Advanced Python FTP - can I control how ftplib talks to a server?

Question

I need to send a very specific (non-standard) string to an FTP server:

dir "SYS:\IC.ICAMA."

The case is critical, as are the style of quotes and their content.

Unfortunately, ftplib.dir() seems to use the 'LIST' command rather than 'dir' (and it uses the wrong case for this application).

The FTP server is actually a telephone switch and it's a very non-standard implementation.

I tried using ftplib.sendcmd(), but it also sends 'pasv' as part of the command sequence.

Is there an easy way of issuing specific commands to an FTP server?

Answer 1

Try the following. It is a modification of the original FTP.dir command which uses "dir" instead of "LIST". It gives a "DIR not understood" error with the ftp server I tested it on, but it does send the command you're after. (You will want to remove the print command I used to check that.)

import ftplib

class FTP(ftplib.FTP):

    def shim_dir(self, *args):
        '''List a directory in long form.
        By default list current directory to stdout.
        Optional last argument is callback function; all
        non-empty arguments before it are concatenated to the
        LIST command.  (This *should* only be used for a pathname.)'''
        cmd = 'dir'
        func = None
        if args[-1:] and type(args[-1]) != type(''):
            args, func = args[:-1], args[-1]
        for arg in args:
            if arg:
                cmd = cmd + (' ' + arg)
        print cmd
        self.retrlines(cmd, func)

if __name__ == '__main__':
    f = FTP('ftp.ncbi.nih.gov')
    f.login()
    f.shim_dir('"blast"')