(Perl) SFTP Upload Large File in Parts

See more SFTP Examples

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.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

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

$sftp = chilkat::CkSFtp->new();

# Set some timeouts, in milliseconds:
$sftp->put_ConnectTimeoutMs(5000);
$sftp->put_IdleTimeoutMs(10000);

# Connect to the SSH server.  
# The standard SSH port = 22
# The hostname may be a hostname or IP address.
$hostname = "sftp.example.com";
$port = 22;
$success = $sftp->Connect($hostname,$port);
if ($success != 1) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

# Authenticate with the SSH server.  Chilkat SFTP supports
# both password-based authenication as well as public-key
# authentication.  This example uses password authenication.
$success = $sftp->AuthenticatePw("myLogin","myPassword");
if ($success != 1) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

# After authenticating, the SFTP subsystem must be initialized:
$success = $sftp->InitializeSftp();
if ($success != 1) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

# 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.)
$handle = $sftp->openFile("big.zip","writeOnly","createTruncate");
if ($sftp->get_LastMethodSuccess() != 1) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

# 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.
$localFilePath = "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.
$fac = chilkat::CkFileAccess->new();

$success = $fac->OpenForRead($localFilePath);
if ($success == 0) {
    $sftp->CloseHandle($handle);
    print $fac->lastErrorText() . "\r\n";
    exit;
}

# If we were to split the local file into 128K chunks, how many chunks (blocks) would
# we have, including the last partial block?
$blockSize = 131072;
$numBlocks = $fac->GetNumBlocks($blockSize);
print "Number of blocks = " . $numBlocks . "\r\n";

$bd = chilkat::CkBinData->new();
$i = 0;
while ($i < $numBlocks) {
    # Read the Nth block, which gets appended to the bd.  (which means
    # we must clear the contents of bd before the next iteration)
    $success = $fac->ReadBlockBd($i,$blockSize,$bd);
    if ($success == 0) {
        $sftp->CloseHandle($handle);
        print $fac->lastErrorText() . "\r\n";
        exit;
    }

    # Upload this block to the open remote file.
    $success = $sftp->WriteFileBd($handle,$bd);
    if ($success == 0) {
        print $sftp->lastErrorText() . "\r\n";
        exit;
    }

    # Clear the contents for the next iteration.
    $bd->Clear();

    $i = $i + 1;
}

# Close the local file.
$fac->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.
$success = $sftp->CloseHandle($handle);
if ($success != 1) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

print "Success." . "\r\n";