feat(helm): add local path support for deps in requirements.yaml

fix change requests

Author: qwangqw

docs/helm/helm_dependency.md

@@ -39,6 +39,16 @@ appending '/index.yaml' to the URL, it should be able to retrieve the chart
 repository's index. Note: 'repository' cannot be a repository alias. It must be
 a URL.
 
+Starting from 2.2.0, repository can be defined as the path to the directory of
+the dependency charts stored locally. The path should start with a prefix of "file://".
+For example,
+    # requirements.yaml
+    dependencies:
+	- name: nginx
+	  version: "1.2.3"
+	  repository: "file://../depedency_chart/nginx"
+If the dependency chart is retrieved locally, it is not required to have the repository
+added to helm by "helm add repo". Version matching is also supported for this case.
 
 ### Options inherited from parent commands
 

pkg/downloader/manager.go

@@ -313,13 +313,13 @@ func (m *Manager) getRepoNames(deps []*chartutil.Dependency) (map[string]string,
 	for _, dd := range deps {
 		// if dep chart is from local path, verify the path is valid
 		if strings.HasPrefix(dd.Repository, "file://") {
-			depPath, err := filepath.Abs(dd.Repository[7:])
+			depPath, err := filepath.Abs(strings.TrimPrefix(dd.Repository, "file://"))
 			if err != nil {
 				return nil, err
 			}
 
 			if _, err = os.Stat(depPath); os.IsNotExist(err) {
-				return nil, fmt.Errorf("directory %s not found: %s", depPath, err)
+				return nil, fmt.Errorf("directory %s not found", depPath)
 			}
 
 			fmt.Fprintf(m.Out, "Repository from local path: %s\n", dd.Repository)

pkg/resolver/resolver.go

@@ -58,7 +58,7 @@ func (r *Resolver) Resolve(reqs *chartutil.Requirements, repoNames map[string]st
 	missing := []string{}
 	for i, d := range reqs.Dependencies {
 		if strings.HasPrefix(d.Repository, "file://") {
-			depPath, err := filepath.Abs(d.Repository[7:])
+			depPath, err := filepath.Abs(strings.TrimPrefix(d.Repository, "file://"))
 			if err != nil {
 				return nil, err
 			}

pkg/resolver/resolver_test.go

@@ -78,7 +78,20 @@ func TestResolve(t *testing.T) {
 			},
 		},
 		{
-			name: "repo from local invalid path",
+			name: "repo from valid local path",
+			req: &chartutil.Requirements{
+				Dependencies: []*chartutil.Dependency{
+					{Name: "signtest", Repository: "file://../testdata/testcharts/signtest", Version: "0.1.0"},
+				},
+			},
+			expect: &chartutil.RequirementsLock{
+				Dependencies: []*chartutil.Dependency{
+					{Name: "signtest", Repository: "file://../testdata/testcharts/signtest", Version: "0.1.0"},
+				},
+			},
+		},
+		{
+			name: "repo from invalid local path",
 			req: &chartutil.Requirements{
 				Dependencies: []*chartutil.Dependency{
 					{Name: "notexist", Repository: "file://../testdata/notexist", Version: "0.1.0"},