Merge pull request #1447 from isometry/feature/ignore-missing-values-files

Add `.spec.ignoreMissingValuesFiles` to HelmChart API

Makefile

@@ -188,7 +188,7 @@ TMP_DIR=$$(mktemp -d) ;\
 cd $$TMP_DIR ;\
 go mod init tmp ;\
 echo "Downloading $(2)" ;\
-env -i bash -c "GOBIN=$(GOBIN) PATH=$(PATH) GOPATH=$(shell go env GOPATH) GOCACHE=$(shell go env GOCACHE) go install $(2)" ;\
+env -i bash -c "GOBIN=$(GOBIN) PATH=\"$(PATH)\" GOPATH=$(shell go env GOPATH) GOCACHE=$(shell go env GOCACHE) go install $(2)" ;\
 rm -rf $$TMP_DIR ;\
 }
 endef

api/v1beta2/helmchart_types.go

@@ -79,6 +79,11 @@ type HelmChartSpec struct {
 	// +deprecated
 	ValuesFile string `json:"valuesFile,omitempty"`
 
+	// IgnoreMissingValuesFiles controls whether to silently ignore missing values
+	// files rather than failing.
+	// +optional
+	IgnoreMissingValuesFiles bool `json:"ignoreMissingValuesFiles,omitempty"`
+
 	// Suspend tells the controller to suspend the reconciliation of this
 	// source.
 	// +optional
@@ -142,6 +147,12 @@ type HelmChartStatus struct {
 	// +optional
 	ObservedChartName string `json:"observedChartName,omitempty"`
 
+	// ObservedValuesFiles are the observed value files of the last successful
+	// reconciliation.
+	// It matches the chart in the last successfully reconciled artifact.
+	// +optional
+	ObservedValuesFiles []string `json:"observedValuesFiles,omitempty"`
+
 	// Conditions holds the conditions for the HelmChart.
 	// +optional
 	Conditions []metav1.Condition `json:"conditions,omitempty"`

api/v1beta2/zz_generated.deepcopy.go

@@ -484,6 +484,11 @@ func (in *HelmChartSpec) DeepCopy() *HelmChartSpec {
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *HelmChartStatus) DeepCopyInto(out *HelmChartStatus) {
 	*out = *in
+	if in.ObservedValuesFiles != nil {
+		in, out := &in.ObservedValuesFiles, &out.ObservedValuesFiles
+		*out = make([]string, len(*in))
+		copy(*out, *in)
+	}
 	if in.Conditions != nil {
 		in, out := &in.Conditions, &out.Conditions
 		*out = make([]v1.Condition, len(*in))

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

@@ -363,6 +363,11 @@ spec:
                   Chart is the name or path the Helm chart is available at in the
                   SourceRef.
                 type: string
+              ignoreMissingValuesFiles:
+                description: |-
+                  IgnoreMissingValuesFiles controls whether to silently ignore missing values
+                  files rather than failing.
+                type: boolean
               interval:
                 description: |-
                   Interval at which the HelmChart SourceRef is checked for updates.
@@ -638,6 +643,14 @@ spec:
                   ObservedSourceArtifactRevision is the last observed Artifact.Revision
                   of the HelmChartSpec.SourceRef.
                 type: string
+              observedValuesFiles:
+                description: |-
+                  ObservedValuesFiles are the observed value files of the last successful
+                  reconciliation.
+                  It matches the chart in the last successfully reconciled artifact.
+                items:
+                  type: string
+                type: array
               url:
                 description: |-
                   URL is the dynamic fetch link for the latest Artifact.

docs/api/v1beta2/source.md

@@ -660,6 +660,19 @@ is merged before the ValuesFiles items. Ignored when omitted.</p>
 </tr>
 <tr>
 <td>
+<code>ignoreMissingValuesFiles</code><br>
+<em>
+bool
+</em>
+</td>
+<td>
+<em>(Optional)</em>
+<p>IgnoreMissingValuesFiles controls whether to silently ignore missing values
+files rather than failing.</p>
+</td>
+</tr>
+<tr>
+<td>
 <code>suspend</code><br>
 <em>
 bool
@@ -2329,6 +2342,19 @@ is merged before the ValuesFiles items. Ignored when omitted.</p>
 </tr>
 <tr>
 <td>
+<code>ignoreMissingValuesFiles</code><br>
+<em>
+bool
+</em>
+</td>
+<td>
+<em>(Optional)</em>
+<p>IgnoreMissingValuesFiles controls whether to silently ignore missing values
+files rather than failing.</p>
+</td>
+</tr>
+<tr>
+<td>
 <code>suspend</code><br>
 <em>
 bool
@@ -2436,6 +2462,20 @@ resolved chart reference.</p>
 </tr>
 <tr>
 <td>
+<code>observedValuesFiles</code><br>
+<em>
+[]string
+</em>
+</td>
+<td>
+<em>(Optional)</em>
+<p>ObservedValuesFiles are the observed value files of the last successful
+reconciliation.
+It matches the chart in the last successfully reconciled artifact.</p>
+</td>
+</tr>
+<tr>
+<td>
 <code>conditions</code><br>
 <em>
 <a href="https://pkg.go.dev/k8s.io/apimachinery/pkg/apis/meta/v1#Condition">

docs/spec/v1beta2/helmcharts.md

@@ -202,6 +202,16 @@ spec:
 Values files also affect the generated artifact revision, see
 [artifact](#artifact).
 
