UserVoiceTokenGenerator.scala

// Based on Andrew Conner's example at https://gist.github.com/andrewconner/5510961
import org.apache.commons.codec.net.URLCodec
import org.apache.commons.codec.binary.Base64
import javax.crypto.spec.SecretKeySpec
import javax.crypto.spec.IvParameterSpec
import org.apache.commons.codec.digest.DigestUtils
import java.io.InputStream
import java.io.OutputStream
import javax.crypto.Cipher
import javax.crypto.CipherOutputStream
import java.io.ByteArrayOutputStream
import java.io.ByteArrayInputStream

object UserVoiceTokenGenerator  {
  private final val USERVOICE_SUBDOMAIN = "<insert UserVoice subdomain>"
  private final val SSO_KEY = "<insert UserVoice SSO key>"
  private final val INIT_VECTOR = "OpenSSL for Ruby".getBytes()
  private val hash = DigestUtils.sha(SSO_KEY + USERVOICE_SUBDOMAIN).toSeq
  
  private val secretKeySpec = new SecretKeySpec(hash.take(16).toArray, "AES")
  private val ivSpec = new IvParameterSpec(INIT_VECTOR)
  private val urlCodec = new URLCodec("ASCII")
  private val base64 = new Base64()
  
  private def encrypt(in: InputStream): ByteArrayOutputStream = {
    val cipher = Cipher.getInstance("AES/CBC/PKCS5Padding")
    cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivSpec)
    val buf = new Array[Byte](1024)
    
    val byteStream = new ByteArrayOutputStream()
    val out = new CipherOutputStream(byteStream, cipher)
    try {
      Iterator.continually(in.read(buf)).takeWhile(_ >= 0) foreach { numRead =>
        out.write(buf, 0, numRead)
      }
    } catch {
      case ex: Throwable =>
        // integrate your application logging
        ex.printStackTrace()
    } finally {
      out.close()
    }
    byteStream
  }
  
  def create(json: String): String = {
    val jsonBytes = json.getBytes() 
    val data = INIT_VECTOR.zip(jsonBytes).take(16).map({ case (i, d) => (i ^ d).byteValue }) ++ jsonBytes.drop(INIT_VECTOR.length)
    val out = encrypt(new ByteArrayInputStream(data));

    new String(urlCodec.encode(base64.encode(out.toByteArray)))
  }
}