feat(template) allow linting to be run at template time

refactor lint run to a function

refactor template run to a function

Signed-off-by: Scott Morgan <morgandev@gmail.com>

cmd/helm/lint.go

@@ -48,79 +48,88 @@ func newLintCmd(out io.Writer) *cobra.Command {
 		Use:   "lint PATH",
 		Short: "examines a chart for possible issues",
 		Long:  longLintHelp,
-		RunE: func(cmd *cobra.Command, args []string) error {
-			paths := []string{"."}
-			if len(args) > 0 {
-				paths = args
-			}
-			if client.WithSubcharts {
-				for _, p := range paths {
-					filepath.Walk(filepath.Join(p, "charts"), func(path string, info os.FileInfo, err error) error {
-						if info != nil {
-							if info.Name() == "Chart.yaml" {
-								paths = append(paths, filepath.Dir(path))
-							} else if strings.HasSuffix(path, ".tgz") || strings.HasSuffix(path, ".tar.gz") {
-								paths = append(paths, path)
-							}
-						}
-						return nil
-					})
-				}
-			}
-
-			client.Namespace = settings.Namespace()
-			vals, err := valueOpts.MergeValues(getter.All(settings))
+		RunE: func(_ *cobra.Command, args []string) error {
+			err := runLint(args, client, valueOpts, out)
 			if err != nil {
 				return err
 			}
 
-			var message strings.Builder
-			failed := 0
+			return nil
+		},
+	}
 
-			for _, path := range paths {
-				fmt.Fprintf(&message, "==> Linting %s\n", path)
+	f := cmd.Flags()
+	f.BoolVar(&client.Strict, "strict", false, "fail on lint warnings")
+	f.BoolVar(&client.WithSubcharts, "with-subcharts", false, "lint dependent charts")
+	addValueOptionsFlags(f, valueOpts)
 
-				result := client.Run([]string{path}, vals)
+	return cmd
+}
 
-				// All the Errors that are generated by a chart
-				// that failed a lint will be included in the
-				// results.Messages so we only need to print
-				// the Errors if there are no Messages.
-				if len(result.Messages) == 0 {
-					for _, err := range result.Errors {
-						fmt.Fprintf(&message, "Error %s\n", err)
+func runLint(args []string, client *action.Lint, valueOpts *values.Options, out io.Writer) error {
+	paths := []string{"."}
+	if len(args) > 0 {
+		paths = args
+	}
+	if client.WithSubcharts {
+		for _, p := range paths {
+			filepath.Walk(filepath.Join(p, "charts"), func(path string, info os.FileInfo, err error) error {
+				if info != nil {
+					if info.Name() == "Chart.yaml" {
+						paths = append(paths, filepath.Dir(path))
+					} else if strings.HasSuffix(path, ".tgz") || strings.HasSuffix(path, ".tar.gz") {
+						paths = append(paths, path)
 					}
 				}
+				return nil
+			})
+		}
+	}
 
-				for _, msg := range result.Messages {
-					fmt.Fprintf(&message, "%s\n", msg)
-				}
+	client.Namespace = settings.Namespace()
+	vals, err := valueOpts.MergeValues(getter.All(settings))
+	if err != nil {
+		return err
+	}
 
-				if len(result.Errors) != 0 {
-					failed++
-				}
+	var message strings.Builder
+	failed := 0
 
-				// Adding extra new line here to break up the
-				// results, stops this from being a big wall of
-				// text and makes it easier to follow.
-				fmt.Fprint(&message, "\n")
-			}
+	for _, path := range paths {
+		fmt.Fprintf(&message, "==> Linting %s\n", path)
 
-			fmt.Fprintf(out, message.String())
+		result := client.Run([]string{path}, vals)
 
