[Feature] Naming labels based on regex capture groups

[illrill]

This feature request is for the ability to use regex capture groups to name the labels dynamically.

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Imagine the following repository folder structure and I want all PR's to have an area/<area> label, which value should be based on the subfolder that the PR brings changes to.

k8s/ingress/...
k8s/rbac/...
k8s/config/...
k8s/dns/...
k8s/istio/...
network/...

Currently, I need to configure each possible label manually:

labels:
- label: "area/k8s-ingress"
  files:
  - "k8s/ingress/.*"
- label: "area/k8s-rbac"
  files:
  - "k8s/rbac/.*"
- label: "area/k8s-config"
  files:
  - "k8s/config/.*"
- label: "area/k8s-dns"
  files:
  - "k8s/dns/.*"
- label: "area/k8s-istio"
  files:
  - "k8s/istio/.*"
- label: "area/network"
  files:
  - "network/.*"

With the ability to use regex capture groups to name the labels dynamically, my configuration could be reduced to:

labels:
- label: "area/k8s-$1"
  files:
  - "k8s/(.*)/.*"
- label: "area/network"
  files:
  - "network/.*"

---

Nice to see that your back at it and releasing new features @srvaroa 🔥We love this project in our team.

[srvaroa]

Thanks @illrill, glad you're finding it useful. Looks like a good feature!