SSL for domain, including subdomains - redirect

Question

I have a domain, example.com. From that, I have these:
blog.example.com
api.example.com
books.example.com
I have acquired SSL cert for root domain and its subdomains.
And I want the redirections to be like so:
http://example.com => https://example.com
http://blog.example.com => https://blog.example.com
http://books.example.com => https://books.example.com
This is my example.com nginx conf
server {
listen 443 ssl default_server;
root /home/django/khophi;
index index.html index.htm;
server_name example.com;
include /etc/nginx/globalssl.conf; //ssl config
}
server {
listen 80 default_server;
server_name example.com;
return 301 https://$host$request_uri;
}
nginx conf for blog.example.com
server {
listen 443 ssl; // now listens for https
root /var/www/html/blog;
index index.php index.html index.htm;
server_name blog.example.com;
#include /etc/nginx/globalssl.conf;
location / {
try_files $uri $uri/ /index.php?q=$uri&$args;
}
// error pages
location ~ \.php$ {
//php specific things
}
}
server {
listen 80;
server_name blog.example.com;
return 301 https://blog.example.com$request_uri;
}
books.example.com follows similar structure as blog.example.com conf
What happens With the above setup?
Visit to http://example.com redirects to https://example.com (just as I want
Visit to http://blog.example.com redirects to https://blog.example.com BUT, shows page of https://example.com
In my case, I want:
example.com to remain as default_server
http://example.com to redirect to https://example.com
ALL http:// requested subdomains to redirect to their respective https:// versions
if a subdomain is requested which doesn't exist, it should redirect to default_server (https://example.com)

Answer 1

Instead of using return, i use rewrite instead on the redirection server block on the main domain and its subdomains, like so:
// blog.example.com
server {
listen 80;
server_name blog.example.com;
rewrite ^ https://$server_name$request_uri? permanent;
}
// example.com
server {
listen 80 default_server;
server_name example.com;
rewrite ^ https://$server_name$request_uri? permanent;
}
This link helped