Redirecting base domain to HTTPS, and sub-domains to HTTP - apache

Question

I've been using Apache for a project, and have now decided to convert over to nginx for performance reasons as the project has grown quite a bit.
For this project, we serve our base domain and www sub-domain over HTTPS, but need to serve all other sub-domains over HTTP.
In Apache, I was able to accomplish this with the RewriteEngine doing the following:
RewriteEngine On
#Redirect domain and www to HTTPS
RewriteCond %{HTTPS} off
RewriteCond %{HTTP_HOST} =mydomain.com [OR]
RewriteCond %{HTTP_HOST} =www.mydomain.com
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
#Redirect wildcard subdomains to HTTP
RewriteCond %{HTTPS} on
RewriteCond %{HTTP_HOST} ^(.+)\.mydomain\.com [NC]
RewriteCond %{HTTP_HOST} !=www.mydomain.com
RewriteRule (.*) http://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
I have my website about half setup with nginx, and this portion of the configuration has stumped me. How do I go about converting this to work with nginx?

Answer 1

I divided the answer in 4 virtual host. The first two solve the http to https redirect among the main domains. And the second part catches the subdomains and redirects from https to http:
# FIRST PART ---------------
# from http to https on main domains
server {
listen 80;
server_name domain www.domain;
location / {
return 301 https://$host$request_uri;
}
}
server {
listen 443 ssl;
server_name domain www.domain;
# blah, blah, https and virtualhost configuration
}
# SECOND PART ---------------
# from https to http and others subdomains
server {
listen 443 ssl;
server_name *.domain;
# blah, blah, https configuration
location / {
return 301 http://$host$request_uri
}
}
server {
listen 80;
server *.domain;
# virtual with http configuration
}