bring back support for mutations, remove Rudi support

On-behalf-of: @SAP [email protected]

Author: xrstf

internal/controller/sync/controller.go

@@ -93,7 +93,7 @@ func Create(
 	}
 
 	// create the syncer that holds the meat&potatoes of the synchronization logic
-	mutator := mutation.NewMutator(nil) // pubRes.Spec.Mutation
+	mutator := mutation.NewMutator(pubRes.Spec.Mutation)
 	syncer, err := sync.NewResourceSyncer(log, localManager.GetClient(), virtualWorkspaceCluster.GetClient(), pubRes, localCRD, apiExportName, mutator, stateNamespace, agentName)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create syncer: %w", err)

internal/mutation/mutation.go

@@ -28,7 +28,6 @@ import (
 	"github.com/Masterminds/sprig/v3"
 	"github.com/tidwall/gjson"
 	"github.com/tidwall/sjson"
-	"go.xrstf.de/rudi"
 
 	syncagentv1alpha1 "github.com/kcp-dev/api-syncagent/sdk/apis/syncagent/v1alpha1"
 )
@@ -46,11 +45,6 @@ func ApplyResourceMutations(value any, mutations []syncagentv1alpha1.ResourceMut
 }
 
 func ApplyResourceMutation(value any, mut syncagentv1alpha1.ResourceMutation, ctx *TemplateMutationContext) (any, error) {
-	// for Rudi scripts we can skip all the JSON encoding/decoding
-	if mut.Rudi != nil {
-		return applyResourceRudiMigration(value, *mut.Rudi, ctx)
-	}
-
 	// encode current value as JSON
 	encoded, err := json.Marshal(value)
 	if err != nil {
@@ -82,33 +76,10 @@ func applyResourceMutationToJSON(jsonData string, mut syncagentv1alpha1.Resource
 	case mut.Regex != nil:
 		return applyResourceRegexMutation(jsonData, *mut.Regex)
 	default:
-		return "", errors.New("must use either Rudi, regex, template or delete mutation")
+		return "", errors.New("must use either regex, template or delete mutation")
 	}
 }
 
-func applyResourceRudiMigration(value any, mut syncagentv1alpha1.ResourceRudiMutation, ctx *TemplateMutationContext) (any, error) {
-	program, err := rudi.Parse("myscript", mut.Script)
-	if err != nil {
-		return nil, fmt.Errorf("invalid script: %w", err)
-	}
-
-	funcs := rudi.NewBuiltInFunctions()
-	vars := rudi.NewVariables()
-
-	if ctx != nil {
-		vars.
-			Set("localObj", ctx.LocalObject).
-			Set("remoteObj", ctx.RemoteObject)
-	}
-
-	processed, _, err := program.Run(value, vars, funcs)
-	if err != nil {
-		return nil, fmt.Errorf("script failed: %w", err)
-	}
-
-	return processed, nil
-}
-
 func applyResourceDeleteMutation(jsonData string, mut syncagentv1alpha1.ResourceDeleteMutation) (string, error) {
 	jsonData, err := sjson.Delete(jsonData, mut.Path)
 	if err != nil {

