Ideally I'd just remove the parameter to caddy.Context.Logger(), but
this would break most Caddy plugins.
Instead, I'm making it variadic and marking it as partially deprecated.
In the future, I might completely remove the parameter once most
plugins have updated.
This allows users to, for example, get upstreams from multiple SRV
endpoints in order (such as primary and secondary clusters).
Also, gofmt went to town on the comments, sigh
* reverseproxy: Begin refactor to enable dynamic upstreams
Streamed here: https://www.youtube.com/watch?v=hj7yzXb11jU
* Implement SRV and A/AAA upstream sources
Also get upstreams at every retry loop iteration instead of just once
before the loop. See #4442.
* Minor tweaks from review
* Limit size of upstreams caches
* Add doc notes deprecating LookupSRV
* Provision dynamic upstreams
Still WIP, preparing to preserve health checker functionality
* Rejigger health checks
Move active health check results into handler-specific Upstreams.
Improve documentation regarding health checks and upstreams.
* Deprecation notice
* Add Caddyfile support, use `caddy.Duration`
* Interface guards
* Implement custom resolvers, add resolvers to http transport Caddyfile
* SRV: fix Caddyfile `name` inline arg, remove proto condition
* Use pointer receiver
* Add debug logs
Co-authored-by: Francis Lavoie <lavofr@gmail.com>