Feature request: Webhook call when forwarded port change

[antanilol]

What's the feature 🧐

I use gluetun with PIA and forwarding. I have seen many ways to read the forwarded port from gluetun (most of them using the fwd_port file, wich I read is being deprecated) but I think the best way would be gluetun that makes a web request by itself calling a user-configured webhook when the port is being changed and maybe at the start of gluetun too.
Making the web request entirely configurable with a template inside the docker compose file (or a separate config file) would be ideal.
I understand it can take some time to implement such a thing, so a simple GET or POST request with the forwarded port to a user-configurable endpoint it'd be nice too.

I found a program (written in Go) that implement this, if you want to take a look

Thank you for your work!

Extra information and references

No response

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[qdm12]

You can now use VPN_PORT_FORWARDING_UP_COMMAND, see https://github.com/qdm12/gluetun-wiki/blob/main/setup/advanced/vpn-port-forwarding.md#custom-port-forwarding-up-command
For example with wget which is built-in:

VPN_PORT_FORWARDING_UP_COMMAND=wget -O- --post-data='{"some data to post..."}' 'https://example.com:9000'