commands/.../new,pkg/scaffold/helm: source chart flag for new projects

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ### Added
 
+- New flags for [`operator-sdk new --type=helm`](https://github.com/operator-framework/operator-sdk/blob/master/doc/sdk-cli-reference.md#new), which can be used to populate the project with an existing chart. ([#949](https://github.com/operator-framework/operator-sdk/pull/949))
+
 ### Changed
 
 ### Deprecated

commands/operator-sdk/cmd/new.go

@@ -56,6 +56,10 @@ generates a skeletal app-operator application in $GOPATH/src/github.com/example.
 	newCmd.Flags().BoolVar(&generatePlaybook, "generate-playbook", false, "Generate a playbook skeleton. (Only used for --type ansible)")
 	newCmd.Flags().BoolVar(&isClusterScoped, "cluster-scoped", false, "Generate cluster-scoped resources instead of namespace-scoped")
 
+	newCmd.Flags().StringVar(&helmChartRef, "helm-chart", "", "Initialize helm operator with existing helm chart (<URL>, <repo>/<name>, or local path)")
+	newCmd.Flags().StringVar(&helmChartVersion, "helm-chart-version", "", "Specific version of the helm chart (default is latest version)")
+	newCmd.Flags().StringVar(&helmChartRepo, "helm-chart-repo", "", "Chart repository URL for the requested helm chart")
+
 	return newCmd
 }
 
@@ -67,6 +71,10 @@ var (
 	skipGit          bool
 	generatePlaybook bool
 	isClusterScoped  bool
+
+	helmChartRef     string
+	helmChartVersion string
+	helmChartRepo    string
 )
 
 const (
@@ -256,14 +264,17 @@ func doHelmScaffold() error {
 		ProjectName:    projectName,
 	}
 
-	resource, err := scaffold.NewResource(apiVersion, kind)
-	if err != nil {
-		return err
+	createOpts := helm.CreateChartOptions{
+		ResourceAPIVersion: apiVersion,
+		ResourceKind:       kind,
+		Chart:              helmChartRef,
+		Version:            helmChartVersion,
+		Repo:               helmChartRepo,
 	}
 
-	chart, err := helm.CreateChartForResource(resource, cfg.AbsProjectPath)
+	resource, chart, err := helm.CreateChart(cfg.AbsProjectPath, createOpts)
 	if err != nil {
-		log.Fatalf("Failed to create initial helm chart for resource (%v, %v): (%v)", resource.APIVersion, resource.Kind, err)
+		return fmt.Errorf("failed to create helm chart: %s", err)
 	}
 
 	valuesPath := filepath.Join("<project_dir>", helm.HelmChartsDir, chart.GetMetadata().GetName(), "values.yaml")
@@ -272,7 +283,10 @@ func doHelmScaffold() error {
 	s := &scaffold.Scaffold{}
 	err = s.Execute(cfg,
 		&helm.Dockerfile{},
-		&helm.WatchesYAML{Resource: resource},
+		&helm.WatchesYAML{
+			Resource:  resource,
+			ChartName: chart.GetMetadata().GetName(),
+		},
 		&scaffold.ServiceAccount{},
 		&scaffold.Role{IsClusterScoped: isClusterScoped},
 		&scaffold.RoleBinding{IsClusterScoped: isClusterScoped},
@@ -300,11 +314,26 @@ func verifyFlags() error {
 	if operatorType != projutil.OperatorTypeAnsible && generatePlaybook {
 		return fmt.Errorf("value of --generate-playbook can only be used with --type `ansible`")
 	}
+
+	if len(helmChartRef) != 0 {
+		if operatorType != projutil.OperatorTypeHelm {
+			return fmt.Errorf("value of --helm-chart can only be used with --type=helm")
+		}
+	} else if len(helmChartRepo) != 0 {
+		return fmt.Errorf("value of --helm-chart-repo can only be used with --type=helm and --helm-chart")
+	} else if len(helmChartVersion) != 0 {
+		return fmt.Errorf("value of --helm-chart-version can only be used with --type=helm and --helm-chart")
+	}
+
 	if operatorType == projutil.OperatorTypeGo && (len(apiVersion) != 0 || len(kind) != 0) {
 		return fmt.Errorf("operators of type Go do not use --api-version or --kind")
 	}
 
