I want create a REST API using nodejs and with expressjs, i want to deploy this on my VPS server, i've and haproxy on front of this VPS.
My question how to secure this with HTTPS protocol? I mean I need to buy a https certificate or I can use on self assign, cause that is only for secure the API routes. I never use HTTPS on my server before, I how if i need secure my website with https i need a public certificate however for API I think that is no need right?
Also I down know you to secure this on haproxy or on client side.
thanks in advance