The HTTP API exposed with js-ipfs can also be used for exposing metrics about the running js-ipfs node and other Node.js metrics.
To enable it, you need to set the environment variable IPFS_MONITORING
(any value). E.g.
$ IPFS_MONITORING=true jsipfs daemon
Once the environment variable is set and the js-ipfs daemon is running, you can get the metrics (in prometheus format) by making a GET request to the following endpoint:
http://localhost:5002/debug/metrics/prometheus