JavaScript

Monitor FTP Transfer Progress

Demonstrates the progress properties CurBytesReceived, CurBytesReceivedStr, CurBytesSent, CurBytesSentStr, ProgressMonSize, PercentDoneScale, and AutoGetSizeForProgress.

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: Percentage progress needs a known total, but FTP does not always report a file's size up front — so AutoGetSizeForProgress issues a SIZE command before a download, and ProgressMonSize supplies an expected size when even that is unavailable (a one-shot value consumed by the next transfer). PercentDoneScale sets the resolution of progress callbacks. The current byte counts are exposed both as 32-bit integers and as strings, the string forms avoiding integer-width limits for very large transfers.

Note

This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.

JavaScript

var success = false;

var ftp = new CkFtp2();

ftp.Hostname = "ftp.example.com";
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.
ftp.Password = "myPassword";

success = ftp.Connect();
if (success == false) {
    console.log(ftp.LastErrorText);
    return;
}

//  AutoGetSizeForProgress sends a SIZE command before a download so percentage-based progress can
//  be computed.
ftp.AutoGetSizeForProgress = true;

//  PercentDoneScale sets the value representing one hundred percent in PercentDone callbacks.
//  1000 gives tenth-of-a-percent resolution.
ftp.PercentDoneScale = 1000;

//  ProgressMonSize is a one-shot expected size for the next download when the size is not
//  otherwise known.  It is consumed by the next download and reset to 0.
ftp.ProgressMonSize = 20485760;

success = ftp.GetFile("public_html/bigfile.zip","qa_output/bigfile.zip");
if (success == false) {
    console.log(ftp.LastErrorText);
    return;
}

//  After a transfer, the current byte counts are available as 32-bit numbers or as strings (the
//  string forms avoid integer-size limits).
console.log("Bytes received: " + ftp.CurBytesReceived);
console.log("Bytes received (str): " + ftp.CurBytesReceivedStr);
console.log("Bytes sent: " + ftp.CurBytesSent);
console.log("Bytes sent (str): " + ftp.CurBytesSentStr);

success = ftp.Disconnect();
if (success == false) {
    console.log(ftp.LastErrorText);
    return;
}