How to run git fetch over ssh in a windows subprocess

Question

I've got some code which needs to grab code from github periodically (on a Windows machine).

When I do pulls manually, I use GitBash, and I've got ssh keys running for the repos I check so everything is fine. However when I try to run the same actions in a python subprocess I don't have the ssh services which GitBash provides and I'm unable to authenticate to the repo.

How should I proceed from here. I can think of a couple of different options:

1. I could revert to using https:// fetches. This is problematic because the repos I'm fetching use 2-factor authentication and are going to be running unattended. Is there a way to access an https repo that has 2fa from a command line?

2. I've tried calling sh.exe with arguments that will fire off ssh-agent and then issuing my commands so that everything is running more or less the way it does in gitBash, but that doesn't seem to work:

   "C:\Program Files (x86)\Git\bin\sh.exe" -c "C:/Program\ Files\ \(x86\)/Git/bin/ssh-agent.exe; C:/Program\ Files\ \(x86\)/Git/bin/ssh.exe -t [email protected]"
   

   produces

   SSH_AUTH_SOCK=/tmp/ssh-SiVYsy3660/agent.3660; export SSH_AUTH_SOCK;
   SSH_AGENT_PID=8292; export SSH_AGENT_PID;
   echo Agent pid 8292;
   Could not create directory '/.ssh'.
   The authenticity of host 'github.com (192.30.252.129)' can't be established.
   RSA key fingerprint is XXXXXXXXXXX
   Are you sure you want to continue connecting (yes/no)? yes
   Failed to add the host to the list of known hosts (/.ssh/known_hosts).
   Permission denied (publickey).
   

3. Could I use an ssh module in python like paramiko to establish a connection? It looks to me like that's only for ssh'ing into a remote terminal. Is there a way to make it provide an ssh connection that git.exe can use?

So, I'd be grateful if anybody has done this before or has a better alternative

Answer 1

The git bash set the HOME environment variable, which allows git to find the ssh keys (in %HOME%/.ssh)

You need to make sure the python process has or define HOME to the same PATH.
As explained in "Python os.environ["HOME"] works on idle but not in a script", you need to set HOME to %USERPROFILE% (or, in python, to os.path.expanduser("~") ).

• theodox: That did it, thanks! Setting the HOME variable correctly got it running