Some development testing is easier with farmOS on an https:// endpoint. A separate Nginx reverse proxy provides a simple way to achieve this without any changes to the Apache configuration that runs in the farmOS Docker container.

First, generate self-signed SSL certificate files into an ssl directory, from the directory that your docker-compose.yml file is in:

mkdir ssl
openssl req -newkey rsa:4096 -x509 -sha256 -nodes -out ssl/openssl.crt -keyout ssl/openssl.key

Create a file called nginx.conf alongside docker-compose.yml:

events {}
http {
  server {
      listen 80 default_server;
      listen [::]:80 default_server;
      server_name _;
      return 301 https://$host$request_uri;
  server {
    server_name localhost;
    listen 443 ssl;
    ssl_certificate /etc/nginx/ssl/openssl.crt;
    ssl_certificate_key /etc/nginx/ssl/openssl.key;
    location / {
      proxy_set_header Host $http_host;
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-Host $http_host;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header X-Forwarded-Proto $scheme;
      proxy_buffer_size 128k;
      proxy_buffers 4 256k;
      proxy_busy_buffers_size 256k;
      proxy_pass http://www;

Add the following lines to www/web/sites/default/settings.php:

$settings['reverse_proxy'] = TRUE;
$settings['reverse_proxy_addresses'] = [$_SERVER['REMOTE_ADDR']];
$settings['reverse_proxy_trusted_headers'] = \Symfony\Component\HttpFoundation\Request::HEADER_X_FORWARDED_ALL;

Add the following service to your local docker-compose.yml file:

    image: nginx
      - www
      - '80:80'
      - '443:443'
      - './nginx.conf:/etc/nginx/nginx.conf'
      - './ssl:/etc/nginx/ssl'

Also remove port 80 from the www service:

      - '80:80'

Finally, start the Docker services:

docker compose up

farmOS is now accessible via https://localhost.