Nginx:Security Header Setting

nano /etc/nginx/nginx.conf

user www-data;
worker_processes auto;
pid /run/nginx.pid;
include /etc/nginx/modules-enabled/*.conf;

events {
	worker_connections 768;
	# multi_accept on;
}

http {

	##
	# Basic Settings
	##
	sendfile on;
	tcp_nopush on;
	tcp_nodelay on;
	keepalive_timeout 65;
	types_hash_max_size 2048;
	client_max_body_size 2048M;
        proxy_headers_hash_max_size 1024;
        proxy_headers_hash_bucket_size 128;
        add_header Cache-Control "public, max-age=15778463";
        add_header Content-Security-Policy origin;
        add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
        add_header X-Content-Type-Options nosniff;
        add_header X-Frame-Options "SAMEORIGIN";
        add_header X-XSS-Protection "1; mode=block";
        add_header X-Robots-Tag none;
        add_header X-Download-Options noopen;
        add_header X-Permitted-Cross-Domain-Policies none;
        add_header Referrer-Policy no-referrer always;
	include /etc/nginx/mime.types;
	default_type application/octet-stream;
        server_tokens off;
	##
	# SSL Settings
	##

	ssl_protocols TLSv1 TLSv1.1 TLSv1.2; # Dropping SSLv3, ref: POODLE
	ssl_prefer_server_ciphers on;

	##
	# Logging Settings
	##

	access_log /var/log/nginx/access.log;
	error_log /var/log/nginx/error.log;

	##
	# Gzip Settings
	##

	gzip on;

	 gzip_vary on;
	 gzip_proxied any;
	 gzip_comp_level 6;
	 gzip_buffers 16 8k;
	 gzip_http_version 1.1;
	 gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;

	##
	# Virtual Host Configs
	##

	include /etc/nginx/conf.d/*.conf;
	include /etc/nginx/sites-enabled/*;
        #brotli on;
        #brotli_comp_level 6;
        #brotli_static on;
        #brotli_types text/plain text/css application/javascript application/x-javascript text/xml application/xml application/xml+rss text/javascript image/x-icon image/vnd.microsoft.icon image/bmp image/svg+xml;
lua_shared_dict prometheus_metrics 10M;
lua_package_path "/root/nginx-lua-prometheus/prometheus.lua";
init_by_lua '
  prometheus = require("prometheus").init("prometheus_metrics")
  metric_requests = prometheus:counter(
    "nginx_http_requests_total", "Number of HTTP requests", {"host", "status"})
  metric_latency = prometheus:histogram(
    "nginx_http_request_duration_seconds", "HTTP request latency", {"host"})
  metric_connections = prometheus:gauge(
    "nginx_http_connections", "Number of HTTP connections", {"state"})
';
log_by_lua '
  metric_requests:inc(1, {ngx.var.server_name, ngx.var.status})
  metric_latency:observe(tonumber(ngx.var.request_time), {ngx.var.server_name})
';
}