Add ReconcileStrategy to HelmChart

This commit adds a `ReconcileStrategy` field to the `HelmChart` resource, which
allows defining when a new chart should be packaged and/or published if it
originates from a `Bucket` or `GitRepository` resource.

The two available strategies are:

- `ChartVersion`: creates a new artifact when the version of the Helm chart as
  defined in the `Chart.yaml` from the Source is different from the current
  version.
- `Revision`: creates a new artifact when the revision of the Source is
  different from the current revision.

For the `Revision` strategy, the (checksum part of the) revision of the
artifact the chart originatesfrom is added as SemVer metadata.

A chart from a `GitRepository` with Artifact revision
`main/f0faacd5164a875ebdbd9e3fab778f49c5aadbbc` and a chart with e.g. SemVer
`0.1.0` will be published as `0.1.0+f0faacd5164a875ebdbd9e3fab778f49c5aadbbc`.

A chart from a `Bucket` with Artifact revision
`f0faacd5164a875ebdbd9e3fab778f49c5aadbbc` and a chart with e.g. SemVer `0.1.0`
will be published as `0.1.0+f0faacd5164a875ebdbd9e3fab778f49c5aadbbc`.

Signed-off-by: Dylan Arbour <arbourd@users.noreply.github.com>

api/v1beta1/helmchart_types.go

@@ -45,6 +45,15 @@ type HelmChartSpec struct {
 	// +required
 	Interval metav1.Duration `json:"interval"`
 
+	// Determines what enables the creation of a new artifact. Valid values are
+	// ('ChartVersion', 'Revision').
+	// See the documentation of the values for an explanation on their behavior.
+	// Defaults to ChartVersion when omitted.
+	// +kubebuilder:validation:Enum=ChartVersion;Revision
+	// +kubebuilder:default:=ChartVersion
+	// +optional
+	ReconcileStrategy string `json:"reconcileStrategy,omitempty"`
+
 	// Alternative list of values files to use as the chart values (values.yaml
 	// is not included by default), expected to be a relative path in the SourceRef.
 	// Values files are merged in the order of this list with the last file overriding
@@ -65,6 +74,14 @@ type HelmChartSpec struct {
 	Suspend bool `json:"suspend,omitempty"`
 }
 
+const (
+	// ReconcileStrategyChartVersion reconciles when the version of the Helm chart is different.
+	ReconcileStrategyChartVersion string = "ChartVersion"
+
+	// ReconcileStrategyRevision reconciles when the Revision of the source is different.
+	ReconcileStrategyRevision string = "Revision"
+)
+
 // LocalHelmChartSourceReference contains enough information to let you locate
 // the typed referenced object at namespace level.
 type LocalHelmChartSourceReference struct {

config/crd/bases/source.toolkit.fluxcd.io_helmcharts.yaml

@@ -62,6 +62,13 @@ spec:
               interval:
                 description: The interval at which to check the Source for updates.
                 type: string
+              reconcileStrategy:
+                default: ChartVersion
+                description: Determines what enables the creation of a new artifact. Valid values are ('ChartVersion', 'Revision'). See the documentation of the values for an explanation on their behavior. Defaults to ChartVersion when omitted.
+                enum:
+                - ChartVersion
+                - Revision
+                type: string
               sourceRef:
                 description: The reference to the Source the chart is available at.
                 properties:

controllers/helmchart_controller.go

@@ -27,6 +27,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/Masterminds/semver/v3"
 	securejoin "github.com/cyphar/filepath-securejoin"
 	"github.com/go-logr/logr"
 	helmchart "helm.sh/helm/v3/pkg/chart"
@@ -526,9 +527,29 @@ func (r *HelmChartReconciler) reconcileFromTarballArtifact(ctx context.Context,
 		return sourcev1.HelmChartNotReady(chart, sourcev1.StorageOperationFailedReason, err.Error()), err
 	}
 
+	v, err := semver.NewVersion(helmChart.Metadata.Version)
+	if err != nil {
+		err = fmt.Errorf("semver error: %w", err)
+		return sourcev1.HelmChartNotReady(chart, sourcev1.StorageOperationFailedReason, err.Error()), err
+	}
+
+	version := v.String()
+	if chart.Spec.ReconcileStrategy == sourcev1.ReconcileStrategyRevision {
+		// Isolate the commit SHA from GitRepository type artifacts by removing the branch/ prefix.
+		splitRev := strings.Split(artifact.Revision, "/")
+		v, err := v.SetMetadata(splitRev[len(splitRev)-1])
+		if err != nil {
+			err = fmt.Errorf("semver error: %w", err)
+			return sourcev1.HelmChartNotReady(chart, sourcev1.StorageOperationFailedReason, err.Error()), err
+		}
+
+		version = v.String()
+		helmChart.Metadata.Version = v.String()
+	}
+
 	// Return early if the revision is still the same as the current chart artifact
-	newArtifact := r.Storage.NewArtifactFor(chart.Kind, chart.ObjectMeta.GetObjectMeta(), helmChart.Metadata.Version,
+	newArtifact := r.Storage.NewArtifactFor(chart.Kind, chart.ObjectMeta.GetObjectMeta(), version,
-		fmt.Sprintf("%s-%s.tgz", helmChart.Metadata.Name, helmChart.Metadata.Version))
+		fmt.Sprintf("%s-%s.tgz", helmChart.Metadata.Name, version))
 	if !force && apimeta.IsStatusConditionTrue(chart.Status.Conditions, meta.ReadyCondition) && chart.GetArtifact().HasRevision(newArtifact.Revision) {
 		if newArtifact.URL != artifact.URL {
 			r.Storage.SetArtifactURL(chart.GetArtifact())

controllers/helmchart_controller_test.go

@@ -709,7 +709,7 @@ var _ = Describe("HelmChartReconciler", func() {
 			err = f.Close()
 			Expect(err).NotTo(HaveOccurred())
 
