NGINX SSL redirects too often - node.js

Question

I am struggling with NGINX and setting up my v-hosts. I'm trying to setup a vhost that redirects HTTP requests to HTTPS and then to my application (when it is 443)
My OS is Ubuntu 16.04 and I am using NGINX 1.10.3.
The nginx.conf looks like that (its mostly the default):
user www-data;
worker_processes auto;
pid /run/nginx.pid;
events {
worker_connections 768;
}
http {
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 65;
types_hash_max_size 2048;
include /etc/nginx/mime.types;
default_type application/octet-stream;
server_tokens off;
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
ssl_prefer_server_ciphers on;
access_log /var/log/nginx/access.log;
error_log /var/log/nginx/error.log;
gzip on;
gzip_disable "msie6";
include /etc/nginx/conf.d/*.conf;
include /etc/nginx/sites-enabled/*;
}
My ServerBlocks / VHosts look like that:
server {
listen 443 ssl;
server_name xxx.com;
# Prevent MITM
add_header Strict-Transport-Security "max-age=31536000";
ssl_certificate "/etc/nginx/ssl/xxx.com.pem";
ssl_certificate_key "/etc/nginx/ssl/xxx.com.key";
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
ssl_ciphers HIGH:!aNULL:!MD5;
location / {
proxy_pass http://localhost:2237;
}
}
server {
listen 80;
server_name xxx.com;
return 301 https://$server_name$request_uri;
}
Now the problem is, that either if I am using HTTP or HTTPS it tries to redirect me to HTTPS so I am stucked in an endless Loop of redirects.
I have absolutely no idea where my mistake is.
Every VHost is in a single File. The Application on Port 2237 is a nodeJS Express Server. I am also using Cloudflare (I got my SSL Certificate from them)
Edit:
Output from curl -I is:
$ curl -I https://example.com
HTTP/1.1 301 Moved Permanently
Date: Fri, 06 Oct 2017 19:42:19 GMT
Content-Type: text/html
Connection: keep-alive
Set-Cookie: __cfduid=d827df762e20a4e321b92b34bd15546621507318939; expires=Sat, 06-Oct-18 19:42:19 GMT; path=/; domain=.example.com; HttpOnly
Location: https://example.com/
Server: cloudflare-nginx
CF-RAY: 3a9b1a6a4e4564d5-FRA

Answer 1

You need to use below config
server {
listen 80;
server_name example.com;
add_header Strict-Transport-Security "max-age=31536000";
location / {
proxy_pass http://localhost:2237;
proxy_redirect http://localhost:2237/ https://$host/;
}
}
Your are using cloudflare SSL and terminating SSL at cloudflare. So you should just be listening on port 80. Your earlier config was redirecting port 80 back to HTTPS and sending the request to Cloudflare which then send to your nginx port 80 and hence creating infinite loop