+### Ignore missing values files
+
+`.spec.ignoreMissingValuesFiles` is an optional field to specify whether missing
+values files should be ignored rather than be considered errors.  It defaults to
+`false`.
+
+When `.spec.valuesFiles` and  `.spec.ignoreMissingValuesFiles` are specified,
+the `.status.observedValuesFiles` field is populated with the list of values
+files that were found and actually contributed to the packaged chart.
+
 ### Reconcile strategy
 
 `.spec.reconcileStrategy` is an optional field to specify what enables the

internal/controller/helmchart_controller.go

@@ -665,8 +665,9 @@ func (r *HelmChartReconciler) buildFromHelmRepository(ctx context.Context, obj *
 	// Construct the chart builder with scoped configuration
 	cb := chart.NewRemoteBuilder(chartRepo)
 	opts := chart.BuildOptions{
-		ValuesFiles: obj.GetValuesFiles(),
+		ValuesFiles:              obj.GetValuesFiles(),
-		Force:       obj.Generation != obj.Status.ObservedGeneration,
+		IgnoreMissingValuesFiles: obj.Spec.IgnoreMissingValuesFiles,
+		Force:                    obj.Generation != obj.Status.ObservedGeneration,
 		// The remote builder will not attempt to download the chart if
 		// an artifact exists with the same name and version and `Force` is false.
 		// It will however try to verify the chart if `obj.Spec.Verify` is set, at every reconciliation.
@@ -674,6 +675,7 @@ func (r *HelmChartReconciler) buildFromHelmRepository(ctx context.Context, obj *
 	}
 	if artifact := obj.GetArtifact(); artifact != nil {
 		opts.CachedChart = r.Storage.LocalPath(*artifact)
+		opts.CachedChartValuesFiles = obj.Status.ObservedValuesFiles
 	}
 
 	// Set the VersionMetadata to the object's Generation if ValuesFiles is defined
@@ -760,11 +762,13 @@ func (r *HelmChartReconciler) buildFromTarballArtifact(ctx context.Context, obj
 
 	// Configure builder options, including any previously cached chart
 	opts := chart.BuildOptions{
-		ValuesFiles: obj.GetValuesFiles(),
+		ValuesFiles:              obj.GetValuesFiles(),
-		Force:       obj.Generation != obj.Status.ObservedGeneration,
+		IgnoreMissingValuesFiles: obj.Spec.IgnoreMissingValuesFiles,
+		Force:                    obj.Generation != obj.Status.ObservedGeneration,
 	}
-	if artifact := obj.Status.Artifact; artifact != nil {
+	if artifact := obj.GetArtifact(); artifact != nil {
 		opts.CachedChart = r.Storage.LocalPath(*artifact)
+		opts.CachedChartValuesFiles = obj.Status.ObservedValuesFiles
 	}
 
 	// Configure revision metadata for chart build if we should react to revision changes
@@ -884,6 +888,11 @@ func (r *HelmChartReconciler) reconcileArtifact(ctx context.Context, _ *patch.Se
 	// Record it on the object
 	obj.Status.Artifact = artifact.DeepCopy()
 	obj.Status.ObservedChartName = b.Name
+	if obj.Spec.IgnoreMissingValuesFiles {
+		obj.Status.ObservedValuesFiles = b.ValuesFiles
+	} else {
+		obj.Status.ObservedValuesFiles = nil
+	}
 
 	// Update symlink on a "best effort" basis
 	symURL, err := r.Storage.Symlink(artifact, "latest.tar.gz")

