Conditionally switching HTTPS for different domains in nginx

server.rewrites

# Unfortunately, we are not able to set the server {} due to hosting limitations. 
# So we don't care that if is evil. We love if. Hooray for if!

# We want to redirect HTTP traffic to HTTPS, but only for two of our domains (the other domains still only use HTTP)

# set a var to 0 so when after a redirect, the existing connection is still used, 
# the flag is set back to 0 instead of remembering its previosly set value
set $http 0;

# give the var a random value (in this case 1) when the if statement is true
if ($scheme = http) {
        set $http 1;
}

# append another random value when the http_host matches to the domain 
# you want to enable https redirect for
if ($http_host = www.yourssldomain.nl) {
        set $http "${http}1"; 
}

if ($http_host = www.yourotherssldomain.nl) {
        set $http "${http}1";
}

# check the value whether both if statements are true and redirect to https version
if ($http = 11) {
        return 301 https://$http_host$request_uri;
}