-			summary := fmt.Sprintf("%d chart(s) linted, %d chart(s) failed", len(paths), failed)
-			if failed > 0 {
-				return errors.New(summary)
+		// All the Errors that are generated by a chart
+		// that failed a lint will be included in the
+		// results.Messages so we only need to print
+		// the Errors if there are no Messages.
+		if len(result.Messages) == 0 {
+			for _, err := range result.Errors {
+				fmt.Fprintf(&message, "Error %s\n", err)
 			}
-			fmt.Fprintln(out, summary)
-			return nil
-		},
+		}
+
+		for _, msg := range result.Messages {
+			fmt.Fprintf(&message, "%s\n", msg)
+		}
+
+		if len(result.Errors) != 0 {
+			failed++
+		}
+
+		// Adding extra new line here to break up the
+		// results, stops this from being a big wall of
+		// text and makes it easier to follow.
+		fmt.Fprint(&message, "\n")
 	}
 
-	f := cmd.Flags()
-	f.BoolVar(&client.Strict, "strict", false, "fail on lint warnings")
-	f.BoolVar(&client.WithSubcharts, "with-subcharts", false, "lint dependent charts")
-	addValueOptionsFlags(f, valueOpts)
+	fmt.Fprintf(out, message.String())
 
-	return cmd
+	summary := fmt.Sprintf("%d chart(s) linted, %d chart(s) failed", len(paths), failed)
+	if failed > 0 {
+		return errors.New(summary)
+	}
+	fmt.Fprintln(out, summary)
+	return nil
 }

cmd/helm/template.go

@@ -43,13 +43,19 @@ faked locally. Additionally, none of the server-side testing of chart validity
 (e.g. whether an API is supported) is done.
 `
 
+type templateOptions struct {
+	extraAPIs   []string
+	showFiles   []string
+	lint        bool
+	includeCrds bool
+	validate    bool
+}
+
 func newTemplateCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
-	var validate bool
-	var includeCrds bool
-	client := action.NewInstall(cfg)
+	o := &templateOptions{}
+	installClient := action.NewInstall(cfg)
+	lintClient := action.NewLint()
 	valueOpts := &values.Options{}
-	var extraAPIs []string
-	var showFiles []string
 
 	cmd := &cobra.Command{
 		Use:   "template [NAME] [CHART]",
@@ -57,61 +63,17 @@ func newTemplateCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 		Long:  templateDesc,
 		Args:  require.MinimumNArgs(1),
 		RunE: func(_ *cobra.Command, args []string) error {
-			client.DryRun = true
-			client.ReleaseName = "RELEASE-NAME"
-			client.Replace = true // Skip the name check
-			client.ClientOnly = !validate
-			client.APIVersions = chartutil.VersionSet(extraAPIs)
-			client.IncludeCRDs = includeCrds
-			rel, err := runInstall(args, client, valueOpts, out)
-			if err != nil {
-				return err
-			}
-
-			var manifests bytes.Buffer
-			fmt.Fprintln(&manifests, strings.TrimSpace(rel.Manifest))
-
-			if !client.DisableHooks {
-				for _, m := range rel.Hooks {
-					fmt.Fprintf(&manifests, "---\n# Source: %s\n%s\n", m.Path, m.Manifest)
+			var err error
+			if o.lint {
+				err := runLint(args, lintClient, valueOpts, out)
+				if err != nil {
+					return err
 				}
 			}
 
-			// if we have a list of files to render, then check that each of the
-			// provided files exists in the chart.
-			if len(showFiles) > 0 {
-				splitManifests := releaseutil.SplitManifests(manifests.String())
-				manifestNameRegex := regexp.MustCompile("# Source: [^/]+/(.+)")
-				var manifestsToRender []string
-				for _, f := range showFiles {
-					missing := true
-					for _, manifest := range splitManifests {
-						submatch := manifestNameRegex.FindStringSubmatch(manifest)
-						if len(submatch) == 0 {
-							continue
-						}
-						manifestName := submatch[1]
-						// manifest.Name is rendered using linux-style filepath separators on Windows as
-						// well as macOS/linux.
-						manifestPathSplit := strings.Split(manifestName, "/")
-						manifestPath := filepath.Join(manifestPathSplit...)
-
-						// if the filepath provided matches a manifest path in the
-						// chart, render that manifest
-						if f == manifestPath {
-							manifestsToRender = append(manifestsToRender, manifest)
-							missing = false
-						}
-					}
-					if missing {
-						return fmt.Errorf("could not find template %s in chart", f)
-					}
-				}
-				for _, m := range manifestsToRender {
-					fmt.Fprintf(out, "---\n%s\n", m)
-				}
-			} else {
-				fmt.Fprintf(out, "%s", manifests.String())
+			err = runTemplate(args, installClient, valueOpts, o, out)
+			if err != nil {
+				return err
 			}
 