internal/controller/helmchart_controller_test.go

@@ -927,6 +927,23 @@ func TestHelmChartReconciler_buildFromHelmRepository(t *testing.T) {
 				g.Expect(build.Path).To(BeARegularFile())
 			},
 		},
+		{
+			name: "Uses artifact as build cache with observedValuesFiles",
+			beforeFunc: func(obj *helmv1.HelmChart, repository *helmv1.HelmRepository) {
+				obj.Spec.Chart = chartName
+				obj.Spec.Version = chartVersion
+				obj.Status.Artifact = &sourcev1.Artifact{Path: chartName + "-" + chartVersion + ".tgz"}
+				obj.Status.ObservedValuesFiles = []string{"values.yaml", "override.yaml"}
+			},
+			want: sreconcile.ResultSuccess,
+			assertFunc: func(g *WithT, obj *helmv1.HelmChart, build chart.Build) {
+				g.Expect(build.Name).To(Equal(chartName))
+				g.Expect(build.Version).To(Equal(chartVersion))
+				g.Expect(build.Path).To(Equal(filepath.Join(serverFactory.Root(), obj.Status.Artifact.Path)))
+				g.Expect(build.Path).To(BeARegularFile())
+				g.Expect(build.ValuesFiles).To(Equal([]string{"values.yaml", "override.yaml"}))
+			},
+		},
 		{
 			name: "Sets Generation as VersionMetadata with values files",
 			beforeFunc: func(obj *helmv1.HelmChart, repository *helmv1.HelmRepository) {
@@ -940,6 +957,51 @@ func TestHelmChartReconciler_buildFromHelmRepository(t *testing.T) {
 				g.Expect(build.Version).To(Equal(higherChartVersion + "+3"))
 				g.Expect(build.Path).ToNot(BeEmpty())
 				g.Expect(build.Path).To(BeARegularFile())
+				g.Expect(build.ValuesFiles).To(Equal([]string{"values.yaml", "override.yaml"}))
+			},
+			cleanFunc: func(g *WithT, build *chart.Build) {
+				g.Expect(os.Remove(build.Path)).To(Succeed())
+			},
+		},
+		{
+			name: "Missing values files are an error",
+			beforeFunc: func(obj *helmv1.HelmChart, repository *helmv1.HelmRepository) {
+				obj.Spec.Chart = chartName
+				obj.Spec.ValuesFiles = []string{"missing.yaml"}
+			},
+			wantErr: &chart.BuildError{Err: errors.New("values files merge error: failed to merge chart values: no values file found at path 'missing.yaml'")},
+		},
+		{
+			name: "All missing values files ignored",
+			beforeFunc: func(obj *helmv1.HelmChart, repository *helmv1.HelmRepository) {
+				obj.Spec.Chart = chartName
+				obj.Spec.Version = chartVersion
+				obj.Spec.ValuesFiles = []string{"missing.yaml"}
+				obj.Spec.IgnoreMissingValuesFiles = true
+			},
+			want: sreconcile.ResultSuccess,
+			assertFunc: func(g *WithT, obj *helmv1.HelmChart, build chart.Build) {
+				g.Expect(build.Name).To(Equal(chartName))
+				g.Expect(build.Version).To(Equal(chartVersion + "+0"))
+				g.Expect(build.ValuesFiles).To(BeEmpty())
+			},
+			cleanFunc: func(g *WithT, build *chart.Build) {
+				g.Expect(os.Remove(build.Path)).To(Succeed())
+			},
+		},
+		{
+			name: "Partial missing values files ignored",
+			beforeFunc: func(obj *helmv1.HelmChart, repository *helmv1.HelmRepository) {
+				obj.Spec.Chart = chartName
+				obj.Spec.Version = chartVersion
+				obj.Spec.ValuesFiles = []string{"values.yaml", "override.yaml", "invalid.yaml"}
+				obj.Spec.IgnoreMissingValuesFiles = true
+			},
+			want: sreconcile.ResultSuccess,
+			assertFunc: func(g *WithT, obj *helmv1.HelmChart, build chart.Build) {
+				g.Expect(build.Name).To(Equal(chartName))
+				g.Expect(build.Version).To(Equal(chartVersion + "+0"))
+				g.Expect(build.ValuesFiles).To(Equal([]string{"values.yaml", "override.yaml"}))
 			},
 			cleanFunc: func(g *WithT, build *chart.Build) {
 				g.Expect(os.Remove(build.Path)).To(Succeed())
@@ -1211,6 +1273,7 @@ func TestHelmChartReconciler_buildFromOCIHelmRepository(t *testing.T) {
 				g.Expect(build.Version).To(Equal(metadata.Version))
 				g.Expect(build.Path).To(Equal(storage.LocalPath(*cachedArtifact.DeepCopy())))
 				g.Expect(build.Path).To(BeARegularFile())
+				g.Expect(build.ValuesFiles).To(BeEmpty())
 			},
 		},
 		{
@@ -1433,6 +1496,10 @@ func TestHelmChartReconciler_buildFromTarballArtifact(t *testing.T) {
 				g.Expect(build.Version).To(Equal("0.1.0+3"))
 				g.Expect(build.ResolvedDependencies).To(Equal(0))
 				g.Expect(build.Path).To(BeARegularFile())
+				g.Expect(build.ValuesFiles).To(Equal([]string{
+					"testdata/charts/helmchart/values.yaml",
+					"testdata/charts/helmchart/override.yaml",
+				}))
 			},
 			cleanFunc: func(g *WithT, build *chart.Build) {
 				g.Expect(os.Remove(build.Path)).To(Succeed())
@@ -1451,6 +1518,24 @@ func TestHelmChartReconciler_buildFromTarballArtifact(t *testing.T) {
 				g.Expect(build.Version).To(Equal("0.1.0"))
 				g.Expect(build.Path).To(Equal(storage.LocalPath(*cachedArtifact.DeepCopy())))
 				g.Expect(build.Path).To(BeARegularFile())
+				g.Expect(build.ValuesFiles).To(BeEmpty())
+			},
+		},
+		{
+			name:   "Chart from storage cache with ObservedValuesFiles",
+			source: *chartsArtifact.DeepCopy(),
+			beforeFunc: func(obj *helmv1.HelmChart) {
+				obj.Spec.Chart = "testdata/charts/helmchart-0.1.0.tgz"
+				obj.Status.Artifact = cachedArtifact.DeepCopy()
+				obj.Status.ObservedValuesFiles = []string{"values.yaml", "override.yaml"}
+			},
+			want: sreconcile.ResultSuccess,
+			assertFunc: func(g *WithT, build chart.Build) {
+				g.Expect(build.Name).To(Equal("helmchart"))
+				g.Expect(build.Version).To(Equal("0.1.0"))
+				g.Expect(build.Path).To(Equal(storage.LocalPath(*cachedArtifact.DeepCopy())))
+				g.Expect(build.Path).To(BeARegularFile())
+				g.Expect(build.ValuesFiles).To(Equal([]string{"values.yaml", "override.yaml"}))
 			},
 		},
 		{
@@ -1468,6 +1553,7 @@ func TestHelmChartReconciler_buildFromTarballArtifact(t *testing.T) {
 				g.Expect(build.Version).To(Equal("0.1.0"))
 				g.Expect(build.Path).ToNot(Equal(storage.LocalPath(*cachedArtifact.DeepCopy())))
 				g.Expect(build.Path).To(BeARegularFile())
+				g.Expect(build.ValuesFiles).To(BeEmpty())
 			},
 			cleanFunc: func(g *WithT, build *chart.Build) {
 				g.Expect(os.Remove(build.Path)).To(Succeed())
@@ -1565,7 +1651,7 @@ func TestHelmChartReconciler_reconcileArtifact(t *testing.T) {
 		},
 		{
 			name:  "Copying artifact to storage from build makes ArtifactInStorage=True",
-			build: mockChartBuild("helmchart", "0.1.0", "testdata/charts/helmchart-0.1.0.tgz"),
+			build: mockChartBuild("helmchart", "0.1.0", "testdata/charts/helmchart-0.1.0.tgz", nil),
 			beforeFunc: func(obj *helmv1.HelmChart) {
 				conditions.MarkTrue(obj, sourcev1.ArtifactOutdatedCondition, "Foo", "")
 			},
@@ -1575,6 +1661,7 @@ func TestHelmChartReconciler_reconcileArtifact(t *testing.T) {
 				t.Expect(obj.GetArtifact().Revision).To(Equal("0.1.0"))
 				t.Expect(obj.Status.URL).ToNot(BeEmpty())
 				t.Expect(obj.Status.ObservedChartName).To(Equal("helmchart"))
+				t.Expect(obj.Status.ObservedValuesFiles).To(BeNil())
 			},
 			want: sreconcile.ResultSuccess,
 			assertConditions: []metav1.Condition{
@@ -1597,6 +1684,7 @@ func TestHelmChartReconciler_reconcileArtifact(t *testing.T) {
 			afterFunc: func(t *WithT, obj *helmv1.HelmChart) {
 				t.Expect(obj.Status.Artifact.Path).To(Equal("testdata/charts/helmchart-0.1.0.tgz"))
 				t.Expect(obj.Status.ObservedChartName).To(BeEmpty())
+				t.Expect(obj.Status.ObservedValuesFiles).To(BeNil())
 				t.Expect(obj.Status.URL).To(BeEmpty())
 			},
 		},
@@ -1626,7 +1714,7 @@ func TestHelmChartReconciler_reconcileArtifact(t *testing.T) {
 		},
 		{
 			name:  "Removes ArtifactOutdatedCondition after creating new artifact",
-			build: mockChartBuild("helmchart", "0.1.0", "testdata/charts/helmchart-0.1.0.tgz"),
+			build: mockChartBuild("helmchart", "0.1.0", "testdata/charts/helmchart-0.1.0.tgz", nil),
 			beforeFunc: func(obj *helmv1.HelmChart) {
 				conditions.MarkTrue(obj, sourcev1.ArtifactOutdatedCondition, "Foo", "")
 			},
@@ -1636,6 +1724,7 @@ func TestHelmChartReconciler_reconcileArtifact(t *testing.T) {
 				t.Expect(obj.GetArtifact().Revision).To(Equal("0.1.0"))
 				t.Expect(obj.Status.URL).ToNot(BeEmpty())
 				t.Expect(obj.Status.ObservedChartName).To(Equal("helmchart"))
+				t.Expect(obj.Status.ObservedValuesFiles).To(BeNil())
 			},
 			want: sreconcile.ResultSuccess,
 			assertConditions: []metav1.Condition{
@@ -1644,7 +1733,7 @@ func TestHelmChartReconciler_reconcileArtifact(t *testing.T) {
 		},
 		{
 			name:  "Creates latest symlink to the created artifact",
-			build: mockChartBuild("helmchart", "0.1.0", "testdata/charts/helmchart-0.1.0.tgz"),
+			build: mockChartBuild("helmchart", "0.1.0", "testdata/charts/helmchart-0.1.0.tgz", nil),
 			afterFunc: func(t *WithT, obj *helmv1.HelmChart) {
 				t.Expect(obj.GetArtifact()).ToNot(BeNil())
 
