Caddyfile: Add "resolvers" as a subdirective of "tls"

[francislavoie]

Currently, resolvers only exists as an option of issuer https://caddyserver.com/docs/caddyfile/directives/tls#issuers. If a user wants to configure resolvers, then they need to do it like this, to manually propagate the resolvers to all the relevant issuers:

tls {
	issuer zerossl {
		resolvers 8.8.8.8:53
		dns gandi {env.GANDI_APIKEY}
	}
	issuer acme {
		resolvers 8.8.8.8:53
		dns gandi {env.GANDI_APIKEY}
	}
}

Most tls options like email and dns get copied down to the default issuers, if no issuers are specified. A user on Discord wanted the same to be done for resolvers as well.

Basically, the ideal config would be this, to avoid repetition and specifying the issuers:

tls {
	dns gandi {env.GANDI_APIKEY}
	resolvers 8.8.8.8:53
}

[mholt]

Easy breezy.

[MagnuM2K]

Thanks!
This works like a charm.
Anyway to specify the order of issuer, though?

I had put ZeroSSL as primary (just because I could.. ;) ) and now with this change, it grabs a cert from LE.

[mholt]

@MagnuM2K It honors the order you specify in your config. To get more help, please ask on our forum: https://caddy.community - and fill out the template. Thanks!