(PureBasic) Wait for Async Method to Complete

Demonstrates using the Wait method to wait for an asynchronous method to complete. This example will do an SFTP upload (over SSH) and will use the Async version of each method. Obviously, waiting for the async method to complete is the same as making a synchronous call, but an application wouldn't typically do this. An application might, for example, do other things as a background task is running, and then later wait for the task to complete.

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IncludeFile "CkTask.pb"
IncludeFile "CkGlobal.pb"
IncludeFile "CkSFtp.pb"

Procedure ChilkatExample()

    ; All Chilkat classes can be unlocked at once at the beginning of a program
    ; by calling UnlockBundle.  It requires a Bundle unlock code.
    chilkatGlob.i = CkGlobal::ckCreate()
    If chilkatGlob.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success.i = CkGlobal::ckUnlockBundle(chilkatGlob,"Anything for 30-day trial.")
    If success <> 1
        Debug CkGlobal::ckLastErrorText(chilkatGlob)
        CkGlobal::ckDispose(chilkatGlob)
        ProcedureReturn
    EndIf

    sftp.i = CkSFtp::ckCreate()
    If sftp.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Set some timeouts, in milliseconds:
    CkSFtp::setCkConnectTimeoutMs(sftp, 15000)
    CkSFtp::setCkIdleTimeoutMs(sftp, 15000)
    waitMaxMs.i = 30000

    ; Connect to the SSH server.  
    ; The standard SSH port = 22
    ; The hostname may be a hostname or IP address.
    port.i = 22
    hostname.s = "www.my-ssh-server.com"

    task.i = CkSFtp::ckConnectAsync(sftp,hostname,port)
    If CkSFtp::ckLastMethodSuccess(sftp) = 0
        Debug CkSFtp::ckLastErrorText(sftp)
        CkGlobal::ckDispose(chilkatGlob)
        CkSFtp::ckDispose(sftp)
        ProcedureReturn
    EndIf

    ; Start the background task.
    success = CkTask::ckRun(task)
    If Not success
        Debug CkTask::ckLastErrorText(task)
    EndIf

    ; Wait for the connect task to finish.
    ; The 1/0 returned by Wait applies to the Wait method call, not the task.
    success = CkTask::ckWait(task,waitMaxMs)
    If Not success OR (CkTask::ckStatusInt(task) <> 7) OR (CkTask::ckTaskSuccess(task) <> 1)
        If Not success
            ; The task.LastErrorText applies to the Wait method call.
            Debug CkTask::ckLastErrorText(task)
        Else
            ; The ResultErrorText applies to the underlying task method call (i.e. the Connect)
            Debug CkTask::ckStatus(task)
            Debug CkTask::ckResultErrorText(task)
        EndIf

        CkTask::ckDispose(task)

        CkGlobal::ckDispose(chilkatGlob)
        CkSFtp::ckDispose(sftp)
        ProcedureReturn
    EndIf

    CkTask::ckDispose(task)

    ; Authenticate with the SSH server.  Chilkat SFTP supports
    ; both password-based authenication as well as public-key
    ; authentication.  This example uses password authenication.
    task = CkSFtp::ckAuthenticatePwAsync(sftp,"myLogin","myPassword")
    ; To keep the example short, we'll skip handling failures.
    ; The failures would be handled in the same way as shown above.

    success = CkTask::ckRun(task)
    success = CkTask::ckWait(task,waitMaxMs)
    CkTask::ckDispose(task)

    ; After authenticating, the SFTP subsystem must be initialized:
    task = CkSFtp::ckInitializeSftpAsync(sftp)
    success = CkTask::ckRun(task)
    success = CkTask::ckWait(task,waitMaxMs)
    CkTask::ckDispose(task)

    ; Upload from the local file to the SSH server.
    ; Important -- the remote filepath is the 1st argument,
    ; the local filepath is the 2nd argument;
    remoteFilePath.s = "hamlet.xml"
    localFilePath.s = "c:/temp/hamlet.xml"

    task = CkSFtp::ckUploadFileByNameAsync(sftp,remoteFilePath,localFilePath)
    If CkSFtp::ckLastMethodSuccess(sftp) = 0
        Debug CkSFtp::ckLastErrorText(sftp)
        CkGlobal::ckDispose(chilkatGlob)
        CkSFtp::ckDispose(sftp)
        ProcedureReturn
    EndIf

    success = CkTask::ckRun(task)
    success = CkTask::ckWait(task,waitMaxMs)
    If Not success OR (CkTask::ckStatusInt(task) <> 7) OR (CkTask::ckTaskSuccess(task) <> 1)
        If Not success
            ; The task.LastErrorText applies to the Wait method call.
            Debug CkTask::ckLastErrorText(task)
        Else
            ; The ResultErrorText applies to the underlying task method call (i.e. the Connect)
            Debug CkTask::ckStatus(task)
            Debug CkTask::ckResultErrorText(task)
        EndIf

        CkTask::ckDispose(task)

        CkGlobal::ckDispose(chilkatGlob)
        CkSFtp::ckDispose(sftp)
        ProcedureReturn
    EndIf

    CkTask::ckDispose(task)

    Debug "File uploaded."


    CkGlobal::ckDispose(chilkatGlob)
    CkSFtp::ckDispose(sftp)


    ProcedureReturn
EndProcedure