@@ -1659,6 +1748,46 @@ func TestHelmChartReconciler_reconcileArtifact(t *testing.T) {
 				*conditions.TrueCondition(sourcev1.ArtifactInStorageCondition, helmv1.ChartPullSucceededReason, "pulled 'helmchart' chart with version '0.1.0'"),
 			},
 		},
+		{
+			name:  "Updates ObservedValuesFiles after creating new artifact",
+			build: mockChartBuild("helmchart", "0.1.0", "testdata/charts/helmchart-0.1.0.tgz", []string{"values.yaml", "override.yaml"}),
+			beforeFunc: func(obj *helmv1.HelmChart) {
+				conditions.MarkTrue(obj, sourcev1.ArtifactOutdatedCondition, "Foo", "")
+			},
+			afterFunc: func(t *WithT, obj *helmv1.HelmChart) {
+				t.Expect(obj.GetArtifact()).ToNot(BeNil())
+				t.Expect(obj.GetArtifact().Digest).To(Equal("sha256:bbdf96023c912c393b49d5238e227576ed0d20d1bb145d7476d817b80e20c11a"))
+				t.Expect(obj.GetArtifact().Revision).To(Equal("0.1.0"))
+				t.Expect(obj.Status.URL).ToNot(BeEmpty())
+				t.Expect(obj.Status.ObservedChartName).To(Equal("helmchart"))
+				t.Expect(obj.Status.ObservedValuesFiles).To(BeNil())
+			},
+			want: sreconcile.ResultSuccess,
+			assertConditions: []metav1.Condition{
+				*conditions.TrueCondition(sourcev1.ArtifactInStorageCondition, helmv1.ChartPullSucceededReason, "pulled 'helmchart' chart with version '0.1.0'"),
+			},
+		},
+		{
+			name:  "Updates ObservedValuesFiles with IgnoreMissingValuesFiles after creating new artifact",
+			build: mockChartBuild("helmchart", "0.1.0", "testdata/charts/helmchart-0.1.0.tgz", []string{"values.yaml", "override.yaml"}),
+			beforeFunc: func(obj *helmv1.HelmChart) {
+				conditions.MarkTrue(obj, sourcev1.ArtifactOutdatedCondition, "Foo", "")
+				obj.Spec.ValuesFiles = []string{"values.yaml", "missing.yaml", "override.yaml"}
+				obj.Spec.IgnoreMissingValuesFiles = true
+			},
+			afterFunc: func(t *WithT, obj *helmv1.HelmChart) {
+				t.Expect(obj.GetArtifact()).ToNot(BeNil())
+				t.Expect(obj.GetArtifact().Digest).To(Equal("sha256:bbdf96023c912c393b49d5238e227576ed0d20d1bb145d7476d817b80e20c11a"))
+				t.Expect(obj.GetArtifact().Revision).To(Equal("0.1.0"))
+				t.Expect(obj.Status.URL).ToNot(BeEmpty())
+				t.Expect(obj.Status.ObservedChartName).To(Equal("helmchart"))
+				t.Expect(obj.Status.ObservedValuesFiles).To(Equal([]string{"values.yaml", "override.yaml"}))
+			},
+			want: sreconcile.ResultSuccess,
+			assertConditions: []metav1.Condition{
+				*conditions.TrueCondition(sourcev1.ArtifactInStorageCondition, helmv1.ChartPullSucceededReason, "pulled 'helmchart' chart with version '0.1.0'"),
+			},
+		},
 	}
 
