The Query Stage Plugins API manages custom query stages developed using the Query Stage SDK.
The Query Stage SDK is not typically used by Managed Fusion. If you require a custom stage, it is recommended that you contact your Lucidworks representative for assistance.
Custom-made query stages are developed using the Query Stage SDK, which saves them as plugins. A plugin is a ZIP file that contains one or more query stage implementations. The ZIP file contains JAR files for stage definitions and additional dependencies. It also contains a manifest file that holds the metadata Managed Fusion uses to run the plugin. To learn more, see Example Query Stage Plugin. Example: upload a custom plugin stage Managed Fusion uses a cURL command with a PUT method for both installing and updating a plugin stage. Once all necessary information is entered or modified and saved as a ZIP file, use the following command to send the plugin stage to Managed Fusion. Change the value of sample-plugin-stage-0.0.1.zip to match the name of your ZIP file. 
curl -u USERNAME:PASSWORD -X PUT -H "Content-Type:application/zip" --data-binary @sample-plugin-stage-0.0.1.zip https://EXAMPLE_COMPANY.b.lucidworks.cloud/api/query-stage-plugins
You can use a GET request to the query-stage-plugins endpoint to list the installed query stage plugins. Here the USERNAME:PASSWORD is base64 encoded. The response returns a list of query stage plugin IDs, which are needed if you want to use the API to delete a plugin. 
curl --request GET \
  --url https://EXAMPLE_COMPANY.b.lucidworks.cloud/api/query-stage-plugins \
  --header 'Accept: application/json' \
  --header 'Authorization: Basic USERNAME:PASSWORD
To delete a query stage plugin, you will need to know the plugin ID that you want to delete. 
curl --request DELETE \
  --url https://EXAMPLE_COMPANY.b.lucidworks.cloud/api/query-stage-plugins/PLUGIN_ID \
  --header 'Authorization: Basic USERNAME:PASSWORD