Updated dnsapi2 (markdown)

dnsapi2.md

@@ -97,6 +97,7 @@
 - [173. Use ZoneEdit DNS API](#dns_zoneedit)
 - [174. Use Anikeen Cloud DNS API](#dns_anikeen)
 - [175. Use mijn.host DNS API](#dns_mijnhost)
+- [176. Use OpenProvider (REST) DNS API](#dns_openprovider_rest)
 - [Use custom API](#dns_myapi)
 - [Use lexicon DNS API](#dns_lexicon)
 
@@ -2427,6 +2428,33 @@ To issue a cert:
 
 Report any bugs or issues [here](https://github.com/acmesh-official/acme.sh/issues/6177)
 
+<a name="dns_openprovider_rest"/>
+
+## 176. Use OpenProvider (REST) DNS API *(merge request pending)*
+
+This script uses DNS API for [OpenProvider](https://www.openprovider.com) domain and dns service and is based on their newer REST [API documentation](https://docs.openprovider.com/doc/all). Now allowing usage of a single request validation entry for the DNS API script without the need to do a full DNS zone overlay everytime like in the older XML specifications.
+
+Before first execution define the following in sh (or bash):
+```sh
+export OPENPROVIDER_REST_USERNAME="username"
+export OPENPROVIDER_REST_PASSWORD="password"
+``` 
+
+The API authentication is based on the [OpenProvider control panel](https://cp.openprovider.eu) credentials;
+* username: API/account username, same as OpenProvider control panel username
+* password: API/account password, same as OpenProvider control panel username
+
+Both `OPENPROVIDER_REST_USERNAME` and `OPENPROVIDER_REST_PASSWORD` will be saved in `~/.acme.sh/account.conf` and will be reused when needed.
+
+If there are multiple control panel contacts (like admin/tech/billing) under a reseller account, decide which account/contact you want to use for API connection/integration and use its username and password. You could create a dedicated account for the DNS API scripting to be executed. For more information please use the OpenProvider article [Getting-started-with-Openprovider-API](https://support.openprovider.eu/hc/en-us/articles/360025683173-Getting-started-with-Openprovider-API)
+
+To issue a cert:
+```sh
+./acme.sh --issue --dns dns_openprovider_rest -d example.com -d *.example.com
+```
+
+Report any bugs or issues [here](https://github.com/acmesh-official/acme.sh/issues/6122)
+
 ## Use custom API
 
 If your API is not supported yet, you can write your own DNS API.