PowerBuilder

Upload a Large File in Chunks (FTP)

Demonstrates the Chilkat Ftp2.LargeFileUpload method, which uploads a local file as a sequence of transfers, each up to a given chunk size. The arguments are the local path, the remote path, and the chunk size in bytes.

Note: The local paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: Some servers, proxies, or firewalls impose a limit on the size or duration of a single data transfer, which a very large file can exceed. This method sidesteps that by sending the file in pieces — the first with STOR to create or replace the file, each subsequent one appended — so no single transfer is oversized. Choose a chunk size comfortably under whatever limit you are working around.

Chilkat PowerBuilder Downloads

Download Chilkat for PowerBuilder

PowerBuilder

integer li_rc
integer li_Success
oleobject loo_Ftp
integer li_ChunkSize

li_Success = 0

//  Demonstrates the Ftp2.LargeFileUpload method, which uploads a local file as a sequence of
//  transfers, each up to a given chunk size.  The 1st argument is the local path, the 2nd is the
//  remote path, and the 3rd is the chunk size in bytes.

loo_Ftp = create oleobject
li_rc = loo_Ftp.ConnectToNewObject("Chilkat.Ftp2")
if li_rc < 0 then
    destroy loo_Ftp
    MessageBox("Error","Connecting to COM object failed")
    return
end if

loo_Ftp.Hostname = "ftp.example.com"
loo_Ftp.Username = "myFtpLogin"

//  Normally you would not hard-code the password in source.  You should instead obtain it
//  from an interactive prompt, environment variable, or a secrets vault.
loo_Ftp.Password = "myPassword"

li_Success = loo_Ftp.Connect()
if li_Success = 0 then
    Write-Debug loo_Ftp.LastErrorText
    destroy loo_Ftp
    return
end if

//  The first chunk is sent with STOR (creating/replacing the remote file); each later chunk is
//  appended.  Uploading in chunks can work around server or network limits on a single transfer.
li_ChunkSize = 10485760
li_Success = loo_Ftp.LargeFileUpload("qa_data/bigfile.zip","uploads/bigfile.zip",li_ChunkSize)
if li_Success = 0 then
    Write-Debug loo_Ftp.LastErrorText
    destroy loo_Ftp
    return
end if

Write-Debug "Large file uploaded."

li_Success = loo_Ftp.Disconnect()
if li_Success = 0 then
    Write-Debug loo_Ftp.LastErrorText
    destroy loo_Ftp
    return
end if



destroy loo_Ftp