proxy_cache_path /data/nginx/cache levels=1:2 keys_zone=skynet:10m max_size=10g use_temp_path=off;
limit_req_zone $binary_remote_addr zone=stats_by_ip:10m rate=10r/m;
limit_conn_zone $binary_remote_addr zone=uploads_by_ip:10m;
limit_conn_zone $binary_remote_addr zone=downloads_by_ip:10m;
limit_req_status 429;
limit_conn_status 429;

# since we are proxying request to nginx from caddy, access logs will contain caddy's ip address 
# as the request address so we need to use real_ip_header module to use ip address from 
# X-Forwarded-For header as a real ip address of the request
set_real_ip_from  10.0.0.0/8;
set_real_ip_from  172.16.0.0/12;
set_real_ip_from  192.168.0.0/16;
real_ip_header    X-Forwarded-For;

# note that we point uploads to port '9970', do this when you want to
# run in a configuration where you have two siad instances, one for
# downloads and one for uploads. This drastically improves the up - and
# download speed of your portal. When running your portal in this double
# siad setup, make sure only the download portal runs in 'portal mode'.
# The upload siad can be run in normal mode. Set the port to '9980' if
# you do not want to run your portal in the double siad setup.
upstream siad-upload {
	server docker-host:9970;
}

upstream siad-download {
	server docker-host:9980;
}

server {
	listen 80 default_server;
	listen [::]:80 default_server;

	# ddos protection: closing slow connections
	client_body_timeout 5s;
	client_header_timeout 5s;

	# Increase the body buffer size, to ensure the internal POSTs can always
	# parse the full POST contents into memory.
	client_body_buffer_size 128k;
	client_max_body_size 128k;

	location /blacklist {
		proxy_cache skynet;
		proxy_cache_valid any 1m; # cache blacklist for 1 minute
		proxy_pass http://siad-download/skynet/blacklist;
	}

	location /portals {
		proxy_cache skynet;
		proxy_cache_valid any 1m; # cache portals for 1 minute
		proxy_pass http://siad-download/skynet/portals;
	}

	location /stats {
		proxy_cache skynet;
		proxy_cache_valid any 1m; # cache stats for 1 minute
		proxy_pass http://siad-upload/skynet/stats;
	}

	location /statsdown {
		proxy_cache skynet;
		proxy_cache_valid any 1m; # cache stats for 1 minute
		proxy_pass http://siad-download/skynet/stats;
	}

	location /skynet/skyfile {
		limit_conn uploads_by_ip 10; # ddos protection: max 10 uploads at a time
		client_max_body_size 1000M; # make sure to limit the size of upload to a sane value
		proxy_read_timeout 600;
		proxy_request_buffering off; # stream uploaded files through the proxy as it comes in
		proxy_set_header Expect $http_expect;

		# Extract 3 sets of 2 characters from $request_id and assign to $dir1, $dir2, $dir3
		# respectfully. The rest of the $request_id is going to be assigned to $dir4.
		# We use those variables to automatically generate a unique path for the uploaded file.
		# This ensures that not all uploaded files end up in the same directory, which is something
		# that causes performance issues in the renter.
		# Example path result: /af/24/9b/c5ec894920ccc45634dc9a8065
		if ($request_id ~* "(\w{2})(\w{2})(\w{2})(\w+)") {
			set $dir1 $1;
			set $dir2 $2;
			set $dir3 $3;
			set $dir4 $4;
		}

		# proxy this call to siad endpoint (make sure the ip is correct)
		proxy_pass http://siad-upload/skynet/skyfile/$dir1/$dir2/$dir3/$dir4$is_args$args;
	}
	
	location ~ "/skynet/skyfile/(.+)" {
		limit_conn uploads_by_ip 10; # ddos protection: max 10 uploads at a time
		client_max_body_size 1000M; # make sure to limit the size of upload to a sane value
		proxy_read_timeout 600;
		proxy_request_buffering off; # stream uploaded files through the proxy as it comes in
		proxy_set_header Expect $http_expect;

		# we need to explicitly use set directive here because $1 will contain the siapath with
		# decoded whitespaces and set will re-encode it for us before passing it to proxy_pass
		set $siapath $1;

		# proxy this call to siad endpoint (make sure the ip is correct)
		proxy_pass http://siad-upload/skynet/skyfile/$siapath$is_args$args;
	}

	location ~ "^/([a-zA-Z0-9-_]{46}(/.*)?)$" {
		limit_conn downloads_by_ip 100; # ddos protection: max 100 downloads at a time

		# we need to explicitly use set directive here because $1 will contain the skylink with
		# decoded whitespaces and set will re-encode it for us before passing it to proxy_pass
		set $skylink $1;

		proxy_read_timeout 600;
		# proxy this call to siad /skynet/skylink/ endpoint (make sure the ip is correct)
		proxy_pass http://siad-download/skynet/skylink/$skylink$is_args$args;
		
		# if you are expecting large headers (ie. Skynet-Skyfile-Metadata), tune these values to your needs
		proxy_buffer_size 128k;
		proxy_buffers 4 128k;

		# cache frequent (> 10) downloads for 24 hours
		proxy_cache skynet;
		proxy_cache_key $uri;
		proxy_cache_min_uses 10;
		proxy_cache_valid 200 1440m;
	}

	location ~ "^/file/([a-zA-Z0-9-_]{46}(/.*)?)$" {
		limit_conn downloads_by_ip 100; # ddos protection: max 100 downloads at a time

		# we need to explicitly use set directive here because $1 will contain the skylink with
		# decoded whitespaces and set will re-encode it for us before passing it to proxy_pass
		set $skylink $1;

		proxy_read_timeout 600;
		# proxy this call to siad /skynet/skylink/ endpoint (make sure the ip is correct)
		# this alias also adds attachment=true url param to force download the file
		proxy_pass http://siad-download/skynet/skylink/$skylink?attachment=true&$args;

		# if you are expecting large headers (ie. Skynet-Skyfile-Metadata), tune these values to your needs
		proxy_buffer_size 128k;
		proxy_buffers 4 128k;
		
		# cache frequent (> 10) downloads for 24 hours
		proxy_cache skynet;
		proxy_cache_key $uri;
		proxy_cache_min_uses 10;
		proxy_cache_valid 200 1440m;
	}
}