(DataFlex) 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.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-9.5.0-win32.pkg

Procedure Test
    Handle hoChilkatGlob
    Boolean iSuccess
    Handle hoSftp
    Integer iWaitMaxMs
    Integer iPort
    String sHostname
    Variant vTask
    Handle hoTask
    String sRemoteFilePath
    String sLocalFilePath
    String sTemp1
    Integer iTemp1
    Boolean bTemp1

    // All Chilkat classes can be unlocked at once at the beginning of a program
    // by calling UnlockBundle.  It requires a Bundle unlock code.
    Get Create (RefClass(cComChilkatGlobal)) To hoChilkatGlob
    If (Not(IsComObjectCreated(hoChilkatGlob))) Begin
        Send CreateComObject of hoChilkatGlob
    End
    Get ComUnlockBundle Of hoChilkatGlob "Anything for 30-day trial." To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoChilkatGlob To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get Create (RefClass(cComChilkatSFtp)) To hoSftp
    If (Not(IsComObjectCreated(hoSftp))) Begin
        Send CreateComObject of hoSftp
    End

    // Set some timeouts, in milliseconds:
    Set ComConnectTimeoutMs Of hoSftp To 15000
    Set ComIdleTimeoutMs Of hoSftp To 15000
    Move 30000 To iWaitMaxMs

    // Connect to the SSH server.  
    // The standard SSH port = 22
    // The hostname may be a hostname or IP address.
    Move 22 To iPort
    Move "www.my-ssh-server.com" To sHostname

    Get ComConnectAsync Of hoSftp sHostname iPort To vTask
    If (IsComObject(vTask)) Begin
        Get Create (RefClass(cComChilkatTask)) To hoTask
        Set pvComObject Of hoTask To vTask
    End
    Get ComLastMethodSuccess Of hoSftp To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoSftp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Start the background task.
    Get ComRun Of hoTask To iSuccess
    If (Not iSuccess) Begin
        Get ComLastErrorText Of hoTask To sTemp1
        Showln sTemp1
    End

    // Wait for the connect task to finish.
    // The True/False returned by Wait applies to the Wait method call, not the task.
    Get ComWait Of hoTask iWaitMaxMs To iSuccess
    Get ComStatusInt Of hoTask To iTemp1
    Get ComTaskSuccess Of hoTask To bTemp1
    If (Not iSuccess Or (iTemp1 <> 7) Or (bTemp1 <> True)) Begin
        If (Not iSuccess) Begin
            // The task.LastErrorText applies to the Wait method call.
            Get ComLastErrorText Of hoTask To sTemp1
            Showln sTemp1
        End
        Else Begin
            // The ResultErrorText applies to the underlying task method call (i.e. the Connect)
            Get ComStatus Of hoTask To sTemp1
            Showln sTemp1
            Get ComResultErrorText Of hoTask To sTemp1
            Showln sTemp1
        End

        Send Destroy of hoTask
        Procedure_Return
    End

    Send Destroy of hoTask

    // Authenticate with the SSH server.  Chilkat SFTP supports
    // both password-based authenication as well as public-key
    // authentication.  This example uses password authenication.
    Get ComAuthenticatePwAsync Of hoSftp "myLogin" "myPassword" To vTask
    If (IsComObject(vTask)) Begin
        Get Create (RefClass(cComChilkatTask)) To hoTask
        Set pvComObject Of hoTask To vTask
    End
    // To keep the example short, we'll skip handling failures.
    // The failures would be handled in the same way as shown above.

    Get ComRun Of hoTask To iSuccess
    Get ComWait Of hoTask iWaitMaxMs To iSuccess
    Send Destroy of hoTask

    // After authenticating, the SFTP subsystem must be initialized:
    Get ComInitializeSftpAsync Of hoSftp To vTask
    If (IsComObject(vTask)) Begin
        Get Create (RefClass(cComChilkatTask)) To hoTask
        Set pvComObject Of hoTask To vTask
    End
    Get ComRun Of hoTask To iSuccess
    Get ComWait Of hoTask iWaitMaxMs To iSuccess
    Send Destroy of hoTask

    // Upload from the local file to the SSH server.
    // Important -- the remote filepath is the 1st argument,
    // the local filepath is the 2nd argument;
    Move "hamlet.xml" To sRemoteFilePath
    Move "c:/temp/hamlet.xml" To sLocalFilePath

    Get ComUploadFileByNameAsync Of hoSftp sRemoteFilePath sLocalFilePath To vTask
    If (IsComObject(vTask)) Begin
        Get Create (RefClass(cComChilkatTask)) To hoTask
        Set pvComObject Of hoTask To vTask
    End
    Get ComLastMethodSuccess Of hoSftp To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoSftp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComRun Of hoTask To iSuccess
    Get ComWait Of hoTask iWaitMaxMs To iSuccess
    Get ComStatusInt Of hoTask To iTemp1
    Get ComTaskSuccess Of hoTask To bTemp1
    If (Not iSuccess Or (iTemp1 <> 7) Or (bTemp1 <> True)) Begin
        If (Not iSuccess) Begin
            // The task.LastErrorText applies to the Wait method call.
            Get ComLastErrorText Of hoTask To sTemp1
            Showln sTemp1
        End
        Else Begin
            // The ResultErrorText applies to the underlying task method call (i.e. the Connect)
            Get ComStatus Of hoTask To sTemp1
            Showln sTemp1
            Get ComResultErrorText Of hoTask To sTemp1
            Showln sTemp1
        End

        Send Destroy of hoTask
        Procedure_Return
    End

    Send Destroy of hoTask
    Showln "File uploaded."


End_Procedure