nginx.conf

events {
  worker_connections  1024;
}

http {
    map $http_x_forwarded_for $client_ip {
    # Default to $remote_addr if X-Forwarded-For is empty
    "" $remote_addr;
    # Extract the second to last IP
    ~^(?:[^,]+,)*([^,]+),[^,]+$ $1;
    # Use the only IP if there's just one
    ~^[^,]+$ $1;
    }
    limit_req_zone $client_ip zone=addr_limit:10m rate=10r/s;
    limit_req_status 429;
    # Add headers for rate limiting
    add_header X-RateLimit-Limit 10 always;
    add_header X-RateLimit-Burst 20 always;
    add_header X-RateLimit-Delay 5 always;
    server_tokens off;
    server {

        # Use the mapped $client_ip
        set_real_ip_from 10.0.0.0/8;
        real_ip_header X-Forwarded-For;
        real_ip_recursive on;

        listen 8080;
        server_name default_server;
        limit_req zone=addr_limit burst=20 delay=5;


        proxy_connect_timeout       600;
        proxy_send_timeout          600;
        proxy_read_timeout          600;
        send_timeout                600;

        client_max_body_size 50M;


        # Compression

         # Enable Gzip compressed.
         gzip on;

        # Enable compression both for HTTP/1.0 and HTTP/1.1.
        gzip_http_version  1.1;

        # Compression level (1-9).
        # 5 is a perfect compromise between size and cpu usage, offering about
        # 75% reduction for most ascii files (almost identical to level 9).
        gzip_comp_level    5;

        # Don't compress anything that's already small and unlikely to shrink much
        # if at all (the default is 20 bytes, which is bad as that usually leads to
        # larger files after gzipping).
        gzip_min_length    256;

        # Compress data even for clients that are connecting to us via proxies,
        # identified by the "Via" header (required for CloudFront).
        gzip_proxied       any;

        # Tell proxies to cache both the gzipped and regular version of a resource
        # whenever the client's Accept-Encoding capabilities header varies;
        # Avoids the issue where a non-gzip capable client (which is extremely rare
        # today) would display gibberish if their proxy gave them the gzipped version.
        gzip_vary          on;

        # Compress all output labeled with one of the following MIME-types.
        gzip_types
          application/javascript
          application/json
          application/x-font-ttf
          application/x-web-app-manifest+json
          application/xhtml+xml
          application/xml
          font/opentype
          image/svg+xml
          image/x-icon
          text/css
          text/plain
          text/x-component;

# Routes that have both frontend and backend implementation, dependent on requested content type

# The problem is cors call for server. Because it has accept html, would it be sent to frontend server, which does not implement cors
# as a work-around, we implement cors here in nginx for both cases

        location ~* /dataset-catalogs {
            proxy_pass http://dataset-catalog-gui:8080;
        }

        location ~* /catalogs {

            if ($request_method = 'OPTIONS') {
                add_header 'Access-Control-Allow-Origin' '*';
                add_header 'Access-Control-Allow-Methods' 'GET, POST, PATCH, DELETE, OPTIONS';
                #
                # Custom headers and headers various browsers *should* be OK with but aren't
                #
                add_header 'Access-Control-Allow-Headers' 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range,Authorization';
                #
                # Tell client that this pre-flight info is valid for 20 days
                #
                add_header 'Access-Control-Max-Age' 1728000;
                add_header 'Content-Type' 'text/plain; charset=utf-8';
                add_header 'Content-Length' 0;
                return 204;
            }

            if ($http_accept ~* "application/json") {
                  proxy_pass http://dataset-catalog:8080;
            }
            if ($http_accept ~* "text/turtle") {
                  proxy_pass http://dataset-catalog:8080;
            }

            proxy_pass http://new-dataset-catalog-gui:8080;
        }

        location /search {
            proxy_pass http://dataset-catalog:8080;
        }

        location /terms-and-conditions {
            proxy_pass http://terms-and-conditions-gui:8080;
        }

        location / {
            proxy_pass http://registration-portal:8080;
        }

    }
}