Able to use project components as golang library

.gitignore

@@ -6,3 +6,4 @@ release/
 .idea
 docker-run-release-cache/
 .vscode/
+/cover.out

cmd/helpers.go

@@ -11,11 +11,6 @@ import (
 	"k8s.io/client-go/util/homedir"
 )
 
-const (
-	helm2TestSuccessHook = "test-success"
-	helm3TestHook        = "test"
-)
-
 var (
 	// DefaultHelmHome to hold default home path of .helm dir
 	DefaultHelmHome = filepath.Join(homedir.HomeDir(), ".helm")

cmd/release.go

@@ -71,7 +71,7 @@ func releaseCmd() *cobra.Command {
 }
 
 func (d *release) differentiateHelm3() error {
-	excludes := []string{helm3TestHook, helm2TestSuccessHook}
+	excludes := []string{manifest.Helm3TestHook, manifest.Helm2TestSuccessHook}
 	if d.includeTests {
 		excludes = []string{}
 	}

cmd/revision.go

@@ -79,7 +79,7 @@ func revisionCmd() *cobra.Command {
 
 func (d *revision) differentiateHelm3() error {
 	namespace := os.Getenv("HELM_NAMESPACE")
-	excludes := []string{helm3TestHook, helm2TestSuccessHook}
+	excludes := []string{manifest.Helm3TestHook, manifest.Helm2TestSuccessHook}
 	if d.includeTests {
 		excludes = []string{}
 	}

cmd/rollback.go

@@ -69,7 +69,7 @@ func rollbackCmd() *cobra.Command {
 
 func (d *rollback) backcastHelm3() error {
 	namespace := os.Getenv("HELM_NAMESPACE")
-	excludes := []string{helm3TestHook, helm2TestSuccessHook}
+	excludes := []string{manifest.Helm3TestHook, manifest.Helm2TestSuccessHook}
 	if d.includeTests {
 		excludes = []string{}
 	}

cmd/upgrade.go

@@ -1,8 +1,6 @@
 package cmd
 
 import (
-	"bytes"
-	"encoding/json"
 	"errors"
 	"fmt"
 	"log"
@@ -11,19 +9,9 @@ import (
 	"strconv"
 	"strings"
 
-	jsonpatch "github.com/evanphx/json-patch/v5"
-	jsoniterator "github.com/json-iterator/go"
 	"github.com/spf13/cobra"
 	"helm.sh/helm/v3/pkg/action"
 	"helm.sh/helm/v3/pkg/cli"
-	"helm.sh/helm/v3/pkg/kube"
-	apiextv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
-	apierrors "k8s.io/apimachinery/pkg/api/errors"
-	"k8s.io/apimachinery/pkg/runtime"
-	"k8s.io/apimachinery/pkg/types"
-	"k8s.io/apimachinery/pkg/util/strategicpatch"
-	"k8s.io/cli-runtime/pkg/resource"
-	"sigs.k8s.io/yaml"
 
 	"github.com/databus23/helm-diff/v3/diff"
 	"github.com/databus23/helm-diff/v3/manifest"
@@ -117,7 +105,6 @@ perform.
 `
 
 var envSettings = cli.New()
-var yamlSeperator = []byte("\n---\n")
 
 func newChartCommand() *cobra.Command {
 	diff := diffCmd{
@@ -308,15 +295,7 @@ func (d *diffCmd) runHelm3() error {
 		if err := actionConfig.KubeClient.IsReachable(); err != nil {
 			return err
 		}
-		original, err := actionConfig.KubeClient.Build(bytes.NewBuffer(releaseManifest), false)
-		if err != nil {
-			return fmt.Errorf("unable to build kubernetes objects from original release manifest: %w", err)
-		}
-		target, err := actionConfig.KubeClient.Build(bytes.NewBuffer(installManifest), false)
-		if err != nil {
-			return fmt.Errorf("unable to build kubernetes objects from new release manifest: %w", err)
-		}
-		releaseManifest, installManifest, err = genManifest(original, target)
+		releaseManifest, installManifest, err = manifest.Generate(actionConfig, releaseManifest, installManifest)
 		if err != nil {
 			return fmt.Errorf("unable to generate manifests: %w", err)
 		}
@@ -334,14 +313,14 @@ func (d *diffCmd) runHelm3() error {
 		if d.includeTests {
 			currentSpecs = manifest.Parse(string(releaseManifest), d.namespace, d.normalizeManifests)
 		} else {
-			currentSpecs = manifest.Parse(string(releaseManifest), d.namespace, d.normalizeManifests, helm3TestHook, helm2TestSuccessHook)
+			currentSpecs = manifest.Parse(string(releaseManifest), d.namespace, d.normalizeManifests, manifest.Helm3TestHook, manifest.Helm2TestSuccessHook)
 		}
 	}
 	var newSpecs map[string]*manifest.MappingResult
 	if d.includeTests {
 		newSpecs = manifest.Parse(string(installManifest), d.namespace, d.normalizeManifests)
 	} else {
-		newSpecs = manifest.Parse(string(installManifest), d.namespace, d.normalizeManifests, helm3TestHook, helm2TestSuccessHook)
+		newSpecs = manifest.Parse(string(installManifest), d.namespace, d.normalizeManifests, manifest.Helm3TestHook, manifest.Helm2TestSuccessHook)
 	}
 	seenAnyChanges := diff.Manifests(currentSpecs, newSpecs, &d.Options, os.Stdout)
 
