Boost ASIO SSL server, use different certificate depending on SNI

Question

I'm currently writing a small HTTP server, and I would like to implement SSL. The goal is to be able to do load multiple PEM files in boost so it can do a correct SSL handshake with a client depending on the SNI sent in TLS.

However I don't see how I can load multiple PEM files in boost and also how I can tell it to use one cert or another depending on this SNI.

For example I load the cert with:

context.use_certificate_file("cert.pem");
m_context.use_private_key_file("server.pem", 
boost::asio::ssl::context::pem);