ref(client): add overwrite option

Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>

cmd/helm/upgrade.go

@@ -147,6 +147,7 @@ func newUpgradeCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 	f.BoolVar(&client.Recreate, "recreate-pods", false, "performs pods restart for the resource if applicable")
 	f.MarkDeprecated("recreate-pods", "functionality will no longer be updated. Consult the documentation for other methods to recreate pods")
 	f.BoolVar(&client.Force, "force", false, "force resource updates through a replacement strategy")
+	f.BoolVar(&client.Overwrite, "overwrite", true, "overwrite all outside changes")
 	f.BoolVar(&client.DisableHooks, "no-hooks", false, "disable pre/post upgrade hooks")
 	f.DurationVar(&client.Timeout, "timeout", 300*time.Second, "time to wait for any individual Kubernetes operation (like Jobs for hooks)")
 	f.BoolVar(&client.ResetValues, "reset-values", false, "when upgrading, reset the values to the ones built into the chart")

pkg/action/rollback.go

@@ -159,7 +159,7 @@ func (r *Rollback) performRollback(currentRelease, targetRelease *release.Releas
 		r.cfg.Log("rollback hooks disabled for %s", targetRelease.Name)
 	}
 
-	results, err := r.cfg.KubeClient.Update(current, target, r.Force)
+	results, err := r.cfg.KubeClient.Update(current, target, r.Force, true)
 
 	if err != nil {
 		msg := fmt.Sprintf("Rollback %q failed: %s", targetRelease.Name, err)

pkg/action/upgrade.go

@@ -49,6 +49,7 @@ type Upgrade struct {
 	DisableHooks bool
 	DryRun       bool
 	Force        bool
+	Overwrite    bool
 	ResetValues  bool
 	ReuseValues  bool
 	// Recreate will (if true) recreate pods after a rollback.
@@ -236,7 +237,7 @@ func (u *Upgrade) performUpgrade(originalRelease, upgradedRelease *release.Relea
 		u.cfg.Log("upgrade hooks disabled for %s", upgradedRelease.Name)
 	}
 
-	results, err := u.cfg.KubeClient.Update(current, target, u.Force)
+	results, err := u.cfg.KubeClient.Update(current, target, u.Force, u.Overwrite)
 	if err != nil {
 		u.cfg.recordRelease(originalRelease)
 		return u.failRelease(upgradedRelease, results.Created, err)

pkg/kube/client.go

@@ -31,6 +31,7 @@ import (
 	batch "k8s.io/api/batch/v1"
 	v1 "k8s.io/api/core/v1"
 	apiextv1beta1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1beta1"
+	apiequality "k8s.io/apimachinery/pkg/api/equality"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -142,7 +143,7 @@ func (c *Client) Build(reader io.Reader, validate bool) (ResourceList, error) {
 // occurs, a Result will still be returned with the error, containing all
 // resource updates, creations, and deletions that were attempted. These can be
 // used for cleanup or other logging purposes.
-func (c *Client) Update(original, target ResourceList, force bool) (*Result, error) {
+func (c *Client) Update(original, target ResourceList, force bool, overwrite bool) (*Result, error) {
 	updateErrors := []string{}
 	res := &Result{}
 
@@ -177,7 +178,7 @@ func (c *Client) Update(original, target ResourceList, force bool) (*Result, err
 			return errors.Errorf("no %s with the name %q found", kind, info.Name)
 		}
 
-		if err := updateResource(c, info, originalInfo.Object, force); err != nil {
+		if err := updateResource(c, info, originalInfo.Object, force, overwrite); err != nil {
 			c.Log("error updating the resource %q:\n\t %v", info.Name, err)
 			updateErrors = append(updateErrors, err.Error())
 		}
@@ -323,7 +324,7 @@ func deleteResource(info *resource.Info) error {
 	return err
 }
 