@@ -354,216 +333,3 @@ func (d *diffCmd) runHelm3() error {
 
 	return nil
 }
-
-func genManifest(original, target kube.ResourceList) ([]byte, []byte, error) {
-	var err error
-	releaseManifest, installManifest := make([]byte, 0), make([]byte, 0)
-
-	// to be deleted
-	targetResources := make(map[string]bool)
-	for _, r := range target {
-		targetResources[objectKey(r)] = true
-	}
-	for _, r := range original {
-		if !targetResources[objectKey(r)] {
-			out, _ := yaml.Marshal(r.Object)
-			releaseManifest = append(releaseManifest, yamlSeperator...)
-			releaseManifest = append(releaseManifest, out...)
-		}
-	}
-
-	existingResources := make(map[string]bool)
-	for _, r := range original {
-		existingResources[objectKey(r)] = true
-	}
-
-	var toBeCreated kube.ResourceList
-	for _, r := range target {
-		if !existingResources[objectKey(r)] {
-			toBeCreated = append(toBeCreated, r)
-		}
-	}
-
-	toBeUpdated, err := existingResourceConflict(toBeCreated)
-	if err != nil {
-		return nil, nil, fmt.Errorf("rendered manifests contain a resource that already exists. Unable to continue with update: %w", err)
-	}
-
-	_ = toBeUpdated.Visit(func(r *resource.Info, err error) error {
-		if err != nil {
-			return err
-		}
-		original.Append(r)
-		return nil
-	})
-
-	err = target.Visit(func(info *resource.Info, err error) error {
-		if err != nil {
-			return err
-		}
-		kind := info.Mapping.GroupVersionKind.Kind
-
-		// Fetch the current object for the three way merge
-		helper := resource.NewHelper(info.Client, info.Mapping)
-		currentObj, err := helper.Get(info.Namespace, info.Name)
-		if err != nil {
-			if !apierrors.IsNotFound(err) {
-				return fmt.Errorf("could not get information about the resource: %w", err)
-			}
-			// to be created
-			out, _ := yaml.Marshal(info.Object)
-			installManifest = append(installManifest, yamlSeperator...)
-			installManifest = append(installManifest, out...)
-			return nil
-		}
-		// to be updated
-		out, _ := jsoniterator.ConfigCompatibleWithStandardLibrary.Marshal(currentObj)
-		pruneObj, err := deleteStatusAndTidyMetadata(out)
-		if err != nil {
-			return fmt.Errorf("prune current obj %q with kind %s: %w", info.Name, kind, err)
-		}
-		pruneOut, err := yaml.Marshal(pruneObj)
-		if err != nil {
-			return fmt.Errorf("prune current out %q with kind %s: %w", info.Name, kind, err)
-		}
-		releaseManifest = append(releaseManifest, yamlSeperator...)
-		releaseManifest = append(releaseManifest, pruneOut...)
-
-		originalInfo := original.Get(info)
-		if originalInfo == nil {
-			return fmt.Errorf("could not find %q", info.Name)
-		}
-
-		patch, patchType, err := createPatch(originalInfo.Object, currentObj, info)
-		if err != nil {
-			return err
-		}
-
-		helper.ServerDryRun = true
-		targetObj, err := helper.Patch(info.Namespace, info.Name, patchType, patch, nil)
-		if err != nil {
-			return fmt.Errorf("cannot patch %q with kind %s: %w", info.Name, kind, err)
-		}
-		out, _ = jsoniterator.ConfigCompatibleWithStandardLibrary.Marshal(targetObj)
-		pruneObj, err = deleteStatusAndTidyMetadata(out)
-		if err != nil {
-			return fmt.Errorf("prune current obj %q with kind %s: %w", info.Name, kind, err)
-		}
-		pruneOut, err = yaml.Marshal(pruneObj)
-		if err != nil {
-			return fmt.Errorf("prune current out %q with kind %s: %w", info.Name, kind, err)
-		}
-		installManifest = append(installManifest, yamlSeperator...)
-		installManifest = append(installManifest, pruneOut...)
-		return nil
-	})
-
-	return releaseManifest, installManifest, err
-}
-
-func createPatch(originalObj, currentObj runtime.Object, target *resource.Info) ([]byte, types.PatchType, error) {
