Updated Readme for ECS standard support docs

README.md

@@ -168,4 +168,17 @@ ip_api_proxy_successful_queries_total 0
 ip_api_proxy_successful_single_queries_total 0
 ```
 
+## Elastic Common Schema (ECS) Support
+
+Support for outputting IP-API results in the [ECS Standard](https://www.elastic.co/guide/en/ecs/current/ecs-geo.html) has been added. In order to get results in this format, when making queries against the API use ecs=false in the HTTP request:
+
+ex:
+```
+http://localhost:8080/batch?ecs=true
+```
+
+This will return an output that matches the [ECS Standard](https://www.elastic.co/guide/en/ecs/current/ecs-geo.html)
+
+Note: There are additional fields returned by IP-API, that are not listed under [ECS Standard](https://www.elastic.co/guide/en/ecs/current/ecs-geo.html), if you want to index these fields, please make sure you're index template is designed to handle them.
+
 If you have ideas for other metrics which you feel would be useful, please let me know.