Using SSIS Script Task to download files from FTP - vb.net

Question

I am trying to download files from FTP using SSIS script task, I have written some code to download files from FTP using the ftpWebRequest class which is working. But I also need to take in to account that we might be asked to download it from a sFTP. Since many are suggesting that WinSCP assemblies are the best way to download sFTP files, can some provide me with some examples to download files using a SSIS script with the WinSCP classes.
PS: I am new to Vb.net

Answer 1

Yes, as people have said the only option is to use a library like WinSCP.
Take a look at the examples here on the WinSCP website - http://winscp.net/eng/docs/script_vbnet_robust_example
Here is the source code from the example
Imports System
Imports System.IO
Imports System.Diagnostics
Imports System.Xml
Imports System.Xml.XPath
Imports System.Configuration.ConfigurationManager
Public Class SFTP
' SFTP support, built on WinSCP
Public Shared Function PutSFTP(ByRef filename As String, ByRef remotehost As String, ByRef username As String, ByRef password As String, _
Optional ByVal outfilename As String = Nothing, Optional ByVal output As String = Nothing,
Optional ByRef errmsg As String = Nothing) As Boolean
' Run hidden WinSCP process
Dim winscp As Process = New Process()
Dim logname As String = Path.ChangeExtension(Path.GetTempFileName, "xml")
With winscp.StartInfo
' SFTPExecutable needs to be defined in app.config to point to winscp.com
Try
.FileName = AppSettings("SFTPExecutable")
If .FileName Is Nothing OrElse .FileName.Length = 0 Then Throw (New Exception("from PutSFTP: SFTPExecutable not set in config file."))
Catch ex As Exception
errmsg = ex.Message
Return False
End Try
.Arguments = "/xmllog=" + logname
.UseShellExecute = False
.RedirectStandardInput = True
.RedirectStandardOutput = True
.CreateNoWindow = True
End With
Try
winscp.Start()
Catch ex As Exception
errmsg = "from PutSFTP: Could not run the WinSCP executable " & winscp.StartInfo.FileName & Environment.NewLine & ex.Message
Return False
End Try
' Feed in the scripting commands
With winscp.StandardInput
.WriteLine("option batch abort")
.WriteLine("option confirm off")
.WriteLine("open sftp://" & username & ":" & password & "#" & remotehost & "/")
If outfilename Is Nothing Then .WriteLine("put " & filename) Else .WriteLine("put " & filename & " """ & outfilename & """")
.Close()
End With
If output IsNot Nothing Then output = winscp.StandardOutput.ReadToEnd()
' Wait until WinSCP finishes
winscp.WaitForExit()
' Parse and interpret the XML log
' (Note that in case of fatal failure the log file may not exist at all)
If Not File.Exists(logname) Then
errmsg = "from PutSFTP: The WinSCP executable appears to have crashed."
Return False
End If
Dim log As XPathDocument = New XPathDocument(logname)
Dim ns As XmlNamespaceManager = New XmlNamespaceManager(New NameTable())
ns.AddNamespace("w", "http://winscp.net/schema/session/1.0")
Dim nav As XPathNavigator = log.CreateNavigator()
' Success (0) or error?
Dim status As Boolean = (winscp.ExitCode = 0)
If Not status Then
errmsg = "from PutSFTP: There was an error transferring " & filename & "."
' See if there are any messages associated with the error
For Each message As XPathNavigator In nav.Select("//w:message", ns)
errmsg &= Environment.NewLine & message.Value
Next message
End If
Try
My.Computer.FileSystem.DeleteFile(logname)
Catch ex As Exception
' at least we tried to clean up
End Try
Return status
End Function
End Class