support helm 3 using exec

- uses 'helm template' for update
- uses 'helm get' to retrieve releases and revisions

Author: jonasrutishauser

cmd/helm3.go

@@ -0,0 +1,98 @@
+package cmd
+
+import (
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"strconv"
+)
+
+func getRelease(release, namespace string) ([]byte, error) {
+	args := []string{"get", "manifest", release}
+	if namespace != "" {
+		args = append(args, "--namespace", namespace)
+	}
+	cmd := exec.Command(os.Getenv("HELM_BIN"), args...)
+	return cmd.Output()
+}
+
+func getHooks(release, namespace string) ([]byte, error) {
+	args := []string{"get", "hooks", release}
+	if namespace != "" {
+		args = append(args, "--namespace", namespace)
+	}
+	cmd := exec.Command(os.Getenv("HELM_BIN"), args...)
+	return cmd.Output()
+}
+
+func getRevision(release string, revision int, namespace string) ([]byte, error) {
+	args := []string{"get", "manifest", release, "--revision", strconv.Itoa(revision)}
+	if namespace != "" {
+		args = append(args, "--namespace", namespace)
+	}
+	cmd := exec.Command(os.Getenv("HELM_BIN"), args...)
+	return cmd.Output()
+}
+
+func getChart(release, namespace string) (string, error) {
+	args := []string{"get", release, "--template", "{{.Release.Chart.Name}}"}
+	if namespace != "" {
+		args = append(args, "--namespace", namespace)
+	}
+	cmd := exec.Command(os.Getenv("HELM_BIN"), args...)
+	out, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	return string(out), nil
+}
+
+func (d *diffCmd) template() ([]byte, error) {
+	flags := []string{}
+	if d.devel {
+		flags = append(flags, "--devel")
+	}
+	if d.noHooks {
+		flags = append(flags, "--no-hooks")
+	}
+	if d.chartVersion != "" {
+		flags = append(flags, "--version", d.chartVersion)
+	}
+	if d.namespace != "" {
+		flags = append(flags, "--namespace", d.namespace)
+	}
+	if !d.resetValues {
+		if d.reuseValues {
+			tmpfile, err := ioutil.TempFile("", "existing-values")
+			if err != nil {
+				return nil, err
+			}
+			defer os.Remove(tmpfile.Name())
+			flags = append(flags, "--values", tmpfile.Name())
+		}
+		for _, value := range d.values {
+			flags = append(flags, "--set", value)
+		}
+		for _, stringValue := range d.stringValues {
+			flags = append(flags, "--set-string", stringValue)
+		}
+		for _, valueFile := range d.valueFiles {
+			flags = append(flags, "--values", valueFile)
+		}
+		for _, fileValue := range d.fileValues {
+			flags = append(flags, "--set-file", fileValue)
+		}
+	}
+
+	args := []string{"template", d.release, d.chart}
+	args = append(args, flags...)
+	cmd := exec.Command(os.Getenv("HELM_BIN"), args...)
+	return cmd.Output()
+}
+
+func (d *diffCmd) existingValues(f *os.File) error {
+	cmd := exec.Command(os.Getenv("HELM_BIN"), "get", "values", d.release, "--all")
+	defer f.Close()
+	cmd.Stdout = f
+	return cmd.Run()
+}

cmd/helpers.go

@@ -24,6 +24,10 @@ var (
 	DefaultHelmHome = filepath.Join(homedir.HomeDir(), ".helm")
 )
 
