use current work dir or temp dir to avoid ConfigDir error

[zuoRambo]

unable to get current user home directory: os/user lookup failed; $HOME is empty

I build my application on instance A and run it on instance B.
The app run as user root and the env variable $HOME is /root.
But i got the follow error.

Maybe we should use temp dir

func ConfigDir() (string, error) {
	if runtime.GOOS == "windows" {
		return filepath.Join(os.Getenv("APPDATA"), "gops"), nil
	}
	homeDir := guessUnixHomeDir()
	if homeDir == "" {
                // os.TempDir() or filepath.Abs(filepath.Dir(os.Args[0]))
		return "", errors.New("unable to get current user home directory: os/user lookup failed; $HOME is empty")
	}
	return filepath.Join(homeDir, ".config", "gops"), nil
}

[zuoRambo]

In production environment, the process's user is www and is nologin, In this case, the $HOME is not available.

[rakyll]

Can we just make the ConfigDir configurable via an env? Current directory is not the most optimal solution either. You don't want to cd into a specific directory to be able to run gops.

/cc @odeke-em

[odeke-em]

I totally agree with what @rakyll said, we can either check if it is configured first, then fallback to $HOME.

[zuoRambo]

Thank you @odeke-em for the help and @rakyll for the reviews!