 			return nil
@@ -120,19 +82,82 @@ func newTemplateCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 
 	// Function providing dynamic auto-completion
 	completion.RegisterValidArgsFunc(cmd, func(cmd *cobra.Command, args []string, toComplete string) ([]string, completion.BashCompDirective) {
-		return compInstall(args, toComplete, client)
+		return compInstall(args, toComplete, installClient)
 	})
 
 	f := cmd.Flags()
-	addInstallFlags(f, client, valueOpts)
-	f.StringArrayVarP(&showFiles, "show-only", "s", []string{}, "only show manifests rendered from the given templates")
-	f.StringVar(&client.OutputDir, "output-dir", "", "writes the executed templates to files in output-dir instead of stdout")
-	f.BoolVar(&validate, "validate", false, "validate your manifests against the Kubernetes cluster you are currently pointing at. This is the same validation performed on an install")
-	f.BoolVar(&includeCrds, "include-crds", false, "include CRDs in the templated output")
-	f.BoolVar(&client.IsUpgrade, "is-upgrade", false, "set .Release.IsUpgrade instead of .Release.IsInstall")
-	f.StringArrayVarP(&extraAPIs, "api-versions", "a", []string{}, "Kubernetes api versions used for Capabilities.APIVersions")
-	f.BoolVar(&client.UseReleaseName, "release-name", false, "use release name in the output-dir path.")
-	bindPostRenderFlag(cmd, &client.PostRenderer)
+	addInstallFlags(f, installClient, valueOpts)
+	f.StringArrayVarP(&o.showFiles, "show-only", "s", []string{}, "only show manifests rendered from the given templates")
+	f.StringVar(&installClient.OutputDir, "output-dir", "", "writes the executed templates to files in output-dir instead of stdout")
+	f.BoolVar(&installClient.IsUpgrade, "is-upgrade", false, "set .Release.IsUpgrade instead of .Release.IsInstall")
+	f.BoolVar(&o.validate, "validate", false, "validate your manifests against the Kubernetes cluster you are currently pointing at. This is the same validation performed on an install")
+	f.BoolVar(&o.includeCrds, "include-crds", false, "include CRDs in the templated output")
+	f.BoolVar(&o.lint, "lint", false, "examines a chart for possible issues")
+	f.BoolVar(&lintClient.Strict, "strict", false, "fail on lint warnings")
+	f.StringArrayVarP(&o.extraAPIs, "api-versions", "a", []string{}, "Kubernetes api versions used for Capabilities.APIVersions")
+	f.BoolVar(&installClient.UseReleaseName, "release-name", false, "use release name in the output-dir path.")
+	bindPostRenderFlag(cmd, &installClient.PostRenderer)
 
