noExtKey = s.getKey.take(s.getKey.length-4)
      new ImageThumber(imgFile, noExtKey).generateThumb(VeryLargeThumb)
    
      val thumbFile = new File(imagens, s"${noExtKey}-verylarge.png")
    
      val putRequest = new PutObjectRequest(bucketName, thumbFile.getName, thumbFile)
      putRequest.setCannedAcl(CannedAccessControlList.PublicRead)
    
      println("sending to s3: " + thumbFile.getName)
      s3.putObject(putRequest)
    }
  }
}


// ctrl + c lojinha

import java.awt.AlphaComposite
import java.awt.image.BufferedImage
import java.io.File
import javax.imageio.ImageIO

class ImageThumber(image: File, imageKey: String) {
  def generateThumbs(): List[(File, String)] = ImageThumber.sizes map generateThumb

  def imageNameGen(imageKey: String, thumbSize: ThumbSize): String = imageKey + thumbSize.suffix + ".png"
  
  def generateThumb(thumbSize: ThumbSize): (File, String) = {
    val imageBuf = ImageIO.read(image)
    val height = imageBuf.getHeight
    val width = imageBuf.getWidth

    val imageName = imageNameGen(imageKey, thumbSize)

    if (width <= thumbSize.width && height <= thumbSize.height)
      (image, imageName)
    else {
      val (newWidth, newHeight) = ImageThumber.newSizesFor(thumbSize, width, height)
      (writeImage(newWidth, newHeight, imageBuf, thumbSize, imageName), imageName)
    }
  }

  private def writeImage(width: Int, height: Int, imageBuf: BufferedImage, thumbSize: ThumbSize, imageName: String) = {
    val scaledImage = new BufferedImage(width, height,  BufferedImage.TYPE_INT_RGB)
    val g = scaledImage.createGraphics
    g.setComposite(AlphaComposite.Src)
    g.drawImage(imageBuf, 0, 0, width, height, null);
    g.dispose

    val destFile = new File(image.getParentFile, imageName)
    ImageIO.write(scaledImage, "png", destFile)
    destFile
  }
}

object ImageThumber {
  val sizes = List(SmallThumb, MediumThumb, LargeThumb, VeryLargeThumb)

  def newSizesFor(thumbSize: ThumbSize, originalWidth: Int, originalHeight: Int): (Int, Int) = {
    var newWidth: Double = originalWidth
    var newHeight: Double = originalHeight

    if (newWidth > thumbSize.width){
      newWidth = thumbSize.width
      newHeight = originalHeight * newWidth / originalWidth
    }
    if (newHeight > thumbSize.height) {
      val oldHeight = newHeight
      newHeight = thumbSize.height
      newWidth = newHeight * newWidth / oldHeight
    }

    (newWidth.toInt, newHeight.toInt)
  }
}

sealed case class ThumbSize(width: Int, height: Int, suffix: String)
object SmallThumb extends ThumbSize(100, 100, "-small")
object MediumThumb extends ThumbSize(200, 200, "-medium")
object LargeThumb extends ThumbSize(300, 300, "-large")
object VeryLargeThumb extends ThumbSize(600, 600, "-verylarge")
object OriginalSize extends ThumbSize(0, 0, "")