 	for _, tt := range tests {
@@ -2016,7 +2145,7 @@ func TestHelmChartReconciler_reconcileSubRecs(t *testing.T) {
 	}
 }
 
-func mockChartBuild(name, version, path string) *chart.Build {
+func mockChartBuild(name, version, path string, valuesFiles []string) *chart.Build {
 	var copyP string
 	if path != "" {
 		f, err := os.Open(path)
@@ -2032,9 +2161,10 @@ func mockChartBuild(name, version, path string) *chart.Build {
 		}
 	}
 	return &chart.Build{
-		Name:    name,
+		Name:        name,
-		Version: version,
+		Version:     version,
-		Path:    copyP,
+		Path:        copyP,
+		ValuesFiles: valuesFiles,
 	}
 }
 

internal/helm/chart/builder.go

@@ -107,6 +107,12 @@ type BuildOptions struct {
 	// ValuesFiles can be set to a list of relative paths, used to compose
 	// and overwrite an alternative default "values.yaml" for the chart.
 	ValuesFiles []string
+	// CachedChartValuesFiles is a list of relative paths that were used to
+	// build the cached chart.
+	CachedChartValuesFiles []string
+	// IgnoreMissingValuesFiles controls whether to silently ignore missing
+	// values files rather than failing.
+	IgnoreMissingValuesFiles bool
 	// CachedChart can be set to the absolute path of a chart stored on
 	// the local filesystem, and is used for simple validation by metadata
 	// comparisons.