-			_, err = wt.Commit("Chart version bump", &git.CommitOptions{
+			commit, err := wt.Commit("Chart version bump", &git.CommitOptions{
 				Author: &object.Signature{
 					Name:  "John Doe",
 					Email: "john@example.com",
@@ -735,6 +735,21 @@ var _ = Describe("HelmChartReconciler", func() {
 			Expect(helmChart.Values["testDefault"]).To(BeTrue())
 			Expect(helmChart.Values["testOverride"]).To(BeFalse())
 
+			When("Setting reconcileStrategy to Revision", func() {
+				updated := &sourcev1.HelmChart{}
+				Expect(k8sClient.Get(context.Background(), key, updated)).To(Succeed())
+				updated.Spec.ReconcileStrategy = sourcev1.ReconcileStrategyRevision
+				Expect(k8sClient.Update(context.Background(), updated)).To(Succeed())
+				got := &sourcev1.HelmChart{}
+				Eventually(func() bool {
+					_ = k8sClient.Get(context.Background(), key, got)
+					return got.Status.Artifact.Revision != updated.Status.Artifact.Revision &&
+						storage.ArtifactExist(*got.Status.Artifact)
+				}, timeout, interval).Should(BeTrue())
+				Expect(got.Status.Artifact.Revision).To(ContainSubstring(updated.Status.Artifact.Revision))
+				Expect(got.Status.Artifact.Revision).To(ContainSubstring(commit.String()))
+			})
+
 			When("Setting valid valuesFiles attribute", func() {
 				updated := &sourcev1.HelmChart{}
 				Expect(k8sClient.Get(context.Background(), key, updated)).To(Succeed())

docs/api/source.md

@@ -555,6 +555,21 @@ Kubernetes meta/v1.Duration
 </tr>
 <tr>
 <td>
+<code>reconcileStrategy</code><br>
+<em>
+string
+</em>
+</td>
+<td>
+<em>(Optional)</em>
+<p>Determines what enables reconciliation. Valid values are (&lsquo;ChartVersion&rsquo;,
+&lsquo;Revision&rsquo;). See the documentation of the values for an explanation on their
+behavior.
+Defaults to ChartVersion when omitted.</p>
+</td>
+</tr>
+<tr>
+<td>
 <code>valuesFiles</code><br>
 <em>
 []string
@@ -1613,6 +1628,21 @@ Kubernetes meta/v1.Duration
 </tr>
 <tr>
 <td>
+<code>reconcileStrategy</code><br>
+<em>
+string
+</em>
+</td>
+<td>
+<em>(Optional)</em>
+<p>Determines what enables reconciliation. Valid values are (&lsquo;ChartVersion&rsquo;,
+&lsquo;Revision&rsquo;). See the documentation of the values for an explanation on their
+behavior.
+Defaults to ChartVersion when omitted.</p>
+</td>
+</tr>
+<tr>
+<td>
 <code>valuesFiles</code><br>
 <em>
 []string

docs/spec/v1beta1/helmcharts.md

@@ -28,6 +28,15 @@ type HelmChartSpec struct {
 	// +required
 	Interval metav1.Duration `json:"interval"`
 
+	// Determines what enables the creation of a new artifact. Valid values are
+	// ('ChartVersion', 'Revision').
+	// See the documentation of the values for an explanation on their behavior.
+	// Defaults to ChartVersion when omitted.
+	// +kubebuilder:validation:Enum=ChartVersion;Revision
+	// +kubebuilder:default:=ChartVersion
+	// +optional
+	ReconcileStrategy string `json:"reconcileStrategy,omitempty"`
+
 	// Alternative list of values files to use as the chart values (values.yaml
 	// is not included by default), expected to be a relative path in the SourceRef.
 	// Values files are merged in the order of this list with the last file overriding
@@ -49,6 +58,18 @@ type HelmChartSpec struct {
 }
 ```
 
+### Reconciliation strategies
+
+```go
+const (
+	// ReconcileStrategyChartVersion creates a new chart artifact when the version of the Helm chart is different.
+	ReconcileStrategyChartVersion string = "ChartVersion"
+
+	// ReconcileStrategyRevision creates a new chart artifact when the Revision of the SourceRef is different.
+	ReconcileStrategyRevision string = "Revision"
+)
+```
+
 ### Reference types
 
 ```go
@@ -230,6 +251,23 @@ spec:
     - ./charts/podinfo/values-production.yaml
 ```
 
+Reconcile with every change to the source revision:
+
+```yaml
+apiVersion: source.toolkit.fluxcd.io/v1beta1
+kind: HelmChart
+metadata:
+  name: podinfo
+  namespace: default
+spec:
+  chart: ./charts/podinfo
+  sourceRef:
+    name: podinfo
+    kind: GitRepository
+  interval: 10m
+  reconcileStrategy: Revision
+```
+
 ## Status examples
 
 Successful chart pull: