Conflict Management

Navecd uses Server-Side Apply to maintain cluster states and SSA provides a mechanism to track changes to a manifest's fields, which is called Field Management. Navecd takes Ownership of all manifest's fields declared in Git. This makes Navecd a Field Manager.

Any change to Navecd managed fields will be overwritten by Navecd and if you commit to using GitOps as your way to deploy to Kubernetes, then manual changes to your cluster are an anti pattern. But there are cases where Field Managers in your cluster try to take over management of certain fields. The most prominent situation probably is a Horizontal Pod Autoscaler mutating the replicas count. In order to avoid fighting over conflicting fields, you can tell Navecd to ignore them, so that the competing manager can take over.

myapp/deployment.cue

package myapp

import (
  "github.com/kharf/navecd/schema/component"
)

deployment: component.#Manifest & {
  content: {
    apiVersion: "apps/v1"
    kind:       "Deployment"
    metadata: {
      name:      "my-deployment"
      namespace: ns.content.metadata.name
      labels:    _primaryLabels
    }
    spec: {
      selector: matchLabels: _primaryLabels
      replicas: 1 @ignore(conflict)
  ...
    }
  }
}

@ignore(conflicts) is a custom CUE build attribute, implemented and understood by Navecd. You can attach it to fields or declarations to resolve field conflicts.