+func isHelm3() bool {
+	return os.Getenv("TILLER_HOST") == ""
+}
+
 func addCommonCmdOptions(f *flag.FlagSet) {
 	settings.AddFlagsTLS(f)
 	settings.InitTLS(f)

cmd/release.go

@@ -60,6 +60,9 @@ func releaseCmd() *cobra.Command {
 			}
 
 			diff.releases = args[0:]
+			if isHelm3() {
+				return diff.differentiateHelm3()
+			}
 			if diff.client == nil {
 				diff.client = createHelmClient()
 			}
@@ -70,14 +73,55 @@ func releaseCmd() *cobra.Command {
 	releaseCmd.Flags().BoolP("suppress-secrets", "q", false, "suppress secrets in the output")
 	releaseCmd.Flags().StringArrayVar(&diff.suppressedKinds, "suppress", []string{}, "allows suppression of the values listed in the diff output")
 	releaseCmd.Flags().IntVarP(&diff.outputContext, "context", "C", -1, "output NUM lines of context around changes")
-	releaseCmd.Flags().BoolVar(&diff.includeTests, "include-tests", false, "enable the diffing of the helm test hooks")
+	if !isHelm3() {
+		releaseCmd.Flags().BoolVar(&diff.includeTests, "include-tests", false, "enable the diffing of the helm test hooks")
+	}
 	releaseCmd.SuggestionsMinimumDistance = 1
 
 	addCommonCmdOptions(releaseCmd.Flags())
 
 	return releaseCmd
 }
 
+func (d *release) differentiateHelm3() error {
+	releaseResponse1, err := getRelease(d.releases[0], "")
+	if err != nil {
+		return err
+	}
+	releaseChart1, err := getChart(d.releases[0], "")
+	if err != nil {
+		return err
+	}
+
+	releaseResponse2, err := getRelease(d.releases[1], "")
+	if err != nil {
+		return err
+	}
+	releaseChart2, err := getChart(d.releases[1], "")
+	if err != nil {
+		return err
+	}
+
+	if releaseChart1 == releaseChart2 {
+		seenAnyChanges := diff.Releases(
+			manifest.Parse(string(releaseResponse1), ""),
+			manifest.Parse(string(releaseResponse2), ""),
+			d.suppressedKinds,
+			d.outputContext,
+			os.Stdout)
+
+		if d.detailedExitCode && seenAnyChanges {
+			return Error{
+				error: errors.New("identified at least one change, exiting with non-zero exit code (detailed-exitcode parameter enabled)"),
+				Code:  2,
+			}
+		}
+	} else {
+		fmt.Printf("Error : Incomparable Releases \n Unable to compare releases from two different charts \"%s\", \"%s\". \n try helm diff release --help to know more \n", releaseChart1, releaseChart2)
+	}
+	return nil
+}
+
 func (d *release) differentiate() error {
 
 	releaseResponse1, err := d.client.ReleaseContent(d.releases[0])

cmd/revision.go

@@ -70,6 +70,9 @@ func revisionCmd() *cobra.Command {
 
 			diff.release = args[0]
 			diff.revisions = args[1:]
+			if isHelm3() {
+				return diff.differentiateHelm3()
+			}
 			if diff.client == nil {
 				diff.client = createHelmClient()
 			}
@@ -80,14 +83,76 @@ func revisionCmd() *cobra.Command {
 	revisionCmd.Flags().BoolP("suppress-secrets", "q", false, "suppress secrets in the output")
 	revisionCmd.Flags().StringArrayVar(&diff.suppressedKinds, "suppress", []string{}, "allows suppression of the values listed in the diff output")
 	revisionCmd.Flags().IntVarP(&diff.outputContext, "context", "C", -1, "output NUM lines of context around changes")
-	revisionCmd.Flags().BoolVar(&diff.includeTests, "include-tests", false, "enable the diffing of the helm test hooks")
+	if !isHelm3() {
+		revisionCmd.Flags().BoolVar(&diff.includeTests, "include-tests", false, "enable the diffing of the helm test hooks")
+	}
 	revisionCmd.SuggestionsMinimumDistance = 1
 
 	addCommonCmdOptions(revisionCmd.Flags())
 
