Feature request: Export metrics to Prometheus

[qdm12]

1. What's the feature?

• Export metrics to Prometheus on:
  • Scrap iptables data to get network information (blocked data, vpn'ed data etc.)
  • Health information, such as when connectivity drops
  • VPN server information
  • the Go written Shadowsocks
  • the (Go) HTTP proxy
  • the Go written DNS server (blocked by Feature request: DNS over HTTPS in Go to replace Unbound #137)
  • the numbers found from Feature request: vnstat like traffic monitor #251
  • Maybe add some bandwidth tests but that depends on the test server, so maybe not
• Add instructions on how to set this up with Grafana to have nice graphs
• Add a Grafana dashboard example to the repository

2. Why do you need this feature?

Because metrics are fun

3. Extra information?

[dorsegal]

That would be awesome!

[SR-G]

So any news on this ?
I would also find this very helpful. Especially the "connection lost", "connected country", ... informations.

Maybe "start small" / do "baby steps" regarding this new evolution, as the feature list is quite long and may be overhelming ?

What would be the "architecture" for these metrics ? Something embedded inside gluetun code itself (and exposed by ... the control server, on a /metrics path, maybe ?), or an external separated program (a gluetun-exporter go standalone project, able to externally gather (in some way) all the metrics) ?