internal/helm/chart/builder_local.go

@@ -121,6 +121,11 @@ func (b *localChartBuilder) Build(ctx context.Context, ref Reference, p string,
 				if result.Name == curMeta.Name && result.Version == curMeta.Version {
 					result.Path = opts.CachedChart
 					result.ValuesFiles = opts.GetValuesFiles()
+					if opts.CachedChartValuesFiles != nil {
+						// If the cached chart values files are set, we should use them
+						// instead of reporting the values files.
+						result.ValuesFiles = opts.CachedChartValuesFiles
+					}
 					result.Packaged = requiresPackaging
 
 					return result, nil
@@ -140,9 +145,12 @@ func (b *localChartBuilder) Build(ctx context.Context, ref Reference, p string,
 	}
 
 	// Merge chart values, if instructed
-	var mergedValues map[string]interface{}
+	var (
+		mergedValues map[string]interface{}
+		valuesFiles  []string
+	)
 	if len(opts.GetValuesFiles()) > 0 {
-		if mergedValues, err = mergeFileValues(localRef.WorkDir, opts.ValuesFiles); err != nil {
+		if mergedValues, valuesFiles, err = mergeFileValues(localRef.WorkDir, opts.ValuesFiles, opts.IgnoreMissingValuesFiles); err != nil {
 			return result, &BuildError{Reason: ErrValuesFilesMerge, Err: err}
 		}
 	}
@@ -163,7 +171,7 @@ func (b *localChartBuilder) Build(ctx context.Context, ref Reference, p string,
 		if err != nil {
 			return result, &BuildError{Reason: ErrValuesFilesMerge, Err: err}
 		}
-		result.ValuesFiles = opts.GetValuesFiles()
+		result.ValuesFiles = valuesFiles
 	}
 
 	// Ensure dependencies are fetched if building from a directory
@@ -187,31 +195,42 @@ func (b *localChartBuilder) Build(ctx context.Context, ref Reference, p string,
 }
 
 // mergeFileValues merges the given value file paths into a single "values.yaml" map.
-// The provided (relative) paths may not traverse outside baseDir. It returns the merge
+// The provided (relative) paths may not traverse outside baseDir. By default, a missing
-// result, or an error.
+// file is considered an error. If ignoreMissing is true, missing files are ignored.
-func mergeFileValues(baseDir string, paths []string) (map[string]interface{}, error) {
+// It returns the merge result and the list of files that contributed to that result,
+// or an error.
+func mergeFileValues(baseDir string, paths []string, ignoreMissing bool) (map[string]interface{}, []string, error) {
 	mergedValues := make(map[string]interface{})
+	valuesFiles := make([]string, 0, len(paths))
 	for _, p := range paths {
 		secureP, err := securejoin.SecureJoin(baseDir, p)
 		if err != nil {
-			return nil, err
+			return nil, nil, err
 		}
-		if f, err := os.Stat(secureP); err != nil || !f.Mode().IsRegular() {
+		f, err := os.Stat(secureP)
-			return nil, fmt.Errorf("no values file found at path '%s' (reference '%s')",
+		switch {
+		case err != nil:
+			if ignoreMissing && os.IsNotExist(err) {
+				continue
+			}
+			fallthrough
+		case !f.Mode().IsRegular():
+			return nil, nil, fmt.Errorf("no values file found at path '%s' (reference '%s')",
 				strings.TrimPrefix(secureP, baseDir), p)
 		}
 		b, err := os.ReadFile(secureP)
 		if err != nil {
-			return nil, fmt.Errorf("could not read values from file '%s': %w", p, err)
+			return nil, nil, fmt.Errorf("could not read values from file '%s': %w", p, err)
 		}
 		values := make(map[string]interface{})
 		err = yaml.Unmarshal(b, &values)
 		if err != nil {
-			return nil, fmt.Errorf("unmarshaling values from '%s' failed: %w", p, err)
+			return nil, nil, fmt.Errorf("unmarshaling values from '%s' failed: %w", p, err)
 		}
 		mergedValues = transform.MergeMaps(mergedValues, values)
+		valuesFiles = append(valuesFiles, p)
 	}
-	return mergedValues, nil
+	return mergedValues, valuesFiles, nil
 }
 
 // copyFileToPath attempts to copy in to out. It returns an error if out already exists.

