explain how to run linuxfr with rootless containers

Author: Trim

Docker.md

@@ -25,12 +25,23 @@ docker-compose run linuxfr.org bin/rails db:setup
 Finally, the environment is ready and you can open [http://dlfp.lo](http://dlfp.lo)
 in your favorite browser.
 
-Note: to be able to access this URL, you'll need to add the following line
-into the `/etc/hosts` file of your machine:
+Notes:
+
+1. to be able to access this URL, you'll need to add the following line
+  into the `/etc/hosts` file of your machine:
+  
+  ```
+  127.0.0.1 dlfp.lo image.dlfp.lo
+  ```
+
+2. for [rootless containers](https://rootlesscontaine.rs/), you'll need
+  to allow standard users to listen on ports less than 1024
+  (this is needed because linuxfr use port 80 and 443):
+
+  ```sh
+  sudo sysctl net.ipv4.ip_unprivileged_port_start=80
+  ```
 
-```
-127.0.0.1 dlfp.lo image.dlfp.lo
-```
 
 Personalize configuration
 =========================

docker-compose.yaml

@@ -10,10 +10,10 @@ services:
     volumes:
       # Share host directories so, the developer can edit them
       # and see the result without need to restart the container
-      - ./app:/linuxfr.org/app
-      - ./db:/linuxfr.org/db
-      - ./public:/linuxfr.org/public
-      - ./test:/linuxfr.org/test
+      - ./app:/linuxfr.org/app:Z
+      - ./db:/linuxfr.org/db:Z
+      - ./public:/linuxfr.org/public:Z
+      - ./test:/linuxfr.org/test:Z
       # uploads are shared with the nginx service
       - data-uploads:/linuxfr.org/uploads
     tmpfs:
@@ -45,8 +45,8 @@ services:
     env_file:
       - deployment/default.env
     volumes:
-      - ./deployment/nginx/templates:/etc/nginx/templates
-      - ./public/fonts:/var/linuxfr/fonts
+      - ./deployment/nginx/templates:/etc/nginx/templates:Z
+      - ./public/fonts:/var/linuxfr/fonts:Z
       - data-uploads:/var/linuxfr/uploads
     ports:
       - "80:80"