Traversing FTP listing

Question

I am trying to to get all directories\' name from an FTP server and store them in hierarchical order in a multidimensional list or dict

So for example, a server that

Answer 1

Here is a naive and slow implementation. It is slow because it tries to CWD to each directory entry to determine if it is a directory or a file, but this works. One could optimize it by parsing LIST command output, but this is strongly server-implementation dependent.

import ftplib

def traverse(ftp, depth=0):
    """
    return a recursive listing of an ftp server contents (starting
    from the current directory)

    listing is returned as a recursive dictionary, where each key
    contains a contents of the subdirectory or None if it corresponds
    to a file.

    @param ftp: ftplib.FTP object
    """
    if depth > 10:
        return ['depth > 10']
    level = {}
    for entry in (path for path in ftp.nlst() if path not in ('.', '..')):
        try:
            ftp.cwd(entry)
            level[entry] = traverse(ftp, depth+1)
            ftp.cwd('..')
        except ftplib.error_perm:
            level[entry] = None
    return level

def main():
    ftp = ftplib.FTP("localhost")
    ftp.connect()
    ftp.login()
    ftp.set_pasv(True)

    print traverse(ftp)

if __name__ == '__main__':
    main()