sftpsyncer

sftpsyncer

Synchronise files piecemeal back and forth between a local cache and a remote SFTP server.

Use case

You have a client that sometimes needs to syncronise files to and from an SFTP server.

• open() a file whether it's remote or local.
  • If the file is available locally, use the local copy.
  • If the local file doesn't exist, download it and then use the local copy.
• add() files to an upload package, then push() to upload all locally queued files.

This model is simplistic, and will clobber any changes at the other end if a file with the same name exists. If you want to avoid that, you may be better off using Git or the like.

How to use::

import sftpsyncer
from sftpsyncer import syncagent

sagent = syncagent(hostname="remote_sagenth.example.com", host_port="1222",
                username="theuser", key_path="/home/theuser/.sagenth/key",
                local_root="/tmp/cache", remote_root="/upload_target")

# upload local files

sagent.upload_queue.add("myfile.txt")
sagent.upload_queue.add("docs/readme.txt")

sagent.push()  # upload whether or not remote files exist

# auto-get remote files, reading from cache when available

fh1 = sagent.open("myfile.txt")  # file is already local, return local fh
fh2 = sagent.open("remote.txt")  # file is not local, transfer to local cache, return local fh

# exceptions

try:
    fh3 = sagent.open("not_anywhere.txt")
except sftpsyncer.exceptions.FileNotFound as e:
    print "File does not exist on local or remote"

try:
    fh5 = sagent.open("ssh_server_unavailable.txt")
except sftpsyncer.exceptions.ConnectionError as e:
    print "Remote SFTP service appears to be unavailable"