internal/helm/chart/builder_local_test.go

@@ -281,11 +281,13 @@ func TestLocalBuilder_Build_CachedChart(t *testing.T) {
 
 func Test_mergeFileValues(t *testing.T) {
 	tests := []struct {
-		name    string
+		name          string
-		files   []*helmchart.File
+		files         []*helmchart.File
-		paths   []string
+		paths         []string
-		want    map[string]interface{}
+		ignoreMissing bool
-		wantErr string
+		wantValues    map[string]interface{}
+		wantFiles     []string
+		wantErr       string
 	}{
 		{
 			name: "merges values from files",
@@ -295,10 +297,11 @@ func Test_mergeFileValues(t *testing.T) {
 				{Name: "c.yaml", Data: []byte("b: d")},
 			},
 			paths: []string{"a.yaml", "b.yaml", "c.yaml"},
-			want: map[string]interface{}{
+			wantValues: map[string]interface{}{
 				"a": "b",
 				"b": "d",
 			},
+			wantFiles: []string{"a.yaml", "b.yaml", "c.yaml"},
 		},
 		{
 			name:    "illegal traverse",
@@ -318,6 +321,25 @@ func Test_mergeFileValues(t *testing.T) {
 			paths:   []string{"a.yaml"},
 			wantErr: "no values file found at path '/a.yaml'",
 		},
+		{
+			name: "ignore missing files",
+			files: []*helmchart.File{
+				{Name: "a.yaml", Data: []byte("a: b")},
+			},
+			paths:         []string{"a.yaml", "b.yaml"},
+			ignoreMissing: true,
+			wantValues: map[string]interface{}{
+				"a": "b",
+			},
+			wantFiles: []string{"a.yaml"},
+		},
+		{
+			name:          "all files missing",
+			paths:         []string{"a.yaml"},
+			ignoreMissing: true,
+			wantValues:    map[string]interface{}{},
+			wantFiles:     []string{},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -329,16 +351,18 @@ func Test_mergeFileValues(t *testing.T) {
 				g.Expect(os.WriteFile(filepath.Join(baseDir, f.Name), f.Data, 0o640)).To(Succeed())
 			}
 
-			got, err := mergeFileValues(baseDir, tt.paths)
+			gotValues, gotFiles, err := mergeFileValues(baseDir, tt.paths, tt.ignoreMissing)
 			if tt.wantErr != "" {
 				g.Expect(err).To(HaveOccurred())
 				g.Expect(err.Error()).To(ContainSubstring(tt.wantErr))
-				g.Expect(got).To(BeNil())
+				g.Expect(gotValues).To(BeNil())
+				g.Expect(gotFiles).To(BeNil())
 				return
 			}
 
 			g.Expect(err).ToNot(HaveOccurred())
-			g.Expect(got).To(Equal(tt.want))
+			g.Expect(gotValues).To(Equal(tt.wantValues))
+			g.Expect(gotFiles).To(Equal(tt.wantFiles))
 		})
 	}
 }

internal/helm/chart/builder_remote.go

@@ -103,7 +103,7 @@ func (b *remoteChartBuilder) Build(ctx context.Context, ref Reference, p string,
 	}
 	chart.Metadata.Version = result.Version
 
-	mergedValues, err := mergeChartValues(chart, opts.ValuesFiles)
+	mergedValues, valuesFiles, err := mergeChartValues(chart, opts.ValuesFiles, opts.IgnoreMissingValuesFiles)
 	if err != nil {
 		err = fmt.Errorf("failed to merge chart values: %w", err)
 		return result, &BuildError{Reason: ErrValuesFilesMerge, Err: err}
@@ -113,7 +113,7 @@ func (b *remoteChartBuilder) Build(ctx context.Context, ref Reference, p string,
 		if err != nil {
 			return nil, &BuildError{Reason: ErrValuesFilesMerge, Err: err}
 		}
-		result.ValuesFiles = opts.GetValuesFiles()
+		result.ValuesFiles = valuesFiles
 	}
 
 	// Package the chart with the custom values
@@ -203,6 +203,11 @@ func generateBuildResult(cv *repo.ChartVersion, opts BuildOptions) (*Build, bool
 				if result.Name == curMeta.Name && result.Version == curMeta.Version {
 					result.Path = opts.CachedChart
 					result.ValuesFiles = opts.GetValuesFiles()
+					if opts.CachedChartValuesFiles != nil {
+						// If the cached chart values files are set, we should use them
+						// instead of reporting the values files.
+						result.ValuesFiles = opts.CachedChartValuesFiles
+					}
 					result.Packaged = requiresPackaging
 					return result, true, nil
 				}
@@ -226,13 +231,18 @@ func setBuildMetaData(version, versionMetadata string) (*semver.Version, error)
 }
 
