Add example converter for conversion of singleton lists to embedded objects

pkg/examples/conversion/example_conversions.go

@@ -0,0 +1,170 @@
+// SPDX-FileCopyrightText: 2024 The Crossplane Authors <https://crossplane.io>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package conversion
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/crossplane/upjet/pkg/config"
+	"github.com/pkg/errors"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	k8sschema "k8s.io/apimachinery/pkg/runtime/schema"
+	kyaml "k8s.io/apimachinery/pkg/util/yaml"
+	"sigs.k8s.io/yaml"
+
+	"github.com/crossplane/upjet/pkg/config/conversion"
+)
+
+func ConvertSingletonListToEmbeddedObject(pc *config.Provider, startPath, licenseHeaderPath string) error {
+	resourceRegistry := prepareResourceRegistry(pc)
+
+	var license string
+	var lErr error
+	if licenseHeaderPath != "" {
+		license, lErr = getLicenseHeader(licenseHeaderPath)
+		if lErr != nil {
+			return errors.Wrap(lErr, "failed to get license header")
+		}
+	}
+
+	err := filepath.Walk(startPath, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return errors.Wrapf(err, "walk failed: %s", startPath)
+		}
+
+		var convertedFileContent string
+		if !info.IsDir() && strings.HasSuffix(info.Name(), ".yaml") {
+			log.Printf("Converting: %s\n", path)
+			content, err := os.ReadFile(filepath.Clean(path))
+			if err != nil {
+				return errors.Wrapf(err, "failed to read the %s file", path)
+			}
+
+			examples, err := decodeExamples(string(content))
+			if err != nil {
+				return errors.Wrap(err, "failed to decode examples")
+			}
+
+			rootResource := resourceRegistry[fmt.Sprintf("%s/%s", examples[0].GroupVersionKind().Kind, examples[0].GroupVersionKind().Group)]
+			if rootResource == nil {
+				log.Printf("Warning: Skipping %s because the corresponding resource could not be found in the provider", path)
+				return nil
+			}
+
+			newPath := strings.ReplaceAll(path, examples[0].GroupVersionKind().Version, rootResource.Version)
+			if path == newPath {
+				return nil
+			}
+			annotationValue := strings.ToLower(fmt.Sprintf("%s/%s/%s", rootResource.ShortGroup, rootResource.Version, rootResource.Kind))
+			for _, e := range examples {
+				if resource, ok := resourceRegistry[fmt.Sprintf("%s/%s", e.GroupVersionKind().Kind, e.GroupVersionKind().Group)]; ok {
+					conversionPaths := resource.CRDListConversionPaths()
+					if conversionPaths != nil && e.GroupVersionKind().Version != resource.Version {
+						for i, cp := range conversionPaths {
+							// Here, for the manifests to be converted, only `forProvider
+							// is converted, assuming the `initProvider` field is empty in the
+							// spec.
+							conversionPaths[i] = "spec.forProvider." + cp
+						}
+						converted, err := conversion.Convert(e.Object, conversionPaths, conversion.ToEmbeddedObject)
+						if err != nil {
+							return errors.Wrap(err, "failed to convert example to embedded object")
+						}
+						e.Object = converted
+						e.SetGroupVersionKind(k8sschema.GroupVersionKind{
+							Group:   e.GroupVersionKind().Group,
+							Version: resource.Version,
+							Kind:    e.GetKind(),
+						})
+					}
+					annotations := e.GetAnnotations()
+					annotations["meta.upbound.io/example-id"] = annotationValue
+					e.SetAnnotations(annotations)
+				}
+			}
+			convertedFileContent = license + "\n\n"
+			if err := writeExampleContent(path, convertedFileContent, examples, newPath); err != nil {
+				return errors.Wrap(err, "failed to write example content")
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		log.Printf("Error walking the path %q: %v\n", startPath, err)
+	}
+	return nil
+}
+
+func writeExampleContent(path string, convertedFileContent string, examples []*unstructured.Unstructured, newPath string) error {
+	for i, e := range examples {
+		var convertedData []byte
+		e := e
+		convertedData, err := yaml.Marshal(&e)
+		if err != nil {
+			return errors.Wrap(err, "failed to marshal example to yaml")
+		}
+		if i == len(examples)-1 {
+			convertedFileContent += string(convertedData)
+		} else {
+			convertedFileContent += string(convertedData) + "\n---\n\n"
+		}
+	}
+	dir := filepath.Dir(newPath)
+
+	// Create all necessary directories if they do not exist
+	if err := os.MkdirAll(dir, os.ModePerm); err != nil {
+		return errors.Wrap(err, "failed to create directory")
+	}
+	f, err := os.Create(filepath.Clean(newPath))
+	if err != nil {
+		return errors.Wrap(err, "failed to create file")
+	}
+	if _, err := f.WriteString(convertedFileContent); err != nil {
+		return errors.Wrap(err, "failed to write to file")
+	}
+	log.Printf("Converted: %s\n", path)
+	return nil
+}
+
+func getLicenseHeader(licensePath string) (string, error) {
+	licenseData, err := os.ReadFile(licensePath)
+	if err != nil {
+		return "", errors.Wrapf(err, "failed to read license file: %s", licensePath)
+	}
+
+	return string(licenseData), nil
+}
+
+func prepareResourceRegistry(pc *config.Provider) map[string]*config.Resource {
+	reg := map[string]*config.Resource{}
+	for _, r := range pc.Resources {
+		reg[fmt.Sprintf("%s/%s.%s", r.Kind, r.ShortGroup, pc.RootGroup)] = r
+	}
+	return reg
+}
+
+func decodeExamples(content string) ([]*unstructured.Unstructured, error) {
+	var manifests []*unstructured.Unstructured
+	decoder := kyaml.NewYAMLOrJSONDecoder(bytes.NewBufferString(content), 1024)
+	for {
+		u := &unstructured.Unstructured{}
+		if err := decoder.Decode(&u); err != nil {
+			if errors.Is(err, io.EOF) {
+				break
+			}
+			return nil, errors.Wrap(err, "cannot decode manifest")
+		}
+		if u != nil {
+			manifests = append(manifests, u)
+		}
+	}
+	return manifests, nil
+}