New output flag for list command (#1215)

* New output flag for list command

Support output as json
Add new formatters file to handle extrac formatting to its own concern
New config interface to support list command specification

* Fix usage message

* Add error handling for formatters

main.go

@@ -471,7 +471,13 @@ func main() {
 		{
 			Name:  "list",
 			Usage: "list releases defined in state file",
-			Flags: []cli.Flag{},
+			Flags: []cli.Flag{
+				cli.StringFlag{
+					Name:  "output",
+					Value: "",
+					Usage: "output releases list as a json string",
+				},
+			},
 			Action: action(func(run *app.App, c configImpl) error {
 				return run.ListReleases(c)
 			}),
@@ -597,6 +603,12 @@ func (c configImpl) Timeout() int {
 	return c.c.Int("timeout")
 }
 
+// ListConfig
+
+func (c configImpl) Output() string {
+	return c.c.String("output")
+}
+
 // GlobalConfig
 
 func (c configImpl) HelmBinary() string {

pkg/app/app.go

@@ -14,7 +14,6 @@ import (
 	"syscall"
 	"text/tabwriter"
 
-	"github.com/gosuri/uitable"
 	"github.com/roboll/helmfile/pkg/argparser"
 	"github.com/roboll/helmfile/pkg/helmexec"
 	"github.com/roboll/helmfile/pkg/remote"
@@ -60,6 +59,13 @@ type App struct {
 	helmsMutex sync.Mutex
 }
 
+type HelmRelease struct {
+	Name      string `json:"name"`
+	Namespace string `json:"namespace"`
+	Enabled   bool   `json:"enabled"`
+	Labels    string `json:"labels"`
+}
+
 func New(conf ConfigProvider) *App {
 	return Init(&App{
 		OverrideKubeContext: conf.KubeContext(),
@@ -259,9 +265,8 @@ func (a *App) PrintState(c StateConfigProvider) error {
 	})
 }
 
-func (a *App) ListReleases(c StateConfigProvider) error {
-	table := uitable.New()
-	table.AddRow("NAME", "NAMESPACE", "ENABLED", "LABELS")
+func (a *App) ListReleases(c ListConfigProvider) error {
+	var releases []*HelmRelease
 
 	err := a.VisitDesiredStatesWithReleasesFiltered(a.FileOrDir, func(st *state.HelmState) []error {
 		//var releases m
@@ -270,12 +275,28 @@ func (a *App) ListReleases(c StateConfigProvider) error {
 			for k, v := range r.Labels {
 				labels = fmt.Sprintf("%s,%s:%s", labels, k, v)
 			}
+			labels = strings.Trim(labels, ",")
 			installed := r.Installed == nil || *r.Installed
-			table.AddRow(r.Name, r.Namespace, fmt.Sprintf("%t", installed), strings.Trim(labels, ","))
+			releases = append(releases, &HelmRelease{
+				Name:      r.Name,
+				Namespace: r.Namespace,
+				Enabled:   installed,
+				Labels:    labels,
+			})
 		}
 		return []error{}
 	})
-	fmt.Println(table.String())
+
+	if err != nil {
+		return err
+	}
+
+	if c.Output() == "json" {
+		err = FormatAsJson(releases)
+	} else {
+		err = FormatAsTable(releases)
+	}
+
 	return err
 }
 

pkg/app/app_test.go

@@ -1962,7 +1962,8 @@ services:
 }
 
 type configImpl struct {
-	set []string
+	set    []string
+	output string
 }
 
 func (c configImpl) Set() []string {
@@ -1993,6 +1994,10 @@ func (c configImpl) Concurrency() int {
 	return 1
 }
 
+func (c configImpl) Output() string {
+	return c.output
+}
+
 type applyConfig struct {
 	args              string
 	values            []string
@@ -3849,6 +3854,63 @@ myrelease4	         	true   	id:myrelease1
 	assert.Equal(t, expected, out)
 }
 
+func TestListWithJsonOutput(t *testing.T) {
+	files := map[string]string{
+		"/path/to/helmfile.d/first.yaml": `
+releases:
+- name: myrelease1
+  chart: mychart1
+  installed: no
+  labels:
+    id: myrelease1
+- name: myrelease2
+  chart: mychart1
+`,
+		"/path/to/helmfile.d/second.yaml": `
+releases:
+- name: myrelease3
+  chart: mychart1
+  installed: yes
+- name: myrelease4
+  chart: mychart1
+  labels:
+    id: myrelease1
+`,
+	}
+	stdout := os.Stdout
+	defer func() { os.Stdout = stdout }()
+
+	var buffer bytes.Buffer
+	logger := helmexec.NewLogger(&buffer, "debug")
+
+	app := appWithFs(&App{
+		OverrideHelmBinary:  DefaultHelmBinary,
+		glob:                filepath.Glob,
+		abs:                 filepath.Abs,
+		OverrideKubeContext: "default",
+		Env:                 "default",
+		Logger:              logger,
+		Namespace:           "testNamespace",
+	}, files)
+
+	expectNoCallsToHelm(app)
+
+	out := captureStdout(func() {
+		err := app.ListReleases(configImpl{
+			output: "json",
+		})
+		assert.NilError(t, err)
+	})
+
+	expected := "[" +
+		"{\"name\":\"myrelease1\",\"namespace\":\"\",\"enabled\":false,\"labels\":\"id:myrelease1\"}," +
+		"{\"name\":\"myrelease2\",\"namespace\":\"\",\"enabled\":true,\"labels\":\"\"}," +
+		"{\"name\":\"myrelease3\",\"namespace\":\"\",\"enabled\":true,\"labels\":\"\"}," +
+		"{\"name\":\"myrelease4\",\"namespace\":\"\",\"enabled\":true,\"labels\":\"id:myrelease1\"}" +
+		"]\n"
+	assert.Equal(t, expected, out)
+}
+
 func TestSetValuesTemplate(t *testing.T) {
 	files := map[string]string{
 		"/path/to/helmfile.yaml": `

pkg/app/config.go

@@ -156,3 +156,7 @@ type loggingConfig interface {
 type interactive interface {
 	Interactive() bool
 }
+
+type ListConfigProvider interface {
+	Output() string
+}

pkg/app/formatters.go

@@ -0,0 +1,33 @@
+package app
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/gosuri/uitable"
+)
+
+func FormatAsTable(releases []*HelmRelease) error {
+	table := uitable.New()
+	table.AddRow("NAME", "NAMESPACE", "ENABLED", "LABELS")
+
+	for _, r := range releases {
+		table.AddRow(r.Name, r.Namespace, fmt.Sprintf("%t", r.Enabled), r.Labels)
+	}
+
+	fmt.Println(table.String())
+
+	return nil
+}
+
+func FormatAsJson(releases []*HelmRelease) error {
+	output, err := json.Marshal(releases)
+
+	if err != nil {
+		return fmt.Errorf("error generating json: %v", err)
+	}
+
+	fmt.Println(string(output))
+
+	return nil
+}