URL / IP Canonicalization - NGINX or Nodejs?

I want to use URL / IP Canonicalization to force wwww subdomain. So:

example.com should be forced to www.example.com to prevent duplicate content.

I am confused as to what technology to use for this. I'm familiar with Node.js, but I'm not sure if I should configure this in NGINX instead. I'm using a Dockerfile to containerize my app.

• How would my Dockerfile that look like for the NGINX approach?
• What are best practices and what are pros/cons between Node.js and NGINX?

via Nicky