Hello, I will be interested to use a monitoring endpoint on martin. Of course I'm ready to work on it.

The need is to have some sort of monitoring endpoint to retrieve some metrics.
I would be interested for:

• metrics linked to the web server
• metrics linked to the connexion martin has to postgres and some performance insight
• metrics linked to the duration of the tile generating process
• any others that should be discussed

I'm thinking this can be behind a feature flag in order to give the user a choice.

What are your take on this?

Implementation details:

we have the choice between two prometheus instrumentation libraries

• https://github.com/prometheus/client_rust
• https://github.com/tikv/rust-prometheus (seems to be more popular)

the https://github.com/tikv/rust-prometheus library is compatible with the actix web instrumentation library https://github.com/nlopes/actix-web-prom