fix: unmarshals generic cluster config with a check

Author: faiq

pkg/webhook/preflight/generic/checker.go

@@ -15,10 +15,14 @@ import (
 )
 
 var Checker = &genericChecker{
-	registryCheckFactory: newRegistryCheck,
+	registryCheckFactory:      newRegistryCheck,
+	configurationCheckFactory: newConfigurationCheck,
 }
 
 type genericChecker struct {
+	configurationCheckFactory func(
+		cd *checkDependencies,
+	) preflight.Check
 	registryCheckFactory func(
 		cd *checkDependencies,
 	) []preflight.Check
@@ -41,7 +45,11 @@ func (g *genericChecker) Init(
 		cluster: cluster,
 		log:     ctrl.LoggerFrom(ctx).WithName("preflight/generic"),
 	}
-	checks := []preflight.Check{}
+	checks := []preflight.Check{
+		// The configuration check must run first, because it initializes data used by all other checks.
+		g.configurationCheckFactory(cd),
+	}
 	checks = append(checks, g.registryCheckFactory(cd)...)
+	cd.log.Info("returning checks", "checks", checks)
 	return checks
 }

pkg/webhook/preflight/generic/registry.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"regexp"
 
+	"github.com/go-logr/logr"
 	"github.com/regclient/regclient"
 	"github.com/regclient/regclient/config"
 	"github.com/regclient/regclient/types/ping"
@@ -36,13 +37,15 @@ type registryCheck struct {
 	kclient               ctrlclient.Client
 	cluster               *clusterv1.Cluster
 	regClientPingerGetter regClientPingerFactory
+	log                   logr.Logger
 }
 
 func (r *registryCheck) Name() string {
 	return "RegistryCredentials"
 }
 
 func (r *registryCheck) Run(ctx context.Context) preflight.CheckResult {
+	r.log.Info("Running registry check")
 	if r.registryMirror != nil {
 		return r.checkRegistry(
 			ctx,
@@ -186,6 +189,7 @@ func newRegistryCheck(
 			registryMirror:        cd.genericClusterConfigSpec.GlobalImageRegistryMirror.DeepCopy(),
 			cluster:               cd.cluster,
 			regClientPingerGetter: defaultRegClientGetter,
+			log:                   cd.log,
 		})
 	}
 	if cd.genericClusterConfigSpec != nil && len(cd.genericClusterConfigSpec.ImageRegistries) > 0 {
@@ -200,6 +204,7 @@ func newRegistryCheck(
 				imageRegistry:         registry.DeepCopy(),
 				cluster:               cd.cluster,
 				regClientPingerGetter: defaultRegClientGetter,
+				log:                   cd.log,
 			})
 		}
 	}

pkg/webhook/preflight/generic/spec.go

@@ -0,0 +1,55 @@
+package generic
+
+import (
+	"context"
+	"fmt"
+
+	carenv1 "github.com/nutanix-cloud-native/cluster-api-runtime-extensions-nutanix/api/v1alpha1"
+	"github.com/nutanix-cloud-native/cluster-api-runtime-extensions-nutanix/api/variables"
+	"github.com/nutanix-cloud-native/cluster-api-runtime-extensions-nutanix/pkg/webhook/preflight"
+)
+
+type configurationCheck struct {
+	result preflight.CheckResult
+}
+
+func (c *configurationCheck) Name() string {
+	return "GenericConfiguration"
+}
+
+func (c *configurationCheck) Run(_ context.Context) preflight.CheckResult {
+	return c.result
+}
+
+func newConfigurationCheck(
+	cd *checkDependencies,
+) preflight.Check {
+	genericClusterConfigSpec := &carenv1.GenericClusterConfigSpec{}
+	configurationCheck := &configurationCheck{
+		result: preflight.CheckResult{
+			Allowed: true,
+		},
+	}
+	err := variables.UnmarshalClusterVariable(
+		variables.GetClusterVariableByName(
+			carenv1.ClusterConfigVariableName,
+			cd.cluster.Spec.Topology.Variables,
+		),
+		genericClusterConfigSpec,
+	)
+	if err != nil {
+		configurationCheck.result.Allowed = false
+		configurationCheck.result.Error = true
+		configurationCheck.result.Causes = append(configurationCheck.result.Causes,
+			preflight.Cause{
+				Message: fmt.Sprintf("Failed to unmarshal cluster variable %s: %s",
+					carenv1.ClusterConfigVariableName,
+					err,
+				),
+				Field: "cluster.spec.topology.variables[.name=clusterConfig].genericClusterConfigSpec",
+			},
+		)
+	}
+	cd.genericClusterConfigSpec = genericClusterConfigSpec
+	return configurationCheck
+}