 	return cmd
 }
+
+func runTemplate(args []string, client *action.Install, valueOpts *values.Options, o *templateOptions, out io.Writer) error {
+	client.DryRun = true
+	client.ReleaseName = "RELEASE-NAME"
+	client.Replace = true // Skip the name check
+	client.ClientOnly = !o.validate
+	client.APIVersions = chartutil.VersionSet(o.extraAPIs)
+	client.IncludeCRDs = o.includeCrds
+	rel, err := runInstall(args, client, valueOpts, out)
+	if err != nil {
+		return err
+	}
+
+	var manifests bytes.Buffer
+	fmt.Fprintln(&manifests, strings.TrimSpace(rel.Manifest))
+
+	if !client.DisableHooks {
+		for _, m := range rel.Hooks {
+			fmt.Fprintf(&manifests, "---\n# Source: %s\n%s\n", m.Path, m.Manifest)
+		}
+	}
+
+	// if we have a list of files to render, then check that each of the
+	// provided files exists in the chart.
+	if len(o.showFiles) > 0 {
+		splitManifests := releaseutil.SplitManifests(manifests.String())
+		manifestNameRegex := regexp.MustCompile("# Source: [^/]+/(.+)")
+		var manifestsToRender []string
+		for _, f := range o.showFiles {
+			missing := true
+			for _, manifest := range splitManifests {
+				submatch := manifestNameRegex.FindStringSubmatch(manifest)
+				if len(submatch) == 0 {
+					continue
+				}
+				manifestName := submatch[1]
+				// manifest.Name is rendered using linux-style filepath separators on Windows as
+				// well as macOS/linux.
+				manifestPathSplit := strings.Split(manifestName, "/")
+				manifestPath := filepath.Join(manifestPathSplit...)
+
+				// if the filepath provided matches a manifest path in the
+				// chart, render that manifest
+				if f == manifestPath {
+					manifestsToRender = append(manifestsToRender, manifest)
+					missing = false
+				}
+			}
+			if missing {
+				return fmt.Errorf("could not find template %s in chart", f)
+			}
+		}
+		for _, m := range manifestsToRender {
+			fmt.Fprintf(out, "---\n%s\n", m)
+		}
+	} else {
+		fmt.Fprintf(out, "%s", manifests.String())
+	}
+
+	return nil
+}

cmd/helm/template_test.go

@@ -74,6 +74,23 @@ func TestTemplateCmd(t *testing.T) {
 			cmd:    fmt.Sprintf("template '%s'", "testdata/testcharts/chart-with-template-lib-archive-dep"),
 			golden: "output/template-chart-with-template-lib-archive-dep.txt",
 		},
+		{
+			name:   "check linting success",
+			cmd:    fmt.Sprintf("template '%s' --lint", "testdata/testcharts/empty"),
+			golden: "output/template-linting-success.txt",
+		},
+		{
+			name:      "check linting fail",
+			cmd:       fmt.Sprintf("template '%s' --lint", "testdata/testcharts/novals"),
+			wantError: true,
+			golden:    "output/template-linting-fail.txt",
+		},
+		{
+			name:      "check linting strict fail",
+			cmd:       fmt.Sprintf("template '%s' --lint --strict", "testdata/testcharts/novals"),
+			wantError: true,
+			golden:    "output/template-linting-strict-fail.txt",
+		},
 		{
 			name:   "check kube api versions",
 			cmd:    fmt.Sprintf("template --api-versions helm.k8s.io/test '%s'", chartPath),

cmd/helm/testdata/output/template-linting-fail.txt

@@ -0,0 +1,6 @@
+==> Linting testdata/testcharts/novals
+[INFO] Chart.yaml: icon is recommended
+[INFO] values.yaml: file does not exist
+[ERROR] templates/: template: novals/templates/alpine-pod.yaml:18:33: executing "novals/templates/alpine-pod.yaml" at <.Release.Time.Seconds>: nil pointer evaluating interface {}.Seconds
+
+Error: 1 chart(s) linted, 1 chart(s) failed

cmd/helm/testdata/output/template-linting-strict-fail.txt

@@ -0,0 +1,6 @@
+==> Linting testdata/testcharts/novals
+[INFO] Chart.yaml: icon is recommended
+[INFO] values.yaml: file does not exist
+[ERROR] templates/: template: novals/templates/alpine-pod.yaml:4:36: executing "novals/templates/alpine-pod.yaml" at <.Values.Name>: map has no entry for key "Name"
+
+Error: 1 chart(s) linted, 1 chart(s) failed

cmd/helm/testdata/output/template-linting-success.txt

@@ -0,0 +1,7 @@
+==> Linting testdata/testcharts/empty
+[INFO] Chart.yaml: icon is recommended
+
+1 chart(s) linted, 0 chart(s) failed
+---
+# Source: empty/templates/empty.yaml
+# This file is intentionally blank