limit_req_zone $binary_remote_addr zone=rpc_per_ip:10m rate=10r/s;

upstream anvil_rpc {
    server anvil:8545;
    keepalive 16;
}

server {
    listen 80;
    server_name _;

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

    location = /healthz {
        access_log off;
        return 200 "ok\n";
    }

    location / {
        if ($request_method = OPTIONS) {
            add_header Access-Control-Allow-Origin "*" always;
            add_header Access-Control-Allow-Methods "POST, OPTIONS" always;
            add_header Access-Control-Allow-Headers "content-type" always;
            add_header Access-Control-Max-Age 86400 always;
            return 204;
        }

        limit_req zone=rpc_per_ip burst=20 nodelay;
        limit_except POST {
            deny all;
        }

        proxy_http_version 1.1;
        proxy_set_header Connection "";
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_read_timeout 60s;
        proxy_send_timeout 60s;

        add_header Access-Control-Allow-Origin "*" always;
        proxy_pass http://anvil_rpc;
    }
}