(Xojo Plugin) Async SFTP Progress Info

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

Chilkat Xojo Plugin Download Xojo Plugin for Windows, Linux, Mac OS X, and ARM, ARM64

// All Chilkat classes can be unlocked at once at the beginning of a program
// by calling UnlockBundle.  It requires a Bundle unlock code.
Dim chilkatGlob As New Chilkat.CkGlobal
Dim success As Boolean
success = chilkatGlob.UnlockBundle("Anything for 30-day trial.")
If (success <> True) Then
    System.DebugLog(chilkatGlob.LastErrorText)
    Return
End If

Dim sftp As New Chilkat.SFtp

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

// Connect to the SSH server.  
// The standard SSH port = 22
// The hostname may be a hostname or IP address.
Dim hostname As String
hostname = "www.my-ssh-server.com"
Dim port As Int32
port = 22
success = sftp.Connect(hostname,port)
If (success <> True) Then
    System.DebugLog(sftp.LastErrorText)
    Return
End If

// 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) Then
    System.DebugLog(sftp.LastErrorText)
    Return
End If

// After authenticating, the SFTP subsystem must be initialized:
success = sftp.InitializeSftp()
If (success <> True) Then
    System.DebugLog(sftp.LastErrorText)
    Return
End If

// --------------------
// Download a file
// --------------------
Dim localFilePath As String
localFilePath = "c:/temp/hamlet.xml"
Dim remoteFilePath As String
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.
Dim task As Chilkat.Task
task = sftp.DownloadFileByNameAsync(remoteFilePath,localFilePath)
If (sftp.LastMethodSuccess = False) Then
    System.DebugLog(sftp.LastErrorText)
    Return
End If

// 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) Then
    System.DebugLog(task.LastErrorText)

    Return
End If

// 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.
Dim curPctDone As Int32
curPctDone = 0
Dim name As String
Dim value As String

While task.Finished <> True

    If (task.PercentDone <> curPctDone) Then
        curPctDone = task.PercentDone
        System.DebugLog(Str(curPctDone) + " percent done")
    End If

    // 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"

        System.DebugLog(name + ": " + value)
        task.RemoveProgressInfo 0
    Wend

    // Sleep 100 ms.
    task.SleepMs 100

Wend

// 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)
    System.DebugLog(name + ": " + value)
    task.RemoveProgressInfo 0
Wend

// 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) Then
    System.DebugLog("Task did not complete.")
    System.DebugLog("task status: " + task.Status)

    Return
End If

// 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) Then
    // The task's ResultErrorText contains what would have been in the LastErrorText property had
    // the DownloadFileByName method been called synchronously.
    System.DebugLog(task.ResultErrorText)
Else
    System.DebugLog("File downloaded asynchronously.")
End If