Nginx Proxy for S3

An Nginx proxy in front of a bucket lets you serve files from your own domain (for example, https://cdn.example.com/...), cache them on the server and hide S3 service headers.

Before You Start

• a VM with Nginx and a domain pointing to its public IP address;
• public read access to the files you want to serve — see Bucket Policy.

Nginx Configuration

Create /etc/nginx/conf.d/s3-proxy.conf. Replace cdn.example.com with your domain and my-bucket with the name of your bucket:

proxy_cache_path /var/cache/nginx/s3 levels=1:2 keys_zone=s3cache:10m
                 max_size=10g inactive=7d use_temp_path=off;

server {
    listen 80;
    server_name cdn.example.com;

    location / {
        limit_except GET HEAD { deny all; }

        proxy_pass https://s3.uzcstorage.uz/my-bucket/;
        proxy_set_header Host s3.uzcstorage.uz;
        proxy_ssl_server_name on;
        proxy_set_header Authorization "";

        proxy_hide_header x-amz-id-2;
        proxy_hide_header x-amz-request-id;
        proxy_hide_header x-rgw-object-type;
        proxy_hide_header Set-Cookie;
        proxy_ignore_headers Set-Cookie;

        proxy_cache s3cache;
        proxy_cache_valid 200 304 24h;
        proxy_cache_valid 404 1m;
        proxy_cache_use_stale error timeout updating http_500 http_502 http_503 http_504;
        add_header X-Cache-Status $upstream_cache_status;
    }
}

Check the configuration and reload Nginx:

sudo nginx -t && sudo systemctl reload nginx

Get an HTTPS certificate, for example with Let’s Encrypt:

sudo apt install certbot python3-certbot-nginx
sudo certbot --nginx -d cdn.example.com

Check: curl -I https://cdn.example.com/public/logo.png. On the second request, the X-Cache-Status: HIT header shows that the file was served from the cache.