feat(*): add --output flag to 'helm dependency list'

Signed-off-by: Pablo Caraballo Llorente <pcaraballo@vmware.com>

cmd/helm/dependency.go

@@ -17,7 +17,6 @@ package main
 
 import (
 	"io"
-	"path/filepath"
 
 	"github.com/spf13/cobra"
 
@@ -97,26 +96,3 @@ func newDependencyCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 
 	return cmd
 }
-
-func newDependencyListCmd(out io.Writer) *cobra.Command {
-	client := action.NewDependency()
-	cmd := &cobra.Command{
-		Use:     "list CHART",
-		Aliases: []string{"ls"},
-		Short:   "list the dependencies for the given chart",
-		Long:    dependencyListDesc,
-		Args:    require.MaximumNArgs(1),
-		RunE: func(cmd *cobra.Command, args []string) error {
-			chartpath := "."
-			if len(args) > 0 {
-				chartpath = filepath.Clean(args[0])
-			}
-			return client.List(chartpath, out)
-		},
-	}
-
-	f := cmd.Flags()
-
-	f.UintVar(&client.ColumnWidth, "max-col-width", 80, "maximum column width for output table")
-	return cmd
-}

cmd/helm/dependency_list.go

@@ -0,0 +1,104 @@
+/*
+Copyright The Helm Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package main
+
+import (
+	"io"
+	"path/filepath"
+
+	"github.com/gosuri/uitable"
+	"github.com/spf13/cobra"
+
+	"helm.sh/helm/v3/cmd/helm/require"
+	"helm.sh/helm/v3/pkg/action"
+	"helm.sh/helm/v3/pkg/cli/output"
+)
+
+func newDependencyListCmd(out io.Writer) *cobra.Command {
+	var outfmt output.Format
+	client := action.NewDependency()
+	cmd := &cobra.Command{
+		Use:     "list CHART",
+		Aliases: []string{"ls"},
+		Short:   "list the dependencies for the given chart",
+		Long:    dependencyListDesc,
+		Args:    require.MaximumNArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			chartpath := "."
+			if len(args) > 0 {
+				chartpath = filepath.Clean(args[0])
+			}
+
+			dependencies, err := action.ListDependencies(chartpath, out)
+
+			if err != nil {
+				return err
+			}
+
+			if dependencies != nil {
+				if outfmt == output.Table {
+					action.PrintMissing(chartpath, out, dependencies)
+				}
+
+				var deplist = make([]dependencyElement, 0, len(dependencies))
+
+				for _, d := range dependencies {
+					deplist = append(deplist, dependencyElement{Name: d.Name, Version: d.Version, Repository: d.Repository, Status: d.Status})
+				}
+
+				return outfmt.Write(out, &dependencyListWriter{deps: deplist, columnWidth: client.ColumnWidth})
+			}
+
+			return nil
+		},
+	}
+
+	f := cmd.Flags()
+
+	f.UintVar(&client.ColumnWidth, "max-col-width", 80, "maximum column width for output table")
+	bindOutputFlag(cmd, &outfmt)
+
+	return cmd
+}
+
+type dependencyElement struct {
+	Name       string `json:"name"`
+	Version    string `json:"version"`
+	Repository string `json:"repository"`
+	Status     string `json:"status"`
+}
+
+type dependencyListWriter struct {
+	deps        []dependencyElement
+	columnWidth uint
+}
+
+func (d *dependencyListWriter) WriteTable(out io.Writer) error {
+	table := uitable.New()
+	table.MaxColWidth = d.columnWidth
+	table.AddRow("NAME", "VERSION", "REPOSITORY", "STATUS")
+	for _, row := range d.deps {
+		table.AddRow(row.Name, row.Version, row.Repository, row.Status)
+	}
+	return output.EncodeTable(out, table)
+}
+
+func (d *dependencyListWriter) WriteJSON(out io.Writer) error {
+	return output.EncodeJSON(out, d.deps)
+}
+
+func (d *dependencyListWriter) WriteYAML(out io.Writer) error {
+	return output.EncodeYAML(out, d.deps)
+}

pkg/action/dependency.go

@@ -24,7 +24,6 @@ import (
 	"strings"
 
 	"github.com/Masterminds/semver/v3"
-	"github.com/gosuri/uitable"
 
 	"helm.sh/helm/v3/pkg/chart"
 	"helm.sh/helm/v3/pkg/chart/loader"
@@ -40,6 +39,14 @@ type Dependency struct {
 	ColumnWidth uint
 }
 
+// DependencyEntry is the representation of a chart dependency, returned back to the user after running `helm dep list`
+type DependencyEntry struct {
+	Name       string
+	Version    string
+	Repository string
+	Status     string
+}
+
 // NewDependency creates a new Dependency object with the given configuration.
 func NewDependency() *Dependency {
 	return &Dependency{
@@ -48,25 +55,28 @@ func NewDependency() *Dependency {
 }
 
 // List executes 'helm dependency list'.
-func (d *Dependency) List(chartpath string, out io.Writer) error {
+func ListDependencies(chartpath string, out io.Writer) ([]DependencyEntry, error) {
 	c, err := loader.Load(chartpath)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	if c.Metadata.Dependencies == nil {
 		fmt.Fprintf(out, "WARNING: no dependencies at %s\n", filepath.Join(chartpath, "charts"))
-		return nil
+		return nil, nil
+	}
+
+	var deplist = make([]DependencyEntry, 0, len(c.Metadata.Dependencies))
+
+	for _, d := range c.Metadata.Dependencies {
+		deplist = append(deplist, DependencyEntry{Name: d.Name, Version: d.Version, Repository: d.Repository, Status: DependencyStatus(chartpath, d, c)})
 	}
 
-	d.printDependencies(chartpath, out, c)
-	fmt.Fprintln(out)
-	d.printMissing(chartpath, out, c.Metadata.Dependencies)
-	return nil
+	return deplist, nil
 }
 
-// dependencyStatus returns a string describing the status of a dependency viz a viz the parent chart.
-func (d *Dependency) dependencyStatus(chartpath string, dep *chart.Dependency, parent *chart.Chart) string {
+// DependencyStatus returns a string describing the status of a dependency viz a viz the parent chart.
+func DependencyStatus(chartpath string, dep *chart.Dependency, parent *chart.Chart) string {
 	filename := fmt.Sprintf("%s-%s.tgz", dep.Name, "*")
 
 	// If a chart is unpacked, this will check the unpacked chart's `charts/` directory for tarballs.
@@ -181,20 +191,9 @@ func statArchiveForStatus(archive string, dep *chart.Dependency) string {
 	return ""
 }
 
-// printDependencies prints all of the dependencies in the yaml file.
-func (d *Dependency) printDependencies(chartpath string, out io.Writer, c *chart.Chart) {
-	table := uitable.New()
-	table.MaxColWidth = d.ColumnWidth
-	table.AddRow("NAME", "VERSION", "REPOSITORY", "STATUS")
-	for _, row := range c.Metadata.Dependencies {
-		table.AddRow(row.Name, row.Version, row.Repository, d.dependencyStatus(chartpath, row, c))
-	}
-	fmt.Fprintln(out, table)
-}
-
 // printMissing prints warnings about charts that are present on disk, but are
 // not in Chart.yaml.
-func (d *Dependency) printMissing(chartpath string, out io.Writer, reqs []*chart.Dependency) {
+func PrintMissing(chartpath string, out io.Writer, reqs []DependencyEntry) {
 	folder := filepath.Join(chartpath, "charts/*")
 	files, err := filepath.Glob(folder)
 	if err != nil {