Merge pull request #15 from ContainerSolutions/pretty-kustomization-yaml

Pretty print kustomization.yaml

cmd/convert.go

@@ -50,6 +50,7 @@ type convertCmd struct {
 	version          string
 	depUp            bool
 	forceGen         bool
+	comments         bool
 
 	username string
 	password string
@@ -133,6 +134,7 @@ func NewConvertCommand() *cobra.Command {
 	f.BoolVar(&k.forceGen, "force", false, "convert chart even if the destination directory already exists")
 	f.StringVar(&k.username, "username", "", "chart repository username")
 	f.StringVar(&k.password, "password", "", "chart repository password")
+	f.BoolVar(&k.comments, "comments", true, "add default comments to kustomization.yaml file")
 
 	// log to stderr by default,
 	flag.Set("logtostderr", "true")
@@ -257,7 +259,7 @@ func (k *convertCmd) run() error {
 
 	// write to disk
 	generator := generators.NewGenerator(k.forceGen)
-	err = generator.Render(k.destination, config, chartRequested.Metadata, resources)
+	err = generator.Render(k.destination, config, chartRequested.Metadata, resources, k.comments)
 	if err != nil {
 		return err
 	}

pkg/generators/comments.go

@@ -0,0 +1,30 @@
+package generators
+
+var commentsMapping = map[string]string{
+	"namespace": "# Adds namespace to all resources.",
+	"namePrefix": "# Value of this field is prepended to the\n" +
+		"# names of all resources",
+	"commonLabels": "# Labels to add to all resources and selectors.",
+	"commonAnnotations": "# Annotations (non-identifying metadata)\n" +
+		"# to add to all resources. Like labels,\n" +
+		"# these are key value pairs.",
+	"resources": "# List of resource files that kustomize reads, modifies\n" +
+		"# and emits as a YAML string",
+	"configMapGenerator": "# Each entry in this list results in the creation of\n" +
+		"# one ConfigMap resource (it's a generator of n maps).",
+	"secretGenerator": "# Each entry in this list results in the creation of\n" +
+		"# one Secret resource (it's a generator of n secrets).",
+	"generatorOptions": "# generatorOptions modify behavior of all ConfigMap\n" +
+		"# and Secret generators",
+	"patches": "# Each entry in this list should resolve to\n" +
+		"# a partial or complete resource definition file.",
+	"patchesJson6902": "# Each entry in this list should resolve to\n" +
+		"# a kubernetes object and a JSON patch that will be applied\n" +
+		"# to the object.",
+	"crds": "# Each entry in this list should be a relative path to\n" +
+		"# a file for custom resource definition(CRD).",
+	"vars": "# Vars are used to insert values from resources that cannot\n" +
+		"# be referenced otherwise.",
+	"imageTags": "# ImageTags modify the tags for images without\n" +
+		"# creating patches.",
+}

pkg/generators/generators.go

@@ -4,15 +4,12 @@ package generators
 import (
 	"bufio"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path"
 	"strings"
 
 	"github.com/ContainerSolutions/helm-convert/pkg/types"
 	"github.com/ContainerSolutions/helm-convert/pkg/utils"
-	"github.com/ghodss/yaml"
-	"github.com/golang/glog"
 	"k8s.io/helm/pkg/proto/hapi/chart"
 	ktypes "sigs.k8s.io/kustomize/pkg/types"
 )
@@ -36,7 +33,7 @@ func NewGenerator(force bool) *Generator {
 }
 
 // Render to disk the kustomization.yaml, Kube-descriptor.yaml and associated resources
-func (g *Generator) Render(destination string, config *ktypes.Kustomization, metadata *chart.Metadata, resources *types.Resources) error {
+func (g *Generator) Render(destination string, config *ktypes.Kustomization, metadata *chart.Metadata, resources *types.Resources, addConfigComments bool) error {
 	var err error
 
 	// chech if destination path already exist, prompt user to confirm override
@@ -82,30 +79,14 @@ func (g *Generator) Render(destination string, config *ktypes.Kustomization, met
 		return err
 	}
 
-	// render Kube-descriptor.yaml
-	err = writeYamlFile(path.Join(destination, DefaultKubeDescriptorFilename), metadata)
-	if err != nil {
-		return err
-	}
-
-	return nil
-}
-
-// writeYamlFile write a given interface into yaml
-func writeYamlFile(filePath string, data interface{}) error {
-	output, err := yaml.Marshal(data)
+	// format and write kustomization.yaml
+	err = writeAndFormatKustomizationConfig(path.Join(destination, DefaultKustomizationFilename), addConfigComments)
 	if err != nil {
 		return err
 	}
 
-	return writeFile(filePath, output, 0644)
-}
-
-// writeFile writes data to a file named by filename.
-func writeFile(filePath string, data []byte, perm os.FileMode) error {
-	glog.V(4).Infof("Writing %s", filePath)
-
-	err := ioutil.WriteFile(filePath, data, perm)
+	// render Kube-descriptor.yaml
+	err = writeYamlFile(path.Join(destination, DefaultKubeDescriptorFilename), metadata)
 	if err != nil {
 		return err
 	}

pkg/generators/utils.go

@@ -0,0 +1,78 @@
+package generators
+
+import (
+	"bufio"
+	"io/ioutil"
+	"os"
+	"regexp"
+	"strings"
+
+	"github.com/ghodss/yaml"
+	"github.com/golang/glog"
+)
+
+// Pattern used to detect if a line contains a YAML key
+var yamlKeyPattern = regexp.MustCompile("^[^ :]*:")
+
+// writeYamlFile write a given interface into yaml
+func writeYamlFile(filePath string, data interface{}) error {
+	output, err := yaml.Marshal(data)
+	if err != nil {
+		return err
+	}
+
+	return writeFile(filePath, output, 0644)
+}
+
+// writeAndFormatKustomizationConfig adds line break and comments
+func writeAndFormatKustomizationConfig(filePath string, comments bool) error {
+	glog.V(4).Infof("Formatting %s", filePath)
+
+	file, err := os.Open(filePath)
+	if err != nil {
+		return err
+	}
+
+	defer file.Close()
+
+	var output []string
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := scanner.Text()
+
+		// add line break before comment except for if this is the first line
+		if yamlKeyPattern.MatchString(line) && len(output) > 0 {
+			output = append(output, "")
+		}
+
+		// add comments
+		if comments {
+			for key, value := range commentsMapping {
+				if strings.HasPrefix(line, key+":") {
+					output = append(output, value)
+				}
+			}
+		}
+
+		output = append(output, line)
+	}
+
+	if err := scanner.Err(); err != nil {
+		return err
+	}
+
+	return writeFile(filePath, []byte(strings.Join(output, "\n")), 0644)
+}
+
+// writeFile writes data to a file named by filename.
+func writeFile(filePath string, data []byte, perm os.FileMode) error {
+	glog.V(4).Infof("Writing %s", filePath)
+
+	err := ioutil.WriteFile(filePath, data, perm)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}