fix(helm): Port accept dependency in requirements.yaml from charts directory (#6611)

* Port #6578 to Helm 3

Signed-off-by: Martin Hickey <martin.hickey@ie.ibm.com>

* Update after reviw

Review comments:
- https://github.com/helm/helm/pull/6611#discussion_r332745703

Signed-off-by: Martin Hickey <martin.hickey@ie.ibm.com>

internal/resolver/resolver.go

@@ -53,6 +53,19 @@ func (r *Resolver) Resolve(reqs []*chart.Dependency, repoNames map[string]string
 	locked := make([]*chart.Dependency, len(reqs))
 	missing := []string{}
 	for i, d := range reqs {
+		if d.Repository == "" {
+			// Local chart subfolder
+			if _, err := GetLocalPath(filepath.Join("charts", d.Name), r.chartpath); err != nil {
+				return nil, err
+			}
+
+			locked[i] = &chart.Dependency{
+				Name:       d.Name,
+				Repository: "",
+				Version:    d.Version,
+			}
+			continue
+		}
 		if strings.HasPrefix(d.Repository, "file://") {
 
 			if _, err := GetLocalPath(d.Repository, r.chartpath); err != nil {

internal/resolver/resolver_test.go

@@ -85,6 +85,29 @@ func TestResolve(t *testing.T) {
 			},
 			err: true,
 		},
+		{
+			name: "repo from valid path under charts path",
+			req: []*chart.Dependency{
+				{Name: "localdependency", Repository: "", Version: "0.1.0"},
+			},
+			expect: &chart.Lock{
+				Dependencies: []*chart.Dependency{
+					{Name: "localdependency", Repository: "", Version: "0.1.0"},
+				},
+			},
+		},
+		{
+			name: "repo from invalid path under charts path",
+			req: []*chart.Dependency{
+				{Name: "nonexistentdependency", Repository: "", Version: "0.1.0"},
+			},
+			expect: &chart.Lock{
+				Dependencies: []*chart.Dependency{
+					{Name: "nonexistentlocaldependency", Repository: "", Version: "0.1.0"},
+				},
+			},
+			err: true,
+		},
 	}
 
 	repoNames := map[string]string{"alpine": "kubernetes-charts", "redis": "kubernetes-charts"}

internal/resolver/testdata/chartpath/charts/localdependency/Chart.yaml

@@ -0,0 +1,3 @@
+description: A Helm chart for Kubernetes
+name: localdependency
+version: 0.1.0

pkg/downloader/manager.go

@@ -203,6 +203,31 @@ func (m *Manager) downloadAll(deps []*chart.Dependency) error {
 	fmt.Fprintf(m.Out, "Saving %d charts\n", len(deps))
 	var saveError error
 	for _, dep := range deps {
+		// No repository means the chart is in charts directory
+		if dep.Repository == "" {
+			fmt.Fprintf(m.Out, "Dependency %s did not declare a repository. Assuming it exists in the charts directory\n", dep.Name)
+			chartPath := filepath.Join(tmpPath, dep.Name)
+			ch, err := loader.LoadDir(chartPath)
+			if err != nil {
+				return fmt.Errorf("Unable to load chart: %v", err)
+			}
+
+			constraint, err := semver.NewConstraint(dep.Version)
+			if err != nil {
+				return fmt.Errorf("Dependency %s has an invalid version/constraint format: %s", dep.Name, err)
+			}
+
+			v, err := semver.NewVersion(ch.Metadata.Version)
+			if err != nil {
+				return fmt.Errorf("Invalid version %s for dependency %s: %s", dep.Version, dep.Name, err)
+			}
+
+			if !constraint.Check(v) {
+				saveError = fmt.Errorf("Dependency %s at version %s does not satisfy the constraint %s", dep.Name, ch.Metadata.Version, dep.Version)
+				break
+			}
+			continue
+		}
 		if strings.HasPrefix(dep.Repository, "file://") {
 			if m.Debug {
 				fmt.Fprintf(m.Out, "Archiving %s from repo %s\n", dep.Name, dep.Repository)
@@ -247,8 +272,11 @@ func (m *Manager) downloadAll(deps []*chart.Dependency) error {
 	if saveError == nil {
 		fmt.Fprintln(m.Out, "Deleting outdated charts")
 		for _, dep := range deps {
-			if err := m.safeDeleteDep(dep.Name, tmpPath); err != nil {
-				return err
+			// Chart from local charts directory stays in place
+			if dep.Repository != "" {
+				if err := m.safeDeleteDep(dep.Name, tmpPath); err != nil {
+					return err
+				}
 			}
 		}
 		if err := move(tmpPath, destPath); err != nil {
@@ -360,6 +388,10 @@ func (m *Manager) getRepoNames(deps []*chart.Dependency) (map[string]string, err
 	// by Helm.
 	missing := []string{}
 	for _, dd := range deps {
+		// Don't map the repository, we don't need to download chart from charts directory
+		if dd.Repository == "" {
+			continue
+		}
 		// if dep chart is from local path, verify the path is valid
 		if strings.HasPrefix(dd.Repository, "file://") {
 			if _, err := resolver.GetLocalPath(dd.Repository, m.ChartPath); err != nil {

pkg/downloader/manager_test.go

@@ -147,6 +147,13 @@ func TestGetRepoNames(t *testing.T) {
 			},
 			expect: map[string]string{"oedipus-rex": "testing"},
 		},
+		{
+			name: "repo from local chart under charts path",
+			req: []*chart.Dependency{
+				{Name: "local-subchart", Repository: ""},
+			},
+			expect: map[string]string{},
+		},
 	}
 
 	for _, tt := range tests {

pkg/downloader/testdata/local-subchart/Chart.yaml

@@ -0,0 +1,3 @@
+description: A Helm chart for Kubernetes
+name: local-subchart
+version: 0.1.0