 // mergeChartValues merges the given chart.Chart Files paths into a single "values.yaml" map.
-// It returns the merge result, or an error.
+// By default, a missing file is considered an error. If ignoreMissing is set true,
-func mergeChartValues(chart *helmchart.Chart, paths []string) (map[string]interface{}, error) {
+// missing files are ignored.
+// It returns the merge result and the list of files that contributed to that result,
+// or an error.
+func mergeChartValues(chart *helmchart.Chart, paths []string, ignoreMissing bool) (map[string]interface{}, []string, error) {
 	mergedValues := make(map[string]interface{})
+	valuesFiles := make([]string, 0, len(paths))
 	for _, p := range paths {
 		cfn := filepath.Clean(p)
 		if cfn == chartutil.ValuesfileName {
 			mergedValues = transform.MergeMaps(mergedValues, chart.Values)
+			valuesFiles = append(valuesFiles, p)
 			continue
 		}
 		var b []byte
@@ -243,15 +253,19 @@ func mergeChartValues(chart *helmchart.Chart, paths []string) (map[string]interf
 			}
 		}
 		if b == nil {
-			return nil, fmt.Errorf("no values file found at path '%s'", p)
+			if ignoreMissing {
+				continue
+			}
+			return nil, nil, fmt.Errorf("no values file found at path '%s'", p)
 		}
 		values := make(map[string]interface{})
 		if err := yaml.Unmarshal(b, &values); err != nil {
-			return nil, fmt.Errorf("unmarshaling values from '%s' failed: %w", p, err)
+			return nil, nil, fmt.Errorf("unmarshaling values from '%s' failed: %w", p, err)
 		}
 		mergedValues = transform.MergeMaps(mergedValues, values)
+		valuesFiles = append(valuesFiles, p)
 	}
-	return mergedValues, nil
+	return mergedValues, valuesFiles, nil
 }
 
 // validatePackageAndWriteToPath atomically writes the packaged chart from reader

internal/helm/chart/builder_remote_test.go

@@ -443,11 +443,13 @@ entries:
 
 func Test_mergeChartValues(t *testing.T) {
 	tests := []struct {
-		name    string
+		name          string
-		chart   *helmchart.Chart
+		chart         *helmchart.Chart
-		paths   []string
+		paths         []string
-		want    map[string]interface{}
+		ignoreMissing bool
-		wantErr string
+		wantValues    map[string]interface{}
+		wantFiles     []string
+		wantErr       string
 	}{
 		{
 			name: "merges values",
@@ -459,10 +461,11 @@ func Test_mergeChartValues(t *testing.T) {
 				},
 			},
 			paths: []string{"a.yaml", "b.yaml", "c.yaml"},
-			want: map[string]interface{}{
+			wantValues: map[string]interface{}{
 				"a": "b",
 				"b": "d",
 			},
+			wantFiles: []string{"a.yaml", "b.yaml", "c.yaml"},
 		},
 		{
 			name: "uses chart values",
@@ -475,10 +478,11 @@ func Test_mergeChartValues(t *testing.T) {
 				},
 			},
 			paths: []string{chartutil.ValuesfileName, "c.yaml"},
-			want: map[string]interface{}{
+			wantValues: map[string]interface{}{
 				"a": "b",
 				"b": "d",
 			},
+			wantFiles: []string{chartutil.ValuesfileName, "c.yaml"},
 		},
 		{
 			name: "unmarshal error",
@@ -496,21 +500,59 @@ func Test_mergeChartValues(t *testing.T) {
 			paths:   []string{"a.yaml"},
 			wantErr: "no values file found at path 'a.yaml'",
 		},
+		{
+			name: "merges values ignoring file missing",
+			chart: &helmchart.Chart{
+				Files: []*helmchart.File{
+					{Name: "a.yaml", Data: []byte("a: b")},
+				},
+			},
+			paths:         []string{"a.yaml", "b.yaml"},
+			ignoreMissing: true,
+			wantValues: map[string]interface{}{
+				"a": "b",
+			},
+			wantFiles: []string{"a.yaml"},
+		},
+		{
+			name:          "merges values ignoring all missing",
+			chart:         &helmchart.Chart{},
+			paths:         []string{"a.yaml"},
+			ignoreMissing: true,
+			wantValues:    map[string]interface{}{},
+			wantFiles:     []string{},
+		},
+		{
+			name: "uses chart values ignoring missing file",
+			chart: &helmchart.Chart{
+				Values: map[string]interface{}{
+					"a": "b",
+				},
+			},
+			paths:         []string{chartutil.ValuesfileName, "c.yaml"},
+			ignoreMissing: true,
+			wantValues: map[string]interface{}{
+				"a": "b",
+			},
+			wantFiles: []string{chartutil.ValuesfileName},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			g := NewWithT(t)
 
-			got, err := mergeChartValues(tt.chart, tt.paths)
+			gotValues, gotFiles, err := mergeChartValues(tt.chart, tt.paths, tt.ignoreMissing)
 			if tt.wantErr != "" {
 				g.Expect(err).To(HaveOccurred())
 				g.Expect(err.Error()).To(ContainSubstring(tt.wantErr))
-				g.Expect(got).To(BeNil())
+				g.Expect(gotValues).To(BeNil())
+				g.Expect(gotFiles).To(BeNil())
 				return
 			}
 
 			g.Expect(err).ToNot(HaveOccurred())
-			g.Expect(got).To(Equal(tt.want))
+			g.Expect(gotValues).To(Equal(tt.wantValues))
+			g.Expect(gotFiles).To(Equal(tt.wantFiles))
 		})
 	}
 }