Docker needs a specific configuration to pull images behind a proxy

[nqb]

Is your feature request related to a problem? Please describe.
If your PacketFence server reach Internet through a proxy, installation will fail because pull of container images doesn't use system proxy.

https://docs.docker.com/config/daemon/systemd/#httphttps-proxy

Describe the solution you'd like
Create a pre-start script in Docker which:

• detect if a proxy is defined on the system (through environment variables)
• create an environment file read by Docker to use these variables

Important: ISO installer should also work if somebody configured a proxy on the system.

Additional context
Current workaround:

1. systemctl edit docker

[Service]
Environment="NO_PROXY=localhost, 127.0.0.0/8, ::1"
Environment="HTTP_PROXY=http://proxy.example.lan:9090"
Environment="HTTPS_PROXY=http://proxy.example.lan:9090"

3. systemctl daemon-reload
4. systemctl restart docker

[nqb]

It's necessary to use same recipe if you run Monit behind a proxy in order to have update.sh working. If you put your HTTP variables in local-vars, it will only work for run-all.sh script but not for update.sh itself.

[stegar123]

docker version 23.0 and bigger support proxy env variable

https://docs.docker.com/engine/reference/commandline/dockerd/#proxy-configuration