Node.js

Async SFTP Progress Info

See more SFTP Examples

Demonstrates checking for progress info updates when running a task asynchronously. This example demonstrates an SFTP download. Node.js

NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

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

    var sftp = new chilkat.SFtp();

    //  Set some timeouts, in milliseconds:
    sftp.ConnectTimeoutMs = 15000;
    sftp.IdleTimeoutMs = 15000;

    //  Connect to the SFTP server.  
    success = sftp.Connect("sftp.example.com",22);
    if (success !== true) {
        console.log(sftp.LastErrorText);
        return;
    }

    //  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 !== true) {
        console.log(sftp.LastErrorText);
        return;
    }

    //  After authenticating, the SFTP subsystem must be initialized:
    success = sftp.InitializeSftp();
    if (success !== true) {
        console.log(sftp.LastErrorText);
        return;
    }

    //  --------------------
    //  Download a file
    //  --------------------
    var localFilePath = "c:/temp/hamlet.xml";
    var remoteFilePath = "subdir1/subdir2/hamlet.xml";

    //  Call the async version of the DownloadFileByName method to return a task object.
    //  The task object is loaded, but is in the Inert state -- meaning it is
    //  not yet scheduled to run on Chilkat's background thread pool.
    // task: Task
    var task = sftp.DownloadFileByNameAsync(remoteFilePath,localFilePath);
    if (sftp.LastMethodSuccess == false) {
        console.log(sftp.LastErrorText);
        return;
    }

    //  Before starting the task, tell it to keep an in-memory log of what would've been
    //  ProgressInfo callbacks.
    task.KeepProgressLog = true;

    //  Schedule the task for running on the thread pool.  This changes the task's state
    //  from Inert to Live.
    success = task.Run();
    if (success !== true) {
        console.log(task.LastErrorText);

        return;
    }

    //  The application is now free to do anything else
    //  while the file is being downloaded.

    //  For this example, we'll simply sleep and periodically
    //  check to see if the download is finished, and report the progress
    //  along the way.
    var curPctDone = 0;
    var name;
    var value;

    while (task.Finished !== true) {

        if (task.PercentDone !== curPctDone) {
            curPctDone = task.PercentDone;
            console.log(curPctDone + " percent done");
        }

        //  Check the progress info log.
        //  Emit any log entries..
        while ((task.ProgressLogSize > 0)) {
            //  Get the 1st entry, emit it, and then remove it..
            name = task.ProgressInfoName(0);
            value = task.ProgressInfoValue(0);

            //  Entries reporting the received byte count will have the name "RcvByteCount"
            //  Entries reporting the current bytes-per-second will have the name "RcvBytesPerSec"

            console.log(name + ": " + value);
            task.RemoveProgressInfo(0);
        }

        //  Sleep 100 ms.
        task.SleepMs(100);

    }

    //  Just in case there are any remaining entries...
    while ((task.ProgressLogSize > 0)) {
        //  Get the 1st entry, emit it, and then remove it..
        name = task.ProgressInfoName(0);
        value = task.ProgressInfoValue(0);
        console.log(name + ": " + value);
        task.RemoveProgressInfo(0);
    }

    //  A finished task could be one that was canceled, aborted, or truly finished.  

    //  If the task was "canceled", it was canceled prior to actually starting.  This could
    //  happen if the task was canceled while waiting in a thread pool queue to be scheduled by Chilkat's
    //  background thread pool scheduler.  

    //  If the task was "aborted", it indicates that it was canceled while running in a background thread.  
    //  The ResultErrorText will likely indicate that the task was aborted.

    //  If the task "completed", then it ran to completion, but the actual success/failure of the method
    //  is determined by the result obtained via a GetResult* method.  (A "completed" task will
    //  have a StatusInt equal to 7.   If the task finished, but was not completed, then it must've
    //  been aborted or canceled:
    if (task.StatusInt !== 7) {
        console.log("Task did not complete.");
        console.log("task status: " + task.Status);

        return;
    }

    //  The DownloadFileByName method returns a boolean.  Therefore, after the task is finished,
    //  we can get the boolean result by calling GetResultBool.  This is the return value had
    //  we called DownloadFileByName synchronously.
    success = task.GetResultBool();
    if (success !== true) {
        //  The task's ResultErrorText contains what would have been in the LastErrorText property had
        //  the DownloadFileByName method been called synchronously.
        console.log(task.ResultErrorText);
    }
    else {
        console.log("File downloaded asynchronously.");
    }


}

chilkatExample();