[Twisted-Python] FTP LIST

[Jean-Paul Calderone]

On Sun, 28 Dec 2008 11:52:56 +0000, Simply for IT <simply4it at gmail.com> wrote:
>Hi Everyone,
>
>I just have started to study twistedmatrix in my spare time couple of weeks
>ago. I am satisfied with the books, but as they are very terse, and they are
>not really FTP related, I could not figure out how the FTP is working.
>
>I would like to be able to filter/modify the LIST(ing) process. Eg after
>list(ing) the result should not list any .py files even if they are there.

>I have tried to look after IFTPShell, but no success sofar. Here is a code
>snipplet from the "official" testcases - or even from twisted.ftp)
>

IFTPShell is the way you control the behavior of the FTP server.  To exclude
certain results from a directory listing, you would implement the `list´
method so that it has the necessary logic for performing that exclusion.

>    def requestAvatar(self, avatarId, mind, *interfaces):
>         for iface in interfaces:
>            if iface is ftp.IFTPShell:
>                avatar = ftp.FTPShell(filepath.
>FilePath(self.root))
>                return ftp.IFTPShell, avatar, getattr(avatar, 'logout',
>lambda: None)
>
>Could anybody give me any advice, where to start, please?

You found an implementation of a realm which supports IFTPShell.  If you
aren't familiar with realms, read the cred documentation:

  http://twistedmatrix.com/projects/core/documentation/howto/cred.html

The realm is important but pretty simple.  The avatar, the IFTPShell
implementation, is what really controls the behavior you're interested
in.

Jean-Paul