(Objective-C) Async SFTP Progress Info

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

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#import <CkoSFtp.h>
#import <NSString.h>
#import <CkoTask.h>

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

CkoSFtp *sftp = [[CkoSFtp alloc] init];

// Set some timeouts, in milliseconds:
sftp.ConnectTimeoutMs = [NSNumber numberWithInt:15000];
sftp.IdleTimeoutMs = [NSNumber numberWithInt:15000];

// Connect to the SFTP server.  
BOOL success = [sftp Connect: @"sftp.example.com" port: [NSNumber numberWithInt: 22]];
if (success != YES) {
    NSLog(@"%@",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" password: @"myPassword"];
if (success != YES) {
    NSLog(@"%@",sftp.LastErrorText);
    return;
}

// After authenticating, the SFTP subsystem must be initialized:
success = [sftp InitializeSftp];
if (success != YES) {
    NSLog(@"%@",sftp.LastErrorText);
    return;
}

// --------------------
// Download a file
// --------------------
NSString *localFilePath = @"c:/temp/hamlet.xml";
NSString *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.
CkoTask *task = [sftp DownloadFileByNameAsync: remoteFilePath localFilePath: localFilePath];
if (sftp.LastMethodSuccess == NO) {
    NSLog(@"%@",sftp.LastErrorText);
    return;
}

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

// Schedule the task for running on the thread pool.  This changes the task's state
// from Inert to Live.
success = [task Run];
if (success != YES) {
    NSLog(@"%@",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.
int curPctDone = 0;
NSString *name = 0;
NSString *value = 0;

while (task.Finished != YES) {

    if ([task.PercentDone intValue] != curPctDone) {
        curPctDone = [task.PercentDone intValue];
        NSLog(@"%d%@",curPctDone,@" percent done");
    }

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

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

        NSLog(@"%@%@%@",name,@": ",value);
        [task RemoveProgressInfo: [NSNumber numberWithInt: 0]];
    }

    // Sleep 100 ms.
    [task SleepMs: [NSNumber numberWithInt: 100]];

}

// Just in case there are any remaining entries...
while (([task.ProgressLogSize intValue] > 0)) {
    // Get the 1st entry, emit it, and then remove it..
    name = [task ProgressInfoName: [NSNumber numberWithInt: 0]];
    value = [task ProgressInfoValue: [NSNumber numberWithInt: 0]];
    NSLog(@"%@%@%@",name,@": ",value);
    [task RemoveProgressInfo: [NSNumber numberWithInt: 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 intValue] != 7) {
    NSLog(@"%@",@"Task did not complete.");
    NSLog(@"%@%@",@"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 != YES) {
    // The task's ResultErrorText contains what would have been in the LastErrorText property had
    // the DownloadFileByName method been called synchronously.
    NSLog(@"%@",task.ResultErrorText);
}
else {
    NSLog(@"%@",@"File downloaded asynchronously.");
}