 	return revisionCmd
 }
 
+func (d *revision) differentiateHelm3() error {
+	switch len(d.revisions) {
+	case 1:
+		releaseResponse, err := getRelease(d.release, "")
+
+		if err != nil {
+			return err
+		}
+
+		revision, _ := strconv.Atoi(d.revisions[0])
+		revisionResponse, err := getRevision(d.release, revision, "")
+		if err != nil {
+			return err
+		}
+
+		diff.Manifests(
+			manifest.Parse(string(revisionResponse), ""),
+			manifest.Parse(string(releaseResponse), ""),
+			d.suppressedKinds,
+			d.outputContext,
+			os.Stdout)
+
+	case 2:
+		revision1, _ := strconv.Atoi(d.revisions[0])
+		revision2, _ := strconv.Atoi(d.revisions[1])
+		if revision1 > revision2 {
+			revision1, revision2 = revision2, revision1
+		}
+
+		revisionResponse1, err := getRevision(d.release, revision1, "")
+		if err != nil {
+			return prettyError(err)
+		}
+
+		revisionResponse2, err := getRevision(d.release, revision2, "")
+		if err != nil {
+			return prettyError(err)
+		}
+
+		seenAnyChanges := diff.Manifests(
+			manifest.Parse(string(revisionResponse1), ""),
+			manifest.Parse(string(revisionResponse2), ""),
+			d.suppressedKinds,
+			d.outputContext,
+			os.Stdout)
+
+		if d.detailedExitCode && seenAnyChanges {
+			return Error{
+				error: errors.New("identified at least one change, exiting with non-zero exit code (detailed-exitcode parameter enabled)"),
+				Code:  2,
+			}
+		}
+
+	default:
+		return errors.New("Invalid Arguments")
+	}
+
+	return nil
+}
+
 func (d *revision) differentiate() error {
 
 	switch len(d.revisions) {

cmd/rollback.go

@@ -60,6 +60,10 @@ func rollbackCmd() *cobra.Command {
 			diff.release = args[0]
 			diff.revisions = args[1:]
 
+			if isHelm3() {
+				return diff.backcastHelm3()
+			}
+
 			if diff.client == nil {
 				diff.client = createHelmClient()
 			}
@@ -71,14 +75,49 @@ func rollbackCmd() *cobra.Command {
 	rollbackCmd.Flags().BoolP("suppress-secrets", "q", false, "suppress secrets in the output")
 	rollbackCmd.Flags().StringArrayVar(&diff.suppressedKinds, "suppress", []string{}, "allows suppression of the values listed in the diff output")
 	rollbackCmd.Flags().IntVarP(&diff.outputContext, "context", "C", -1, "output NUM lines of context around changes")
-	rollbackCmd.Flags().BoolVar(&diff.includeTests, "include-tests", false, "enable the diffing of the helm test hooks")
+	if !isHelm3() {
+		rollbackCmd.Flags().BoolVar(&diff.includeTests, "include-tests", false, "enable the diffing of the helm test hooks")
+	}
 	rollbackCmd.SuggestionsMinimumDistance = 1
 
 	addCommonCmdOptions(rollbackCmd.Flags())
 
 	return rollbackCmd
 }
 
+func (d *rollback) backcastHelm3() error {
+	// get manifest of the latest release
+	releaseResponse, err := getRelease(d.release, "")
+
+	if err != nil {
+		return err
+	}
+
+	// get manifest of the release to rollback
+	revision, _ := strconv.Atoi(d.revisions[0])
+	revisionResponse, err := getRevision(d.release, revision, "")
+	if err != nil {
+		return err
+	}
+
+	// create a diff between the current manifest and the version of the manifest that a user is intended to rollback
+	seenAnyChanges := diff.Manifests(
+		manifest.Parse(string(releaseResponse), ""),
+		manifest.Parse(string(revisionResponse), ""),
+		d.suppressedKinds,
+		d.outputContext,
+		os.Stdout)
+
+	if d.detailedExitCode && seenAnyChanges {
+		return Error{
+			error: errors.New("identified at least one change, exiting with non-zero exit code (detailed-exitcode parameter enabled)"),
+			Code:  2,
+		}
+	}
+
+	return nil
+}
+
 func (d *rollback) backcast() error {
 
 	// get manifest of the latest release