esphome/docker/rootfs/etc/nginx/nginx.conf

worker_processes  1;
pid /var/run/nginx.pid;
error_log stderr;

events {
    worker_connections  1024;
}

http {
    access_log         stdout;
    include            mime.types;
    default_type       application/octet-stream;
    sendfile           on;
    keepalive_timeout  65;

    upstream esphome {
        ip_hash;
        server unix:/var/run/esphome.sock;
    }
    map $http_upgrade $connection_upgrade {
        default upgrade;
        ''      close;
    }

    server {
        server_name hassio.local;
        listen %%port%% default_server;
        root /dev/null;

        location / {
            proxy_redirect off;
            proxy_pass http://esphome;

            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection $connection_upgrade;
            proxy_set_header Authorization "";

            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $scheme;
            proxy_set_header Host $http_host;
            proxy_set_header X-NginX-Proxy true;
        }
    }
}