Prometheus SD through REST API

jmara

Hi,

I was wondering if we could get a REST API Endpoint to discover vms via the prometheus build-in http_sd?

As a starting point it would be nice the get the ips and pool association of vms through the /vms call so that it would be possible to write a wrapper script to match the http_sd format.

Or is this possible and I haven't found the correct fields yet?

Cheers,
Jan

olivierlambert

Hi,

Can you be more specific? I never heard about http_sd

jmara

@olivierlambert sure its a new service discovery plugin in the prometheus core which scrapes http endpoints:
https://prometheus.io/docs/prometheus/latest/http_sd/

It requires this json format:

[
  {
    "targets": [ "<host>", ... ],
    "labels": {
      "<labelname>": "<labelvalue>", ...
    }
  },
  ...
]

olivierlambert

@julien-f do you think it's something doable at some point?

jmara

@olivierlambert As said, I would be a starting point if the fields of the /vms call will be extended to include ipaddesses, pool_name/id and maybe host_affinity

olivierlambert

I think it's already the case if you add the value in the query string (but I might be wrong). That's why I'm asking @julien-f ^^

olivierlambert

Here is what you asked:

curl -b authenticationToken=xxxbak 'http://xxxx/rest/v0/vms/?fields=name_label,%24pool,addresses,affinityHost'

Which is returning this for me:

  {
    "name_label": "XOA 🎷",
    "$pool": "xxxxxxxx-xxxx-xxxx-xxxx-2c519aa297e7",
    "mainIpAddress": "192.168.x.x",
    "addresses": {
      "0/ipv4/0": "192.168.x.x",
      "0/ipv6/0": "fe80::xxxx:xxxx:xxxx:xxxx"
    },
    "affinityHost": "xxxxxxxx-xxxx-xxxx-xxxx-0dc8858f6686",
    "href": "/rest/v0/vms/xxxxxxxx-xxxx-xxxx-xxxx-a7a9306b347b"
  }

Note: affinityHost is missing if it's not set.

Note 2: you can use mainIpAddress field, which is the helper showing the first IP address visible from the tools.

olivierlambert

Also, please keep us posted on this, I'm curious about the outcome and your use case It's an interesting way of leveraging our API!

jmara

@olivierlambert Uh very nice now I got something to play with in the evening I'll let you know once I've created a PoC

olivierlambert