add_dns_provider.md

Adding provider support

CloudDNS as an example

1. Fork this repo, modify autocert.go

   var providersGenMap = map[string]ProviderGenerator{
     "cloudflare": providerGenerator(cloudflare.NewDefaultConfig, cloudflare.NewDNSProviderConfig),
     // add here, i.e.
     "clouddns": providerGenerator(clouddns.NewDefaultConfig, clouddns.NewDNSProviderConfig),
   }

2. Go to https://go-acme.github.io/lego/dns/clouddns and check for required config

3. Build go-proxy with make build

4. Set required config in config.yml autocert -> options section

   # From https://go-acme.github.io/lego/dns/clouddns/
   CLOUDDNS_CLIENT_ID=bLsdFAks23429841238feb177a572aX \
   [email protected] \
   CLOUDDNS_PASSWORD=b9841238feb177a84330f \
   lego --email [email protected] --dns clouddns --domains my.example.org run

   Should turn into:

   autocert:
     ...
     options:
       client_id: bLsdFAks23429841238feb177a572aX
       email: [email protected]
       password: b9841238feb177a84330f

5. Run with GOPROXY_NO_SCHEMA_VALIDATION=1 and test if it works

6. Commit and create pull request