Data commit

Task/FTP/Scala/ftp.scala

@@ -0,0 +1,78 @@
+import java.io.{File, FileOutputStream, InputStream}
+
+import org.apache.commons.net.ftp.{FTPClient, FTPFile, FTPReply}
+
+import scala.util.{Failure, Try}
+
+object FTPconn extends App {
+  val (server, pass) = ("ftp.ed.ac.uk", "-ftptest@example.com")
+  val (dir, filename, ftpClient) = ("/pub/cartonet/", "readme.txt", new FTPClient())
+
+  def canConnect(host: String): Boolean = {
+    ftpClient.connect(host)
+    val connectionWasEstablished = ftpClient.isConnected
+    ftpClient.disconnect()
+    connectionWasEstablished
+  }
+
+  def downloadFileStream(remote: String): InputStream = {
+    val stream: InputStream = ftpClient.retrieveFileStream(remote)
+    ftpClient.completePendingCommand()
+    stream
+  }
+
+  def uploadFile(remote: String, input: InputStream): Boolean = ftpClient.storeFile(remote, input)
+
+  if (Try {
+    def cwd(path: String): Boolean = ftpClient.changeWorkingDirectory(path)
+
+    def filesInCurrentDirectory: Seq[String] = listFiles().map(_.getName)
+
+    def listFiles(): List[FTPFile] = ftpClient.listFiles.toList
+
+    def downloadFile(remote: String): Boolean = {
+      val os = new FileOutputStream(new File(remote))
+      ftpClient.retrieveFile(remote, os)
+    }
+
+    def connectWithAuth(host: String,
+                        password: String,
+                        username: String = "anonymous",
+                        port: Int = 21): Try[Boolean] = {
+      def connect(): Try[Unit] = Try {
+        try {
+          ftpClient.connect(host, port)
+        } catch {
+          case ex: Throwable =>
+            println(ex.getMessage)
+            Failure
+        }
+        ftpClient.enterLocalPassiveMode()
+        serverReply(ftpClient)
+
+        val replyCode = ftpClient.getReplyCode
+        if (!FTPReply.isPositiveCompletion(replyCode))
+          println("Failure. Server reply code: " + replyCode)
+      }
+
+      for {
+        connection <- connect()
+        login <- Try {
+          ftpClient.login(username, password)
+        }
+      } yield login
+    }
+
+    def serverReply(ftpClient: FTPClient): Unit =
+      for (reply <- ftpClient.getReplyStrings) println(reply)
+
+    connectWithAuth(server, pass)
+
+    cwd(dir)
+    listFiles().foreach(println)
+
+    downloadFile(filename)
+    serverReply(ftpClient)
+    ftpClient.logout
+  }.isFailure) println(s"Failure.")
+}