Lets Encrypt app: Support "httpreq" provider

[LordMike]

I've run the LE provider for a while with an API key to cloudflare so it could do the DNS-01 challenge there. The unfortunate downside is of course that now my HA instances has an API key that controls my entire DNS zone. CF back then only offered "global API keys", which were horrible, but now at least they have somewhat scoped API keys that can only do f.ex. zone edits. Unfortunately their Zone edits still apply to a whole zone.

To combat this, I'm experimenting with dns01proxy, which is a LAN-local HTTP server that proxies DNS edits. I can set up acme.sh with this f.ex., and also lego - but unfortunately the LE App does not have the httpreq provider exposed via configuration. Its my impression that it "just" needs to expose the proper config params, and then httpreq can be used.

Resources:

• lego's httpreq
• dns01proxy lego example

As a sidenote. The lego site lists 194 providers (some seem dubious, so likely not all 194 are valid), while the LE app only offers 44 of those providers as config options. Was there a reason why not every provider was just mapped over? I've seen the setup script and it does seem to hold per-provider mappings of config input to lego env vars.. so there is that.

[LordMike]

I made a PR for this. home-assistant/addons#4545