-	oldData, err := json.Marshal(originalObj)
-	if err != nil {
-		return nil, types.StrategicMergePatchType, fmt.Errorf("serializing current configuration: %w", err)
-	}
-	newData, err := json.Marshal(target.Object)
-	if err != nil {
-		return nil, types.StrategicMergePatchType, fmt.Errorf("serializing target configuration: %w", err)
-	}
-
-	// Even if currentObj is nil (because it was not found), it will marshal just fine
-	currentData, err := json.Marshal(currentObj)
-	if err != nil {
-		return nil, types.StrategicMergePatchType, fmt.Errorf("serializing live configuration: %w", err)
-	}
-	// kind := target.Mapping.GroupVersionKind.Kind
-	// if kind == "Deployment" {
-	// 	curr, _ := yaml.Marshal(currentObj)
-	// 	fmt.Println(string(curr))
-	// }
-
-	// Get a versioned object
-	versionedObject := kube.AsVersioned(target)
-
-	// Unstructured objects, such as CRDs, may not have an not registered error
-	// returned from ConvertToVersion. Anything that's unstructured should
-	// use the jsonpatch.CreateMergePatch. Strategic Merge Patch is not supported
-	// on objects like CRDs.
-	_, isUnstructured := versionedObject.(runtime.Unstructured)
-
-	// On newer K8s versions, CRDs aren't unstructured but has this dedicated type
-	_, isCRD := versionedObject.(*apiextv1.CustomResourceDefinition)
-
-	if isUnstructured || isCRD {
-		// fall back to generic JSON merge patch
-		patch, err := jsonpatch.CreateMergePatch(oldData, newData)
-		return patch, types.MergePatchType, err
-	}
-
-	patchMeta, err := strategicpatch.NewPatchMetaFromStruct(versionedObject)
-	if err != nil {
-		return nil, types.StrategicMergePatchType, fmt.Errorf("unable to create patch metadata from object: %w", err)
-	}
-
-	patch, err := strategicpatch.CreateThreeWayMergePatch(oldData, newData, currentData, patchMeta, true)
-	return patch, types.StrategicMergePatchType, err
-}
-
-func objectKey(r *resource.Info) string {
-	gvk := r.Object.GetObjectKind().GroupVersionKind()
-	return fmt.Sprintf("%s/%s/%s/%s", gvk.GroupVersion().String(), gvk.Kind, r.Namespace, r.Name)
-}
-
-func existingResourceConflict(resources kube.ResourceList) (kube.ResourceList, error) {
-	var requireUpdate kube.ResourceList
-
-	err := resources.Visit(func(info *resource.Info, err error) error {
-		if err != nil {
-			return err
-		}
-
-		helper := resource.NewHelper(info.Client, info.Mapping)
-		_, err = helper.Get(info.Namespace, info.Name)
-		if err != nil {
-			if apierrors.IsNotFound(err) {
-				return nil
-			}
-			return fmt.Errorf("could not get information about the resource: %w", err)
-		}
-
-		requireUpdate.Append(info)
-		return nil
-	})
-
-	return requireUpdate, err
-}
-
-func deleteStatusAndTidyMetadata(obj []byte) (map[string]interface{}, error) {
-	var objectMap map[string]interface{}
-	err := jsoniterator.Unmarshal(obj, &objectMap)
-	if err != nil {
-		return nil, fmt.Errorf("could not unmarshal byte sequence: %w", err)
-	}
-
-	delete(objectMap, "status")
-
-	metadata := objectMap["metadata"].(map[string]interface{})
-
-	delete(metadata, "managedFields")
-	delete(metadata, "generation")
-
-	// See the below for the goal of this metadata tidy logic.
-	// https://github.com/databus23/helm-diff/issues/326#issuecomment-1008253274
-	if a := metadata["annotations"]; a != nil {
-		annotations := a.(map[string]interface{})
-		delete(annotations, "meta.helm.sh/release-name")
-		delete(annotations, "meta.helm.sh/release-namespace")
-		delete(annotations, "deployment.kubernetes.io/revision")
-
-		if len(annotations) == 0 {
-			delete(metadata, "annotations")
-		}
-	}
-
-	return objectMap, nil
-}