Lua

Write Bytes to a Remote SFTP File (BinData)

Demonstrates the Chilkat SFtp.WriteFileBd method, which appends all bytes in a BinData to the remote file identified by an open handle. The first argument is the handle and the second is the BinData.

Note: This example uses a relative local path, which is resolved against the application's current working directory. Absolute local paths may also be used. Supply the path appropriate to your own environment.

Background: This is the binary counterpart to WriteFileText — the right choice for images, archives, or any non-text content, where a charset conversion would corrupt the data. Combined with an appropriate OpenFile disposition it can create, overwrite, or append; here the file is created/truncated first so the result is exactly the BinData contents.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the SFtp.WriteFileBd method, which appends all bytes in a BinData to the remote
-- file identified by an open handle.  The 1st argument is the handle and the 2nd is the BinData.

local sftp = chilkat.SFtp.new()

-- Connect, authenticate, and initialize the SFTP subsystem.
local port = 22
local success = sftp:connect("sftp.example.com", port)
if not success then
    print(sftp.last_error_text)
    return
end

-- 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.
local password = "mySshPassword"

success = sftp:authenticate_pw("mySshLogin", password)
if not success then
    print(sftp.last_error_text)
    return
end

success = sftp:initialize_sftp()
if not success then
    print(sftp.last_error_text)
    return
end

-- Open (creating/truncating) the remote file for writing.
local handle = sftp:open_file("subdir/image.png", "writeOnly", "createTruncate")
if not sftp.last_method_success then
    print(sftp.last_error_text)
    return
end

-- Put the bytes to write into a BinData.  (Here they are loaded from a local file, but the
-- bytes could come from anywhere.)
local bd = chilkat.BinData.new()
success = bd:load_file("qa_data/image.png")
if not success then
    print(bd.last_error_text)
    return
end

-- Append the BinData bytes to the open remote file.
success = sftp:write_file_bd(handle, bd)
if not success then
    print(sftp.last_error_text)
    return
end

success = sftp:close_handle(handle)
if not success then
    print(sftp.last_error_text)
    return
end

print("Wrote " .. bd.num_bytes .. " bytes.")

sftp:disconnect()