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]