silence-operator release v0.17.0

Added

• Add advanced filtering capabilities for both v1alpha1 and v1alpha2 controllers:
  • Add silence selector feature to filter Silence resources by labels (configure via --silence-selector flag).
  • Add namespace selector for v1alpha2 controller to restrict watched namespaces (configure via --namespace-selector flag).
• Allow filtering of Silence custom resources based on a label selector. The operator will only process Silence CRs that match the selector provided via the --silence-selector command-line flag or the silenceSelector Helm chart value. If no selector is provided, all Silence CRs are processed.
• Add new observability.giantswarm.io/v1alpha2 API with namespace-scoped Silence CRD for improved multi-tenancy.
  • Add MatchType enum field using Alertmanager operator symbols (=, !=, =~, !~) for intuitive matching logic.
  • Add SilenceV2Reconciler controller to handle v1alpha2 resources while maintaining full backward compatibility with v1alpha1.
  • Add comprehensive field validation: matcher names (1-256 chars), values (max 1024 chars), minimum 1 matcher required.
  • Add printer columns to v1alpha2 CRD for better kubectl get silences output showing Age.
• Add automated migration script (hack/migrate-silences.sh) for v1alpha1 to v1alpha2 conversion.
  • Automatically converts boolean matcher fields (isRegex/isEqual) to enum format (matchType).
  • Intelligently preserves user annotations/labels while filtering out Kubernetes and FluxCD system metadata.
  • Supports dry-run mode for safe migration testing.
• Add comprehensive migration documentation (MIGRATION.md) with examples and best practices.
• Add clean service layer architecture (pkg/service/) separating business logic from Kubernetes controller concerns.

Changed

• BREAKING (v1alpha2 only): Replace isRegex and isEqual boolean fields with single matchType enum field using Alertmanager symbols.
• BREAKING (v1alpha2 only): Change from cluster-scoped to namespace-scoped resources for better multi-tenancy and RBAC isolation.
• BREAKING (v1alpha2 only): Remove deprecated fields in v1alpha2: targetTags, owner, postmortem_url, and issue_url for cleaner API design.
• Improve code organization with dependency injection and clear separation between controller logic and business logic.

Deprecated

• The monitoring.giantswarm.io/v1alpha1 API is now considered legacy. New deployments should use observability.giantswarm.io/v1alpha2. Migration Note: Existing v1alpha1 silences continue to work unchanged. Use the automated migration script and see MIGRATION.md for detailed guidance.