Add asset generation generate cmd

Signed-off-by: Jordi Gil <jgil@redhat.com>
Signed-off-by: Gloria Ciavarrini <gciavarrini@redhat.com>

cmd/asset_generation/generate/generate.go

@@ -0,0 +1,21 @@
+package generate
+
+import (
+	"github.com/go-logr/logr"
+	"github.com/konveyor-ecosystem/kantra/cmd/asset_generation/generate/helm"
+	"github.com/spf13/cobra"
+)
+
+func NewGenerateCommand(log logr.Logger) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:     "generate",
+		GroupID: "assetGeneration",
+		Short:   "Analyze the source platform and/or application and output discovery manifest.",
+		Run: func(cmd *cobra.Command, _ []string) {
+			cmd.Help()
+		},
+	}
+	cmd.AddCommand(helm.NewGenerateHelmCommand(log))
+
+	return cmd
+}

cmd/asset_generation/generate/generate_suite_test.go

@@ -0,0 +1,13 @@
+package generate_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestGenerate(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Generate Suite")
+}

cmd/asset_generation/generate/generate_test.go

@@ -0,0 +1,68 @@
+package generate_test
+
+import (
+	"bufio"
+	"bytes"
+
+	"github.com/bombsimon/logrusr/v3"
+	"github.com/go-logr/logr"
+	"github.com/konveyor-ecosystem/kantra/cmd/asset_generation/generate"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	"github.com/sirupsen/logrus"
+	"github.com/spf13/cobra"
+)
+
+var _ = Describe("Generate Command", func() {
+
+	var _ = Context("Flag Behavior Verification", func() {
+
+		var (
+			logger logr.Logger
+			out    bytes.Buffer
+			err    bytes.Buffer
+			writer *bufio.Writer = bufio.NewWriter(&out)
+			c      *cobra.Command
+		)
+
+		var _ = BeforeEach(func() {
+			// Reset buffers before each test
+			writer.Reset(&out)
+
+			// Set up logger
+			logrusLog := logrus.New()
+			logrusLog.SetOutput(&out)
+			logrusLog.SetFormatter(&logrus.TextFormatter{})
+			logger = logrusr.New(logrusLog)
+
+			// Create command instance
+			c = generate.NewGenerateCommand(logger)
+			c.SetOut(writer)
+			c.SetErr(&err)
+		})
+
+		DescribeTable("Command Flag Behavior",
+			func(args []string, expectedOutput string, expectError bool, expectedError string) {
+				c.SetArgs(args)
+				err := c.Execute()
+				writer.Flush()
+				if expectError {
+					Expect(err).To(HaveOccurred())
+					Expect(err).Should(MatchError(expectedError))
+				} else {
+					Expect(err).NotTo(HaveOccurred())
+				}
+				Expect(out.String()).To(ContainSubstring(expectedOutput))
+
+			},
+			Entry("should print the help message when no flags are used containing entries for each template engine",
+				[]string{}, "helm        generate the helm template manifests", false, ""),
+
+			Entry("should return an error message for an invalid command",
+				[]string{"invalid-command"}, "", true, "unknown command \"invalid-command\" for \"generate\""),
+
+			Entry("should return an error message for an invalid flag",
+				[]string{"--invalid-flag"}, "Usage:\n", true, "unknown flag: --invalid-flag"),
+		)
+	})
+})

