python socket file transfer

Question

I\'m trying to write transfer files or chunks of data over a socket. I feel as if I\'m reinventing the wheel, but my searches for a simple solution have failed (everything I

Answer 1

rsync is the standard way to sync files between two computers. You could write it in Python like this http://code.activestate.com/recipes/577518-rsync-algorithm/ or you could wrap the C library like this http://freshmeat.net/projects/pysync/ with some tweaks like replacing MD4 with MD5.

Or, if you want to do this at the socket level, you really should be using asynchat with asyncore. Here is an FTP server written with asynchat http://pyftpdlib.googlecode.com/svn-history/r20/trunk/pyftpdlib/FTPServer.py but you should start by reading http://www.doughellmann.com/PyMOTW/asynchat/ Pay attention to the part about Message Terminators point 2. A lot of network protocols do odd stuff like this, i.e. sometimes they send and receive full line commands and responses, and sometimes they send and receive chunks of arbitrary data preceded by the count of how many bytes are in the chunk. You can handle this much more easily with asynchat, and your program will scale much better too.