I am working on a web application which requires pulling information from an X509 Client Certificate (DOD CAC / Smart Card) Header. Of interest is the Name and ID number, to be used in javascript for auto-populating fields.
The stack I am working with is a docker containerized static HTML/CSS/Javascript project running on an NGINX server.
I am new to server configuration, but I generally understand that querying for a client certificate is handled at the NGINX server configuration level, but my question is how would I ingest that information into the web app for use?