Drops the cached answers of a custom API with enableCaching. resetCacheOnModificationOf in its settings does it on its own when a table it names is written ; this API is for the other cases.
Method
POST
URL
/api/system-api/admin/reset-redis-cache-custom-apis : admin is the user path of your account
Over HTTP, a system API answers only once its settings open it : TOKEN_ACCESS (the token of an API user whose group grants this system API) or IS_PUBLIC. Without settings it is NO_ACCESS : only your code (g.sys) and the admin panel reach it.
The settings can also keep the answer in the cache, or ask for the token of a person (authProviders). Pre and post hooks run around it, as around any API.
It takes the request headers and answers the envelope. 401 : no valid token, or the API is NO_ACCESS. 403 : no group grants it. 400 : the body is wrong, and the message names the key.