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SFTP Upload Large File in Parts

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Demonstrates how to split a large file into N parts and then upload each part separately. This technique can be used to potentially avoid limits a SFTP server might impose on upload file size. AutoIt

Local $bSuccess = False

; This example assumes the Chilkat API to have been previously unlocked.
; See Global Unlock Sample for sample code.

$oSftp = ObjCreate("Chilkat.SFtp")

; Set some timeouts, in milliseconds:
$oSftp.ConnectTimeoutMs = 5000
$oSftp.IdleTimeoutMs = 10000

; Connect to the SSH server.  
; The standard SSH port = 22
; The hostname may be a hostname or IP address.
Local $sHostname = "sftp.example.com"
Local $iPort = 22
$bSuccess = $oSftp.Connect($sHostname,$iPort)
If ($bSuccess <> True) Then
    ConsoleWrite($oSftp.LastErrorText & @CRLF)
    Exit
EndIf

; Authenticate with the SSH server.  Chilkat SFTP supports
; both password-based authenication as well as public-key
; authentication.  This example uses password authenication.
$bSuccess = $oSftp.AuthenticatePw("myLogin","myPassword")
If ($bSuccess <> True) Then
    ConsoleWrite($oSftp.LastErrorText & @CRLF)
    Exit
EndIf

; After authenticating, the SFTP subsystem must be initialized:
$bSuccess = $oSftp.InitializeSftp()
If ($bSuccess <> True) Then
    ConsoleWrite($oSftp.LastErrorText & @CRLF)
    Exit
EndIf

; Open a remote file for writing on the SSH server.
; If the file already exists, it is overwritten.
; (Specify "createNew" instead of "createTruncate" to
; prevent overwriting existing files.)
Local $sHandle = $oSftp.OpenFile("big.zip","writeOnly","createTruncate")
If ($oSftp.LastMethodSuccess <> True) Then
    ConsoleWrite($oSftp.LastErrorText & @CRLF)
    Exit
EndIf

; We're going to upload the local file "qa_data/zips/big.zip" (a relative local path from our current working directory)
; to the SFTP server.
Local $sLocalFilePath = "qa_data/zips/big.zip"

; Rather than uploading in one shot, we'll read the local file in chunks
; and upload a chunk at a time.
$oFac = ObjCreate("Chilkat.FileAccess")

$bSuccess = $oFac.OpenForRead($sLocalFilePath)
If ($bSuccess = False) Then
    $oSftp.CloseHandle($sHandle)
    ConsoleWrite($oFac.LastErrorText & @CRLF)
    Exit
EndIf

; If we were to split the local file into 128K chunks, how many chunks (blocks) would
; we have, including the last partial block?
Local $iBlockSize = 131072
Local $iNumBlocks = $oFac.GetNumBlocks($iBlockSize)
ConsoleWrite("Number of blocks = " & $iNumBlocks & @CRLF)

$oBd = ObjCreate("Chilkat.BinData")
Local $i = 0
While $i < $iNumBlocks
    ; Read the Nth block, which gets appended to the bd.  (which means
    ; we must clear the contents of bd before the next iteration)
    $bSuccess = $oFac.ReadBlockBd($i,$iBlockSize,$oBd)
    If ($bSuccess = False) Then
        $oSftp.CloseHandle($sHandle)
        ConsoleWrite($oFac.LastErrorText & @CRLF)
        Exit
    EndIf

    ; Upload this block to the open remote file.
    $bSuccess = $oSftp.WriteFileBd($sHandle,$oBd)
    If ($bSuccess = False) Then
        ConsoleWrite($oSftp.LastErrorText & @CRLF)
        Exit
    EndIf

    ; Clear the contents for the next iteration.
    $oBd.Clear()

    $i = $i + 1
Wend

; Close the local file.
$oFac.FileClose 

; -----------------------------------------------------------------------------
; This is important.  You must close the handle on the server.
; Otherwise open handles will accumulate on the server until eventually a limit
; is reached and the server will fail on a call to OpenFile.
; -----------------------------------------------------------------------------

; Close the remote file handle on the server.
$bSuccess = $oSftp.CloseHandle($sHandle)
If ($bSuccess <> True) Then
    ConsoleWrite($oSftp.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite("Success." & @CRLF)