SQL Server

Download an FTP File to a Stream

Demonstrates the Chilkat Ftp2.GetFileToStream method, which downloads a remote file and writes its bytes to a Stream. The first argument is the remote file path and the second is the Stream, which must have a destination sink configured beforehand.

Note: The local paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: Streaming to a Stream object decouples the download from where the bytes ultimately go — a file (as here, via SinkFile), or a pipe feeding another component such as a decompressor or a hashing routine — and processes the data as it arrives rather than buffering the whole file. That keeps memory flat for large downloads and lets you chain the transfer into a processing pipeline.

Chilkat SQL Server Downloads

Download Chilkat for SQL Server

SQL Server

--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

    --  Demonstrates the Ftp2.GetFileToStream method, which downloads a remote file and writes its
    --  bytes to a Stream.  The 1st argument is the remote file path and the 2nd is the Stream.

    DECLARE @ftp int
    EXEC @hr = sp_OACreate 'Chilkat.Ftp2', @ftp OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    EXEC sp_OASetProperty @ftp, 'Hostname', 'ftp.example.com'
    EXEC sp_OASetProperty @ftp, 'Username', 'myFtpLogin'

    --  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.
    EXEC sp_OASetProperty @ftp, 'Password', 'myPassword'

    EXEC sp_OAMethod @ftp, 'Connect', @success OUT
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ftp, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ftp
        RETURN
      END

    --  Configure the stream's destination sink before downloading.  Here the stream writes to a
    --  local file.
    DECLARE @fileStream int
    EXEC @hr = sp_OACreate 'Chilkat.Stream', @fileStream OUT

    EXEC sp_OASetProperty @fileStream, 'SinkFile', 'qa_output/report.pdf'

    EXEC sp_OAMethod @ftp, 'GetFileToStream', @success OUT, 'public_html/report.pdf', @fileStream
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ftp, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ftp
        EXEC @hr = sp_OADestroy @fileStream
        RETURN
      END

    PRINT 'Downloaded to stream.'

    EXEC sp_OAMethod @ftp, 'Disconnect', @success OUT
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @ftp, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ftp
        EXEC @hr = sp_OADestroy @fileStream
        RETURN
      END

    EXEC @hr = sp_OADestroy @ftp
    EXEC @hr = sp_OADestroy @fileStream


END
GO