SSH Remote Shell with Multiple Commands

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Demonstrates running several commands one after another in a single remote shell session, retrieving each command's output separately. No PTY is requested, so each command is followed by an echoed marker that signals where its output ends.

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @iTmp0 int
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

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

    --  Demonstrates running several commands one after another in a single remote shell session,
    --  retrieving each command's output separately.
    --  
    --  No PTY is requested, so the shell runs non-interactively and never prints a command prompt.
    --  Because there is no prompt to synchronize on, each command is followed by an "echo" of a
    --  unique marker, and the output is read up to that marker.

    DECLARE @ssh int
    EXEC @hr = sp_OACreate 'Chilkat.Ssh', @ssh OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @hostname nvarchar(4000)
    SELECT @hostname = 'ssh.example.com'
    DECLARE @port int
    SELECT @port = 22
    EXEC sp_OAMethod @ssh, 'Connect', @success OUT, @hostname, @port
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    --  Normally you would not hard-code the password in source.  You should instead obtain it
    --  from an interactive prompt, environment variable, or a secrets vault.
    DECLARE @password nvarchar(4000)
    SELECT @password = 'mySshPassword'

    EXEC sp_OAMethod @ssh, 'AuthenticatePw', @success OUT, 'mySshLogin', @password
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    DECLARE @channelNum int
    EXEC sp_OAMethod @ssh, 'OpenSessionChannel', @channelNum OUT
    IF @channelNum < 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    --  Start a shell WITHOUT requesting a PTY.  Without a PTY the shell sees it is connected to a
    --  raw data pipe and enters non-interactive mode: it suppresses the command prompt, does not
    --  echo typed commands back, and skips interactive login scripts.  The output is therefore
    --  clean and easily parseable -- but because no prompt is ever sent, code must not wait for
    --  one.  Instead, have each command print a predictable marker, or wait for EOF / channel close.
    EXEC sp_OAMethod @ssh, 'SendReqShell', @success OUT, @channelNum
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    --  IMPORTANT: Set a read timeout before receiving until a match.  ReadTimeoutMs defaults to 0,
    --  which means no limit -- without it, this call waits forever if the received data never
    --  contains a match.
    EXEC sp_OASetProperty @ssh, 'ReadTimeoutMs', 15000

    DECLARE @caseSensitive int
    SELECT @caseSensitive = 1

    --  ---- 1st command: change directory ----
    EXEC sp_OAMethod @ssh, 'ChannelSendString', @success OUT, @channelNum, 'cd /tmp; echo END_OF_CMD_1' + CHAR(10), 'utf-8'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    EXEC sp_OAMethod @ssh, 'ChannelReceiveUntilMatch', @success OUT, @channelNum, 'END_OF_CMD_1', 'utf-8', @caseSensitive
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    --  Retrieving the text also clears the receive buffer, which matters: if the next marker were
    --  left in the buffer, the following receive would match immediately.
    DECLARE @cmdOutput nvarchar(4000)
    EXEC sp_OAMethod @ssh, 'GetReceivedText', @cmdOutput OUT, @channelNum, 'utf-8'
    EXEC sp_OAGetProperty @ssh, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    PRINT @cmdOutput

    --  ---- 2nd command: directory listing ----
    EXEC sp_OAMethod @ssh, 'ChannelSendString', @success OUT, @channelNum, 'ls; echo END_OF_CMD_2' + CHAR(10), 'utf-8'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    EXEC sp_OAMethod @ssh, 'ChannelReceiveUntilMatch', @success OUT, @channelNum, 'END_OF_CMD_2', 'utf-8', @caseSensitive
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    EXEC sp_OAMethod @ssh, 'GetReceivedText', @cmdOutput OUT, @channelNum, 'utf-8'
    EXEC sp_OAGetProperty @ssh, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    PRINT @cmdOutput

    --  ---- 3rd command: long listing, then finish the session ----
    EXEC sp_OAMethod @ssh, 'ChannelSendString', @success OUT, @channelNum, 'ls -l' + CHAR(10), 'utf-8'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    --  No more input will be sent.
    EXEC sp_OAMethod @ssh, 'ChannelSendEof', @success OUT, @channelNum
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    EXEC sp_OAMethod @ssh, 'ChannelReceiveToClose', @success OUT, @channelNum
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    EXEC sp_OAMethod @ssh, 'GetReceivedText', @cmdOutput OUT, @channelNum, 'utf-8'
    EXEC sp_OAGetProperty @ssh, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 = 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    PRINT @cmdOutput

    EXEC sp_OAMethod @ssh, 'Disconnect', NULL

    EXEC @hr = sp_OADestroy @ssh


END
GO