Deploying Plone 6.x using Docker Images plone-frontend and plone-backend having trouble with :null:3000 part in the URL

Plone Support Deployment & hosting
1

I'm trying to build Plone with docker-compose and the plone6-backend and plone6-frontend Docker Images.
My docker-compose.yml File looks like this:

version: '3'

services:
  plone6-backend:
    image: plone/plone-backend:6.0
    container_name: plone6-backend
    restart: unless-stopped
    ports:
      - 8080:8080
    environment:
      - SITE=Plone
      - CORS_ALLOW_ORIGIN='*'
      - LISTEN_PORT=8080
  plone6-frontend:
    image: plone/plone-frontend:latest
    container_name: plone6-frontend
    restart: unless-stopped
    ports:
      - 3000:3000
    depends_on:
      - plone6-backend
    environment:
      - RAZZLE_API_PATH=https://[$ONLINE_URL]/
      - RAZZLE_INTERNAL_API_PATH=http://backend:8080/Plone
    links:
      - plone6-backend:backend

I'm using an apache2 Server with the following Configuration:

<VirtualHost [$ONLINE_URL]:80>
    ServerName [$ONLINE_URL]
    ServerAlias [$ONLINE_URL]

    ProxyPass / https://localhost:3000/
    ProxyPassReverse / https://localhost:3000/

</VirtualHost>

<IfModule mod_ssl.c>

    <VirtualHost [$ONLINE_URL]:443>
        ServerName [$ONLINE_URL]
        ServerAlias [$ONLINE_URL]

        SSLProxyEngine On
        ProxyPass / http://localhost:3000/
        ProxyPassReverse / http://localhost:3000/
        ProxyPass /++api++ http://localhost:8080/
        ProxyPassReverse /++api++ http://localhost:8080/

        SSLEngine on
        SSLCertificateFile [$CERT_FILE]
        SSLCertificateKeyFile [$CERT_KEY_FILE]
    </VirtualHost>

</IfModule>

The Problem is: When I start the Server, wait until it's completely up and healthy and open the Online URL in the Browser and click on the Login Link I get the following URL in the Browser:
https://[$ONLINE_URL]/login?return_url=:null:3000
Where does that ':null:3000' part after ?return_url come from, what do I have to configure in my docker-compose.yml to get rid of it?

Do you have other suggestions how I can improve the "Configuration" (i.e. the docker-compose.yml File or the Apache Configuration?

2

I've found a way to setup a Plone 6 Website with docker-compose.yml and apache2 now, including an nginx in the docker stack. It also uses a postgres Database in the Backend, which is also part of the docker stack.
Does anybody know, why the Backend Container says:

backend_1    | Creating Plone volto SITE: Plone
backend_1    | Aditional profiles:
backend_1    | THIS IS NOT MEANT TO BE USED IN PRODUCTION
backend_1    | Read about it: https://6.docs.plone.org/install/containers/images/backend.html

Generally asked:
Is it a good idea to make the plone-backend directly publicly available (with another subdmain), or should this be avoided due to security reasons?

In my special case I'm using one subdomain for the Plone Frontend and another one for the Plone Backend.

3

There are at least three posts on this forum that discuss a similar issue. Did you see these:

https://community.plone.org/t/issue-with-deploying-plone-6-on-plesk-server

Apparently, you should include RAZZLE_PROXY_REWRITE_TARGET in your docker configuration. Documented here: How to use environment variables — Plone Documentation v6