Add label matching for kubernetes ingests

[pnegahdar]

I want to add label (or annotation) matching to kubernetes. i.e

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: app_name
  labels:
     - traeffik/balancer-name: load-balancer-1
spec:
  rules:
  - host: news.site.com
    http:
      paths:
      - backend:
          serviceName: "app_service"
          servicePort:  80 

traefik --web --kubernetes --kubernetes.label-filter "traefik/balancer-name=load-balancer-1" would then ensure only those with that label join the balancer.

See: http://kubernetes.io/docs/user-guide/labels/#label-selectors

I know namespaces are currently supported but thats not fine-grained enough for most kube deploy systems. Thoughts on this?

[pnegahdar]

Any thoughts on this?

[emilevauge]

Hi @pnegahdar, sorry for the delay :)
I think that's a good idea! @samber is working on something similar: #311 (comment) and #342
Maybe you could exchange on this :)
We already began to use kubernetes annotation, then I would prefer to continue over using labels.
WDYT?
Thanks a lot for your help :)

[errm]

re: annotation vs labels I think that the way that k8s sees the distiction is:

• labels are for things that you may want to do selection on - they are strictly validated to a particular subset of characters.
• annotations are more a way of storing a random blob of data on to an api object, the validation is much looser.

I think labels is the way to go for this use case, as it would allow us to request the subset of ingresses we want from the apiserver without having to get them all and then filter client side.

[pnegahdar]

I agree and seems like the kubernetes docs agree too: http://kubernetes.io/docs/user-guide/annotations/

[emilevauge]

You're right, I read the doc too quickly :) Let's go on labels !

[errm]

@pnegahdar is this something that you are still working on?

[pnegahdar]

Actually scheduled doing it today and tomorrow. Hoping to make the 1.0 cut.

[errm]

@pnegahdar unless you already have some work in progress on this, I am thinking of picking this one up sometime next week...

[pnegahdar]

@errm Wrote a starting implementation. A bit stuck on how to unit test sanely -- kubernetes has a somewhat complex label selector syntax (http://kubernetes.io/docs/user-guide/labels/) that is somewhat hard to effectively mock out.

[cameronattard]

Will this be included in an upcoming release?