Show LetsEncrypt certinfo on dietpi-banner for non-root users

[FrapiFrance]

Non-root users can't see LetsEncrypt valid end date because no access to /etc/letsencrypt/live/*
So LetsEncrypt shows "No certificate found".
This side script with sudo allows everybody to see Let's Encrypt cert status

[MichaIng]

Thanks, makes sense to handle non-root cases gracefully. However, always using sudo (even doubled, again within the script) and a dedicated script is high overhead. We should change it like that:

• Behave like before when user is root.
• Turn the dedicated script into a function within main script. It can be called via sudo bash -c "$(deflare -f function); function".

[FrapiFrance]

* Behave like before when user is root.
* Turn the dedicated script into a function within main script. It can be called via `sudo bash -c "$(deflare -f function); function"`.

Right, I will do that.

Thanks

[MichaIng]

I found a way to merge the sudo -n test with the actual sudo call: sudo errors are now muted, and instead the NOPASSWD info is shown. But since the file descriptor bindings within the sudo shell seem to be done earlier, it is possible to keep printing openssl errors (or any error within the sudo shell) in the banner, which I find important in case of other issues.

It is not perfect: If sudo or dash (the actual process, not the contained commands) fail for some other reason than missing NOPASSWD, you won't see their errors anymore and the NOPASSWD info is misleading. But those would then only be possible instead of corrupted files or configs, which should be recognised early elsewhere.