Add some common utility functions to migration framework

Signed-off-by: Sergen Yalçın <[email protected]>

pkg/migration/converter.go

@@ -15,6 +15,9 @@
 package migration
 
 import (
+	"fmt"
+	"strings"
+
 	"github.com/crossplane/crossplane-runtime/pkg/fieldpath"
 	"github.com/crossplane/crossplane-runtime/pkg/resource"
 	xpv1 "github.com/crossplane/crossplane/apis/apiextensions/v1"
@@ -259,3 +262,69 @@ func toPackageLock(u unstructured.Unstructured) (*xppkgv1beta1.Lock, error) {
 	}
 	return lock, nil
 }
+
+func ConvertComposedTemplateTags(sourceTemplate xpv1.ComposedTemplate, value string, key string) ([]xpv1.Patch, error) {
+	var patchesToAdd []xpv1.Patch
+	for _, p := range sourceTemplate.Patches {
+		if p.ToFieldPath != nil {
+			if strings.HasPrefix(*p.ToFieldPath, "spec.forProvider.tags") {
+				u, err := FromRawExtension(sourceTemplate.Base)
+				if err != nil {
+					return nil, errors.Wrap(err, "failed to convert ComposedTemplate")
+				}
+				paved := fieldpath.Pave(u.Object)
+				key, err := paved.GetString(strings.ReplaceAll(*p.ToFieldPath, value, key))
+				if err != nil {
+					return nil, errors.Wrap(err, "failed to get value from paved")
+				}
+				s := fmt.Sprintf(`spec.forProvider.tags["%s"]`, key)
+				patchesToAdd = append(patchesToAdd, xpv1.Patch{
+					FromFieldPath: p.FromFieldPath,
+					ToFieldPath:   &s,
+					Transforms:    p.Transforms,
+					Policy:        p.Policy,
+				})
+			}
+		}
+	}
+	return patchesToAdd, nil
+}
+
+func ConvertComposedTemplatePatchesMap(sourceTemplate xpv1.ComposedTemplate, conversionMap map[string]string) []xpv1.Patch {
+	var patchesToAdd []xpv1.Patch
+	for _, p := range sourceTemplate.Patches {
+		switch p.Type { // nolint:exhaustive
+		case xpv1.PatchTypeFromCompositeFieldPath, xpv1.PatchTypeCombineFromComposite, "":
+			{
+				if p.ToFieldPath != nil {
+					if to, ok := conversionMap[*p.ToFieldPath]; ok {
+						patchesToAdd = append(patchesToAdd, xpv1.Patch{
+							Type:          p.Type,
+							FromFieldPath: p.FromFieldPath,
+							ToFieldPath:   &to,
+							Transforms:    p.Transforms,
+							Policy:        p.Policy,
+							Combine:       p.Combine,
+						})
+					}
+				}
+			}
+		case xpv1.PatchTypeToCompositeFieldPath, xpv1.PatchTypeCombineToComposite:
+			{
+				if p.FromFieldPath != nil {
+					if to, ok := conversionMap[*p.FromFieldPath]; ok {
+						patchesToAdd = append(patchesToAdd, xpv1.Patch{
+							Type:          p.Type,
+							FromFieldPath: &to,
+							ToFieldPath:   p.ToFieldPath,
+							Transforms:    p.Transforms,
+							Policy:        p.Policy,
+							Combine:       p.Combine,
+						})
+					}
+				}
+			}
+		}
+	}
+	return patchesToAdd
+}

pkg/migration/registry.go

@@ -15,7 +15,9 @@
 package migration
 
 import (
+	"fmt"
 	"regexp"
+	"strings"
 
 	"github.com/crossplane/crossplane-runtime/pkg/resource"
 	xpv1 "github.com/crossplane/crossplane/apis/apiextensions/v1"
@@ -452,6 +454,35 @@ func (d *delegatingConverter) PatchSets(psMap map[string]*xpv1.PatchSet) error {
 	return d.psFn(psMap)
 }
 
+func DefaultPatchSetsConverter(sourcePatchSets map[string]*xpv1.PatchSet) error {
+	tagsPatchSetName := ""
+	for _, patchSet := range sourcePatchSets {
+		for _, patch := range patchSet.Patches {
+			if patch.ToFieldPath != nil {
+				if strings.HasPrefix(*patch.ToFieldPath, "spec.forProvider.tags") {
+					tagsPatchSetName = patchSet.Name
+					break
+				}
+			}
+		}
+		if tagsPatchSetName != "" {
+			break
+		}
+	}
+
+	tPs := sourcePatchSets[tagsPatchSetName]
+	if tPs == nil {
+		return nil
+	}
+	for i, p := range tPs.Patches {
+		r := strings.NewReplacer("metadata.labels[", "", "]", "")
+		key := r.Replace(*p.FromFieldPath)
+		*tPs.Patches[i].ToFieldPath = fmt.Sprintf(`spec.forProvider.tags[%s]`, key)
+	}
+	// convert patch sets in the source
+	return nil
+}
+
 // Resource takes a managed resource and returns zero or more managed
 // resources to be created by calling the configured ResourceConversionFn.
 func (d *delegatingConverter) Resource(mg resource.Managed) ([]resource.Managed, error) {
@@ -471,6 +502,24 @@ func (d *delegatingConverter) ComposedTemplate(sourceTemplate xpv1.ComposedTempl
 	return d.cmpFn(sourceTemplate, convertedTemplates...)
 }
 
+func DefaultCompositionConverter(convertTags bool, conversionMap map[string]string) ComposedTemplateConversionFn {
+	return func(sourceTemplate xpv1.ComposedTemplate, convertedTemplates ...*xpv1.ComposedTemplate) error {
+		var patchesToAdd []xpv1.Patch
+		var err error
+		if convertTags {
+			patchesToAdd, err = ConvertComposedTemplateTags(sourceTemplate, ".value", ".key")
+			if err != nil {
+				return errors.Wrap(err, "failed to convert tags")
+			}
+		}
+		patchesToAdd = append(patchesToAdd, ConvertComposedTemplatePatchesMap(sourceTemplate, conversionMap)...)
+		for i := range convertedTemplates {
+			convertedTemplates[i].Patches = append(convertedTemplates[i].Patches, patchesToAdd...)
+		}
+		return nil
+	}
+}
+
 // RegisterAPIConversionFunctions registers the supplied ResourceConversionFn and
 // ComposedTemplateConversionFn for the specified GVK, and the supplied
 // PatchSetsConversionFn for all the discovered Compositions.