cmd/asset_generation/generate/helm/helm.go

@@ -0,0 +1,192 @@
+package helm
+
+import (
+	"fmt"
+	"io"
+	"maps"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/go-logr/logr"
+	"github.com/spf13/cobra"
+	"gopkg.in/yaml.v3"
+	"k8s.io/helm/pkg/strvals"
+
+	"helm.sh/helm/v3/pkg/chart"
+	"helm.sh/helm/v3/pkg/chart/loader"
+	"helm.sh/helm/v3/pkg/chartutil"
+	"helm.sh/helm/v3/pkg/engine"
+)
+
+const (
+	konveyorDirectoryName = "files/konveyor"
+)
+
+var (
+	input      string
+	outputDir  string
+	chartDir   string
+	nonK8SOnly bool
+	setValues  []string
+)
+
+func NewGenerateHelmCommand(log logr.Logger) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "helm",
+		Short: "generate the helm template manifests",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return helm(cmd.OutOrStdout())
+		},
+	}
+	cmd.Flags().StringVar(&chartDir, "chart-dir", "", "Directory to the Helm chart to use for chart generation.")
+	cmd.Flags().StringVar(&input, "input", "", "Specifies the discover manifest file")
+	cmd.Flags().StringVar(&outputDir, "output-dir", "", "Directory to save the generated Helm chart. Defaults to stdout")
+	cmd.Flags().BoolVar(&nonK8SOnly, "non-k8s-only", false, "Render only the non-Kubernetes templates located in the files/konveyor directory of the chart")
+	cmd.Flags().StringArrayVar(&setValues, "set", []string{}, "Set values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)")
+
+	// Validation
+	cmd.MarkFlagDirname("chart-dir")
+	cmd.MarkFlagDirname("output-dir")
+	cmd.MarkFlagFilename("input")
+	// Required
+	cmd.MarkFlagRequired("chart-dir")
+	cmd.MarkFlagRequired("input")
+
+	return cmd
+}
+
+func helm(out io.Writer) error {
+	chart, err := loadChart()
+	if err != nil {
+		return err
+	}
+	values, err := loadDiscoverManifest()
+	if err != nil {
+		return err
+	}
+	if len(setValues) > 0 {
+		v, err := parseValues()
+		if err != nil {
+			return err
+		}
+		maps.Copy(values, v)
+	}
+	chart.Values = values
+	rendered := make(map[string]string)
+	if !nonK8SOnly {
+		rendered, err = generateK8sTemplates(*chart)
+		if err != nil {
+			return err
+		}
+	}
+	r, err := generateNonK8sTemplates(*chart)
+	if err != nil {
+		return err
+	}
+	maps.Copy(rendered, r)
+
+	o := output{out: out}
+	print := o.toStdout
+	if outputDir != "" {
+		err = os.MkdirAll(outputDir, 0755)
+		if err != nil {
+			return err
+		}
+		print = toFile
+	}
+	for f, c := range rendered {
+		err = print(f, c)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+type output struct {
+	out io.Writer
+}
+
+func (o output) toStdout(filename, contents string) error {
+	fmt.Fprintf(o.out, "---\n# Source: %s\n%s", filename, contents)
+	return nil
+}
+
+func toFile(filename, contents string) error {
+	fn := filepath.Base(filename)
+	dst := filepath.Join(outputDir, fn)
+	// Add an extra line to make it yaml compliant since helm doesn't seem to do it.
+	contents = fmt.Sprintln(contents)
+	return os.WriteFile(dst, []byte(contents), 0644)
+}
+
+func loadChart() (*chart.Chart, error) {
+	l, err := loader.Loader(chartDir)
+	if err != nil {
+		return nil, fmt.Errorf("unable to load chart: %s", err)
+	}
+	return l.Load()
+}
+
+func loadDiscoverManifest() (map[string]interface{}, error) {
+	d, err := os.ReadFile(input)
+	if err != nil {
+		return nil, fmt.Errorf("unable to load discover manifest: %s", err)
+	}
+	var m map[string]interface{}
+	err = yaml.Unmarshal(d, &m)
+	return m, err
+}
+
+func generateK8sTemplates(chart chart.Chart) (map[string]string, error) {
+	return generateTemplates(chart)
+}
+
+func generateNonK8sTemplates(chart chart.Chart) (map[string]string, error) {
+	chart.Templates = filterTemplatesByPath(konveyorDirectoryName, chart.Files)
+	return generateTemplates(chart)
+}
+
+func generateTemplates(chart chart.Chart) (map[string]string, error) {
+	e := engine.Engine{}
+	options := chartutil.ReleaseOptions{
+		Name:      chart.Name(),
+		Namespace: "",
+		Revision:  1,
+		IsInstall: false,
+		IsUpgrade: false,
+	}
+	valuesToRender, err := chartutil.ToRenderValues(&chart, chart.Values, options, chartutil.DefaultCapabilities.Copy())
+	if err != nil {
+		return nil, fmt.Errorf("failed to render the values for chart %s: %s", chart.Name(), err)
+	}
+	chart.Values = valuesToRender
+	rendered, err := e.Render(&chart, valuesToRender)
+	if err != nil {
+		return nil, fmt.Errorf("failed to render the templates for chart %s: %s", chart.Name(), err)
+	}
+	return rendered, nil
+
+}
+
+func filterTemplatesByPath(pathPrefix string, files []*chart.File) []*chart.File {
+	ret := []*chart.File{}
+	for _, f := range files {
+		if strings.HasPrefix(f.Name, pathPrefix) {
+			ret = append(ret, f)
+		}
+	}
+	return ret
+}
+
+func parseValues() (map[string]interface{}, error) {
+	// User specified a value via --set
+	base := make(map[string]interface{})
+	for _, value := range setValues {
+		if err := strvals.ParseInto(value, base); err != nil {
+			return nil, fmt.Errorf("failed parsing --set data:%s", err)
+		}
+	}
+	return base, nil
+}

cmd/asset_generation/generate/helm/helm_suite_test.go

@@ -0,0 +1,13 @@
+package helm_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestHelm(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Helm Suite")
+}