A docker host serving Rails and PHP containers.

rails+php-on-docker.diag

blockdiag {
  orientation = portrait;
  default_shape = roundedbox;
  default_group_color = "#808080";

  user [shape = actor]
  inet [shape = cloud];

  user -> inet

  inet -> nginx [label = "HTTP(S)"];
  inet -> docker-registry [label = "(deploy)", style = "dotted"]

  group host {
    label = "*.example.com";

    nginx [label = "nginx (Reverse Proxy)"]
    nginx -> rails-nginx, php-apache [label = "HTTP"];

    docker-registry -> docker
    group docker-registry {
        color = "#004040";
        docker-registry;
    }

    group rails-container {
      color = "#00C0C0";
      rails-nginx  [label = "nginx"];
      rails-nginx -> rails-puma, rails-static;
      rails-nginx -> rails-puma [label = "HTTP"];

      rails-puma [label = "puma"];
      rails-puma -> rails;

      rails-static [label = "static files"];
      rails [label = "Rails"];
    }

    
    php-fpm -> php;
    group php-container {
      color = "#00C0C0";
      php-apache [label = "Apache"];
      php-apache -> php-fpm, php-static;
      php-apache -> php-fpm [label = "FastCGI"];

      php-fpm [label = "PHP FPM"];
      php-fpm -> php;

      php-static [label = "static files"];
      php [label = "PHP"];
    }

    rails, php -> mysql, postfix;

    group mysql-container {
      color = "#004040";
      mysql [shape = "flowchart.database", label = "MySQL"];
    }
    group postfix-container {
      color = "#004040";
      postfix [shape = "mail", label = "Postfix"];
    }
  }
}

Result: