feat(helm): output option for helm get values command, allow json and yaml formats (#4596)

Signed-off-by: Arash Deshmeh <adeshmeh@ca.ibm.com>

cmd/helm/get_values.go

@@ -17,6 +17,7 @@ limitations under the License.
 package main
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 
@@ -36,6 +37,7 @@ type getValuesCmd struct {
 	out       io.Writer
 	client    helm.Interface
 	version   int32
+	output    string
 }
 
 func newGetValuesCmd(client helm.Interface, out io.Writer) *cobra.Command {
@@ -62,6 +64,7 @@ func newGetValuesCmd(client helm.Interface, out io.Writer) *cobra.Command {
 	settings.AddFlagsTLS(f)
 	f.Int32Var(&get.version, "revision", 0, "get the named release with revision")
 	f.BoolVarP(&get.allValues, "all", "a", false, "dump all (computed) values")
+	f.StringVar(&get.output, "output", "yaml", "output the specified format (json or yaml)")
 	return cmd
 }
 
@@ -72,20 +75,42 @@ func (g *getValuesCmd) run() error {
 		return prettyError(err)
 	}
 
+	values, err := chartutil.ReadValues([]byte(res.Release.Config.Raw))
+	if err != nil {
+		return err
+	}
+
 	// If the user wants all values, compute the values and return.
 	if g.allValues {
-		cfg, err := chartutil.CoalesceValues(res.Release.Chart, res.Release.Config)
+		values, err = chartutil.CoalesceValues(res.Release.Chart, res.Release.Config)
-		if err != nil {
-			return err
-		}
-		cfgStr, err := cfg.YAML()
 		if err != nil {
 			return err
 		}
-		fmt.Fprintln(g.out, cfgStr)
-		return nil
 	}
 
-	fmt.Fprintln(g.out, res.Release.Config.Raw)
+	result, err := formatValues(g.output, values)
+	if err != nil {
+		return err
+	}
+	fmt.Fprintln(g.out, result)
 	return nil
 }
+
+func formatValues(format string, values chartutil.Values) (string, error) {
+	switch format {
+	case "", "yaml":
+		out, err := values.YAML()
+		if err != nil {
+			return "", err
+		}
+		return out, nil
+	case "json":
+		out, err := json.Marshal(values)
+		if err != nil {
+			return "", fmt.Errorf("Failed to Marshal JSON output: %s", err)
+		}
+		return string(out), nil
+	default:
+		return "", fmt.Errorf("Unknown output format %q", format)
+	}
+}

cmd/helm/get_values_test.go

@@ -23,22 +23,53 @@ import (
 	"github.com/spf13/cobra"
 
 	"k8s.io/helm/pkg/helm"
+	"k8s.io/helm/pkg/proto/hapi/chart"
 	"k8s.io/helm/pkg/proto/hapi/release"
 )
 
 func TestGetValuesCmd(t *testing.T) {
+	releaseWithValues := helm.ReleaseMock(&helm.MockReleaseOptions{
+		Name:   "thomas-guide",
+		Chart:  &chart.Chart{Values: &chart.Config{Raw: `foo2: "bar2"`}},
+		Config: &chart.Config{Raw: `foo: "bar"`},
+	})
+
 	tests := []releaseCase{
 		{
 			name:     "get values with a release",
 			resp:     helm.ReleaseMock(&helm.MockReleaseOptions{Name: "thomas-guide"}),
 			args:     []string{"thomas-guide"},
-			expected: "name: \"value\"",
+			expected: "name: value",
 			rels:     []*release.Release{helm.ReleaseMock(&helm.MockReleaseOptions{Name: "thomas-guide"})},
 		},
+		{
+			name:     "get values with json format",
+			resp:     releaseWithValues,
+			args:     []string{"thomas-guide"},
+			flags:    []string{"--output", "json"},
+			expected: "{\"foo\":\"bar\"}",
+			rels:     []*release.Release{releaseWithValues},
+		},
+		{
+			name:     "get all values with json format",
+			resp:     releaseWithValues,
+			args:     []string{"thomas-guide"},
+			flags:    []string{"--all", "--output", "json"},
+			expected: "{\"foo\":\"bar\",\"foo2\":\"bar2\"}",
+			rels:     []*release.Release{releaseWithValues},
+		},
 		{
 			name: "get values requires release name arg",
 			err:  true,
 		},
+		{
+			name:  "get values with invalid output format",
+			resp:  releaseWithValues,
+			args:  []string{"thomas-guide"},
+			flags: []string{"--output", "INVALID_FORMAT"},
+			rels:  []*release.Release{releaseWithValues},
+			err:   true,
+		},
 	}
 	cmd := func(c *helm.FakeClient, out io.Writer) *cobra.Command {
 		return newGetValuesCmd(c, out)

docs/helm/helm_get_values.md

@@ -17,6 +17,7 @@ helm get values [flags] RELEASE_NAME
 ```
   -a, --all                   dump all (computed) values
   -h, --help                  help for values
+      --output string         output the specified format (json or yaml) (default "yaml")
       --revision int32        get the named release with revision
       --tls                   enable TLS for request
       --tls-ca-cert string    path to TLS CA certificate file (default "$HELM_HOME/ca.pem")
@@ -42,4 +43,4 @@ helm get values [flags] RELEASE_NAME
 
 * [helm get](helm_get.md)	 - download a named release
 
-###### Auto generated by spf13/cobra on 10-Aug-2018
+###### Auto generated by spf13/cobra on 7-Sep-2018