resync: send a file to remote host, repeatedly

resync is a super-simple utility that opens an SSH connection to a remote host, watches a remote file for changes, and copies the file to the remote host when it notices a change. You could certainly implement this yourself with some sort of shell loop; I wrote this because I had to copy a binary to a remote system over and over again, where the SSH handshake would take more than a few seconds each time, and I got tired of waiting. This utility keeps the session open while watching the local file, so that handshaking only happens once.

tl;dr

$ resync local_file remote_host:/remote/path/to/file
INFO - connected to remote_host.
INFO - resyncing local_file => /remote/path/to/file
INFO - local_file => /remote/path/to/file in 1.21s (3.5 MB/s)
INFO - watching local file for changes
[...time passes, file changes...]
INFO - resyncing local_file => /remote/path/to/file
INFO - local_file => /remote/path/to/file in 0.73s (5.9 MB/s)

Installation

For now you have to use cargo to build and install it. When I have a few more pain points corrected, I will upload it to crates.io. Until then...

git clone https://github.com/Crosse/resync.git
cd resync
cargo install --path .

Issues

Just like Genie in Aladdin, this comes with some caveats and addendums. While it uses libssh under the hood, it doesn't parse your SSH config, so it won't know about any custom proxies or any other SSH configuration you might have. (This is sad and I'd love to fix it.) It also doesn't do any DNS resolution on the remote host, and for some reason libssh can't find non-FQDN names in your known_hosts file.

License

MIT. Feel free to fork, modify, and not give back, as long as the license stays intact. (I mean, I'd love it if you did upstream any changes, but you do you.) I made this for me, and any benefit others might derive from it is really tangential to its original purpose.