Git credentials v23

You can clone Git repositories that require authentication. If you're installing Postgres from source or using install_from_source to compile and install extensions, and the source repositories require authentication, you can use SSH key-based authentication or HTTPS username/password based authentication to access them with TPA.

You have two options to authenticate without writing the credentials to disk on the target instance:

  • For an ssh:// repository, you can add an SSH key to your local SSH agent. Agent forwarding is enabled by default if you use --install-from-source (forward_ssh_agent: yes in config.yml).

  • For an https:// repository, you can export TPA_GIT_CREDENTIALS=username:token in your environment before running tpaexec deploy.

Note

Docker containers on macOS can't use ssh:// URLs because SSH access from the host to containers doesn't work. https:// repository URLs will work fine.

SSH key authentication

If you're cloning an SSH repository and have an SSH key pair (id_example and id_example.pub), use SSH agent forwarding to authenticate on the target instances:

  • You need to run ssh-agent locally. If your desktop environment doesn't already set this up for you (as most do: pgrep ssh-agent to check if it's running), run ssh-agent bash to temporarily start a new shell with the agent enabled. Then run tpaexec deploy from that shell.

  • Add the required key(s) to the agent with ssh-add /path/to/id_example (the private key file).

  • Enable SSH agent forwarding by setting forward_ssh_agent: yes at the top level in config.yml before tpaexec provision. (This is done by default if you use --install-from-source.)

During deployment, any keys you add to your agent are made available for authentication to remote servers through the forwarded agent connection.

Use SSH agent forwarding with caution, preferably with a disposable key pair generated specifically for this purpose. Users with the privileges to access the agent's Unix domain socket on the target server can co-opt the agent into impersonating you while authenticating to other servers.

HTTPS username/password authentication

If you're cloning an HTTPS repository with a username and authentication token or password, just export TPA_GIT_CREDENTIALS=username:token in your environment before tpaexec deploy. During deployment, these credentials are made available to any git clone or git pull tasks (only). They aren't written to disk on the target instances.