internal/mutation/mutation_test.go

@@ -187,89 +187,6 @@ func TestApplyResourceMutation(t *testing.T) {
 			},
 			expected: `{"spec":[1,3]}`,
 		},
-
-		// Rudi
-
-		{
-			name:      "Rudi: empty script",
-			inputData: `{"spec":{"secretName":"foo"}}`,
-			mutation: syncagentv1alpha1.ResourceMutation{
-				Rudi: &syncagentv1alpha1.ResourceRudiMutation{
-					Script: `.`,
-				},
-			},
-			expected: `{"spec":{"secretName":"foo"}}`,
-		},
-		{
-			name:      "Rudi: set one new key",
-			inputData: `{"spec":{"secretName":"foo"}}`,
-			mutation: syncagentv1alpha1.ResourceMutation{
-				Rudi: &syncagentv1alpha1.ResourceRudiMutation{
-					Script: `(set! .foo "bar")`,
-				},
-			},
-			expected: `{"foo":"bar","spec":{"secretName":"foo"}}`,
-		},
-		{
-			name:      "Rudi: update existing key",
-			inputData: `{"spec":{"secretName":"foo"}}`,
-			mutation: syncagentv1alpha1.ResourceMutation{
-				Rudi: &syncagentv1alpha1.ResourceRudiMutation{
-					Script: `(set! .spec.secretName "bar")`,
-				},
-			},
-			expected: `{"spec":{"secretName":"bar"}}`,
-		},
-		{
-			name:      "Rudi: remove a key",
-			inputData: `{"spec":{"secretName":"foo"}}`,
-			mutation: syncagentv1alpha1.ResourceMutation{
-				Rudi: &syncagentv1alpha1.ResourceRudiMutation{
-					Script: `(delete! .spec.secretName)`,
-				},
-			},
-			expected: `{"spec":{}}`,
-		},
-		{
-			name:      "Rudi: result value is ignored, only document counts",
-			inputData: `{"spec":{"secretName":"foo"}}`,
-			mutation: syncagentv1alpha1.ResourceMutation{
-				Rudi: &syncagentv1alpha1.ResourceRudiMutation{
-					Script: `(delete! .spec.secretName) false`,
-				},
-			},
-			expected: `{"spec":{}}`,
-		},
-		{
-			name:      "Rudi: local object becomes $localObj",
-			inputData: `{"spec":{"secretName":"foo"}}`,
-			mutation: syncagentv1alpha1.ResourceMutation{
-				Rudi: &syncagentv1alpha1.ResourceRudiMutation{
-					Script: `(set! .spec $localObj.local)`,
-				},
-			},
-			ctx: &TemplateMutationContext{
-				LocalObject: map[string]any{
-					"local": "data",
-				},
-			},
-			expected: `{"spec":"data"}`,
-		},
-		{
-			name:      "Rudi: remote object becomes $remoteObj",
-			inputData: `{"spec":{"secretName":"foo"}}`,
-			mutation: syncagentv1alpha1.ResourceMutation{
-				Rudi: &syncagentv1alpha1.ResourceRudiMutation{
-					Script: `(set! .spec $remoteObj.remote)`,
-				},
-			},
-			ctx: &TemplateMutationContext{
-				RemoteObject: map[string]any{
-					"remote": "data",
-				},
-			},
-			expected: `{"spec":"data"}`,
-		},
 	}
 
 	for _, testcase := range testcases {

internal/sync/syncer_related.go

@@ -150,7 +150,7 @@ func (s *ResourceSyncer) processRelatedResource(log *zap.SugaredLogger, stateSto
 		// sure we can clean up properly
 		blockSourceDeletion: relRes.Origin == "kcp",
 		// apply mutation rules configured for the related resource
-		mutator: mutation.NewMutator(nil), // relRes.Mutation
+		mutator: mutation.NewMutator(relRes.Mutation),
 	}
 
 	requeue, err = syncer.Sync(log, sourceSide, destSide)

sdk/apis/syncagent/v1alpha1/published_resource.go

@@ -85,9 +85,7 @@ type PublishedResourceSpec struct {
 
 	// Mutation allows to configure "rewrite rules" to modify the objects in both
 	// directions during the synchronization.
-	// This is currently disabled in order not to introduce too much freedom in the MVP
-	// and instead rely on Crossplane or other solutions.
-	// Mutation *ResourceMutationSpec `json:"mutation,omitempty"`
+	Mutation *ResourceMutationSpec `json:"mutation,omitempty"`
 
 	Related []RelatedResourceSpec `json:"related,omitempty"`
 }
@@ -138,16 +136,11 @@ type ResourceMutation struct {
 	// Must use exactly one of these options, never more, never fewer.
 	// TODO: Add validation code for this somewhere.
 
-	Rudi     *ResourceRudiMutation     `json:"rudi,omitempty"`
 	Delete   *ResourceDeleteMutation   `json:"delete,omitempty"`
 	Regex    *ResourceRegexMutation    `json:"regex,omitempty"`
 	Template *ResourceTemplateMutation `json:"template,omitempty"`
 }
 
-type ResourceRudiMutation struct {
-	Script string `json:"script"`
-}
-
 type ResourceDeleteMutation struct {
 	Path string `json:"path"`
 }
@@ -181,9 +174,8 @@ type RelatedResourceSpec struct {
 	Reference RelatedResourceReference `json:"reference"`
 
 	// Mutation configures optional transformation rules for the related resource.
-	// Status mutations are not supported and are ignored.
-	// This is disabled for the same reason the mutations for the main resource are disabled.
-	// Mutation *ResourceMutationSpec `json:"mutation,omitempty"`
+	// Status mutations are only performed when the related resource originates in kcp.
+	Mutation *ResourceMutationSpec `json:"mutation,omitempty"`
 }
 
 type RelatedResourceReference struct {