-func createPatch(target *resource.Info, current runtime.Object) ([]byte, types.PatchType, error) {
+func createPatch(target *resource.Info, current runtime.Object, overwrite bool) ([]byte, types.PatchType, error) {
 	oldData, err := json.Marshal(current)
 	if err != nil {
 		return nil, types.StrategicMergePatchType, errors.Wrap(err, "serializing current configuration")
@@ -359,6 +360,19 @@ func createPatch(target *resource.Info, current runtime.Object) ([]byte, types.P
 		return patch, types.MergePatchType, err
 	}
 
+	if !overwrite {
+		// While different objects need different merge types, the parent function
+		// that calls this does not try to create a patch when the data (first
+		// returned object) is nil. We can skip calculating the merge type as
+		// the returned merge type is ignored.
+		if apiequality.Semantic.DeepEqual(oldData, newData) {
+			return nil, types.StrategicMergePatchType, nil
+		}
+
+		patch, err := strategicpatch.CreateTwoWayMergePatch(oldData, newData, versionedObject)
+		return patch, types.StrategicMergePatchType, err
+	}
+
 	patchMeta, err := strategicpatch.NewPatchMetaFromStruct(versionedObject)
 	if err != nil {
 		return nil, types.StrategicMergePatchType, errors.Wrap(err, "unable to create patch metadata from object")
@@ -368,14 +382,14 @@ func createPatch(target *resource.Info, current runtime.Object) ([]byte, types.P
 	return patch, types.StrategicMergePatchType, err
 }
 
-func updateResource(c *Client, target *resource.Info, currentObj runtime.Object, force bool) error {
+func updateResource(c *Client, target *resource.Info, currentObj runtime.Object, force bool, overwrite bool) error {
 	var (
 		obj    runtime.Object
 		helper = resource.NewHelper(target.Client, target.Mapping)
 		kind   = target.Mapping.GroupVersionKind.Kind
 	)
 
-	patch, patchType, err := createPatch(target, currentObj)
+	patch, patchType, err := createPatch(target, currentObj, overwrite)
 	if err != nil {
 		return errors.Wrap(err, "failed to create patch")
 	}

pkg/kube/client_test.go

@@ -162,7 +162,7 @@ func TestUpdate(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if _, err := c.Update(first, second, false); err != nil {
+	if _, err := c.Update(first, second, false, true); err != nil {
 		t.Fatal(err)
 	}
 	// TODO: Find a way to test methods that use Client Set

pkg/kube/fake/fake.go

@@ -75,11 +75,11 @@ func (f *FailingKubeClient) WatchUntilReady(resources kube.ResourceList, d time.
 }
 
 // Update returns the configured error if set or prints
-func (f *FailingKubeClient) Update(r, modified kube.ResourceList, ignoreMe bool) (*kube.Result, error) {
+func (f *FailingKubeClient) Update(r, modified kube.ResourceList, ignoreMe bool, ignoreMeToo bool) (*kube.Result, error) {
 	if f.UpdateError != nil {
 		return &kube.Result{}, f.UpdateError
 	}
-	return f.PrintingKubeClient.Update(r, modified, ignoreMe)
+	return f.PrintingKubeClient.Update(r, modified, ignoreMe, ignoreMeToo)
 }
 
 // Build returns the configured error if set or prints

pkg/kube/fake/printer.go

@@ -70,7 +70,7 @@ func (p *PrintingKubeClient) WatchUntilReady(resources kube.ResourceList, _ time
 }
 
 // Update implements KubeClient Update.
-func (p *PrintingKubeClient) Update(_, modified kube.ResourceList, _ bool) (*kube.Result, error) {
+func (p *PrintingKubeClient) Update(_, modified kube.ResourceList, _ bool, _ bool) (*kube.Result, error) {
 	_, err := io.Copy(p.Out, bufferize(modified))
 	if err != nil {
 		return nil, err

pkg/kube/interface.go

@@ -45,7 +45,7 @@ type Interface interface {
 
 	// Update updates one or more resources or creates the resource
 	// if it doesn't exist.
-	Update(original, target ResourceList, force bool) (*Result, error)
+	Update(original, target ResourceList, force bool, overwrite bool) (*Result, error)
 
 	// Build creates a resource list from a Reader
 	//