How to get client certificates


I’m trying to develop a kong plugin to deal with client certificates. What interface should I use to get it?

I found kong.client.tls and tried to use get_full_client_certificate_chain but didn’t work (received nil nil).

Searching for similar questions here I found this topic where @James_Callahan recommended kong.resty.getssl but I’m not sure if this feature still available nor how to use it.