refactor: Move matchers to own package and add tests (#125)

Author: jimmidyson

pkg/handlers/httpproxy/matcher.go renamed to pkg/capi/clustertopology/patches/matchers/match.go

@@ -6,7 +6,7 @@
 // See: https://github.com/kubernetes-sigs/cluster-api/blob/46412f0a4ea65d8f02478d2ad09ce12925485f56/internal/controllers/topology/cluster/patches/inline/json_patch_generator.go#L125
 //
 //nolint:lll // Long URLs in comments above. Adding nolint:lll here because it doesn't work in comment lines. See: https://github.com/golangci/golangci-lint/issues/3983
-package httpproxy
+package matchers
 
 import (
 	"strconv"
@@ -19,65 +19,52 @@ import (
 	"sigs.k8s.io/cluster-api/exp/runtime/topologymutation"
 )
 
-func matchSelector(
+func MatchesSelector(
 	selector clusterv1.PatchSelector,
 	obj runtime.Object,
 	holderRef *runtimehooksv1.HolderReference,
 	templateVariables map[string]apiextensionsv1.JSON,
 ) bool {
-	if !matchGVK(selector.APIVersion, selector.Kind, obj) {
+	if !MatchesGVK(selector.APIVersion, selector.Kind, obj) {
 		return false
 	}
 
-	if selector.MatchResources.InfrastructureCluster {
-		if !matchInfrastructure(holderRef) {
-			return false
-		}
+	if selector.MatchResources.InfrastructureCluster && MatchesInfrastructure(holderRef) {
+		return true
 	}
 
-	if selector.MatchResources.ControlPlane {
-		if !matchControlPlane(holderRef) {
-			return false
-		}
+	if selector.MatchResources.ControlPlane && MatchesControlPlane(holderRef) {
+		return true
 	}
 
-	if selector.MatchResources.MachineDeploymentClass != nil {
-		if !matchMachineDeploymentClass(
+	if selector.MatchResources.MachineDeploymentClass != nil &&
+		MatchesMachineDeploymentClass(
 			holderRef,
 			selector.MatchResources.MachineDeploymentClass.Names,
 			templateVariables,
 		) {
-			return false
-		}
+		return true
 	}
 
-	return true
+	return false
 }
 
-// Check if the apiVersion and kind are matching.
-func matchGVK(apiVersion, kind string, obj runtime.Object) bool {
-	objAPIVersion, objKind := obj.GetObjectKind().GroupVersionKind().ToAPIVersionAndKind()
-	// Check if the apiVersion and kind are matching.
-	if objAPIVersion != apiVersion {
-		return false
-	}
-	if objKind != kind {
-		return false
-	}
-	return true
+// MatchesGVK checks if the apiVersion and kind are matching.
+func MatchesGVK(apiVersion, kind string, obj runtime.Object) bool {
+	gvk := obj.GetObjectKind().GroupVersionKind()
+
+	return gvk.GroupVersion().String() == apiVersion && gvk.Kind == kind
 }
 
-// Check if the request is for an InfrastructureCluster.
-func matchInfrastructure(holderRef *runtimehooksv1.HolderReference) bool {
-	// Cluster.spec.infrastructureRef holds the InfrastructureCluster.
-	if holderRef.Kind == "Cluster" && holderRef.FieldPath == "spec.infrastructureRef" {
-		return true
-	}
-	return false
+// MatchesInfrastructure checks if the request is for an InfrastructureCluster.
+// Cluster.spec.infrastructureRef holds the InfrastructureCluster.
+func MatchesInfrastructure(holderRef *runtimehooksv1.HolderReference) bool {
+	return holderRef.Kind == "Cluster" && holderRef.FieldPath == "spec.infrastructureRef"
 }
 
-// Check if the request is for a ControlPlane or the InfrastructureMachineTemplate of a ControlPlane.
-func matchControlPlane(holderRef *runtimehooksv1.HolderReference) bool {
+// MatchesControlPlane checks if the request is for a ControlPlane or the InfrastructureMachineTemplate of a
+// ControlPlane.
+func MatchesControlPlane(holderRef *runtimehooksv1.HolderReference) bool {
 	// Cluster.spec.controlPlaneRef holds the ControlPlane.
 	if holderRef.Kind == "Cluster" && holderRef.FieldPath == "spec.controlPlaneRef" {
 		return true
@@ -92,9 +79,9 @@ func matchControlPlane(holderRef *runtimehooksv1.HolderReference) bool {
 	return false
 }
 
-// Check if the request is for a BootstrapConfigTemplate or an InfrastructureMachineTemplate
-// of one of the configured MachineDeploymentClasses.
-func matchMachineDeploymentClass(
+// MatchesMachineDeploymentClass checks if the request is for a BootstrapConfigTemplate or an
+// InfrastructureMachineTemplate of one of the configured MachineDeploymentClasses.
+func MatchesMachineDeploymentClass(
 	holderRef *runtimehooksv1.HolderReference,
 	names []string,
 	templateVariables map[string]apiextensionsv1.JSON,
@@ -130,5 +117,6 @@ func matchMachineDeploymentClass(
 			}
 		}
 	}
+
 	return false
 }