+* `invalidation`: options for remove media from cache after delete object:
+ * `enabled`: Enables purge cache
+ * `provider`: Which one of the [purge cache strategy](#purge-cache-strategy) to use.
+
+### Purge cache strategy
+
+#### Pleroma.Web.MediaProxy.Invalidation.Script
+
+This strategy allow perform external bash script to purge cache.
+Urls of attachments pass to script as arguments.
+
+* `script_path`: path to external script.
+
+Example:
+```elixir
+config :pleroma, Pleroma.Web.MediaProxy.Invalidation.Script,
+ script_path: "./installation/nginx-cache-purge.example"
+```
+
+#### Pleroma.Web.MediaProxy.Invalidation.Http
+
+This strategy allow perform custom http request to purge cache.
+
+* `method`: http method. default is `purge`
+* `headers`: http headers. default is empty
+* `options`: request options. default is empty
+
+Example:
+```elixir
+config :pleroma, Pleroma.Web.MediaProxy.Invalidation.Http,
+ method: :purge,
+ headers: [],
+ options: []
+```