I saw someone say to establish a connection between GVM and remote OSPD through SSH socket. Where should I find a similar document? Are there any other communication methods available?
Yes, this is done through gvm-cli which can listen on local Unix socket, TLS, and SSH to communicate with gvmd using GMP and OSP protocols. It can be installed via gvm-tools. I suggest complete review of the GVM docs. gvm-tools comes with some pre-built Python scripts, and ‘python-gvm’ can be used to build your own scripts.