-	if operatorType != projutil.OperatorTypeGo {
+	// --api-version and --kind are required with --type=ansible and --type=helm, with one exception.
+	//
+	// If --type=helm and --helm-chart is set, --api-version and --kind are optional. If left unset,
+	// sane defaults are used when the specified helm chart is created.
+	if operatorType == projutil.OperatorTypeAnsible || operatorType == projutil.OperatorTypeHelm && len(helmChartRef) == 0 {
 		if len(apiVersion) == 0 {
 			return fmt.Errorf("value of --api-version must not have empty value")
 		}

doc/helm/user-guide.md

@@ -50,6 +50,31 @@ Nginx resource with APIVersion `example.com/v1apha1` and Kind
 To learn more about the project directory structure, see the 
 [project layout][layout_doc] doc.
 
+### Use an existing chart
+
+Instead of creating your project with a boilerplate Helm chart, you can also use `--helm-chart`, `--helm-chart-repo`, and `--helm-chart-version` to use an existing chart, either from your local filesystem or a remote chart repository.
+
+If `--helm-chart` is specified, `--api-version` and `--kind` become optional. If left unset, the SDK will default `--api-version` to `charts.helm.k8s.io/v1alpha1` and will deduce `--kind` from the specified chart.
+
+If `--helm-chart` is a local chart archive or directory, it will be validated and unpacked or copied into the project.
+
+Otherwise, the SDK will attempt to fetch the specified helm chart from a remote repository.
+
+If a custom repository URL is not specified by `--helm-chart-repo`, the following chart reference formats are supported:
+
+- `<repoName>/<chartName>`: Fetch the helm chart named `chartName` from the helm
+                            chart repository named `repoName`, as specified in the
+                            $HELM_HOME/repositories/repositories.yaml file.
+
+- `<url>`: Fetch the helm chart archive at the specified URL.
+
+If a custom repository URL is specified by `--helm-chart-repo`, the only supported format for `--helm-chart` is:
+
+- `<chartName>`: Fetch the helm chart named `chartName` in the helm chart repository
+                 specified by the `--helm-chart-repo` URL.
+
+If `--helm-chart-version` is not set, the SDK will fetch the latest available version of the helm chart. Otherwise, it will fetch the specified version. `--helm-chart-version` is not used when `--helm-chart` itself refers to a specific version, for example when it is a local path or a URL.
+
 ### Operator scope
 
 A namespace-scoped operator (the default) watches and manages resources in a single namespace, whereas a cluster-scoped operator watches and manages resources cluster-wide. Namespace-scoped operators are preferred because of their flexibility. They enable decoupled upgrades, namespace isolation for failures and monitoring, and differing API definitions. However, there are use cases where a cluster-scoped operator may make sense. For example, the [cert-manager](https://github.com/jetstack/cert-manager) operator is often deployed with cluster-scoped permissions and watches so that it can manage issuing certificates for an entire cluster.

doc/sdk-cli-reference.md

@@ -237,28 +237,62 @@ Scaffolds a new operator project.
 * `--kind` string - CRD Kind. (e.g AppService)
 * `--generate-playbook` - Generate a playbook skeleton. (Only used for `--type ansible`)
 * `--cluster-scoped` - Initialize the operator to be cluster-scoped instead of namespace-scoped
+* `--helm-chart` string - Initialize helm operator with existing helm chart (`<URL>`, `<repo>/<name>`, or local path)
+* `--helm-chart-repo` string - Chart repository URL for the requested helm chart
+* `--helm-chart-version` string - Specific version of the helm chart (default is latest version)
 * `-h, --help` - help for new
 
 ### Example
 
-Go project:
+#### Go project
 
 ```console
 $ mkdir $GOPATH/src/github.com/example.com/
 $ cd $GOPATH/src/github.com/example.com/
 $ operator-sdk new app-operator
 ```
 
-Ansible project:
+#### Ansible project
 
 ```console
 $ operator-sdk new app-operator --type=ansible --api-version=app.example.com/v1alpha1 --kind=AppService
 ```
 
-Helm project:
+#### Helm project
+
+For more details about creating new Helm operator projects, see the [Helm user guide][helm-user-guide-create-project].
 
 ```console
-$ operator-sdk new app-operator --type=helm --api-version=app.example.com/v1alpha1 --kind=AppService
+$ operator-sdk new app-operator --type=helm \
+    --api-version=app.example.com/v1alpha1 \
+    --kind=AppService
+
+$ operator-sdk new app-operator --type=helm \
+    --api-version=app.example.com/v1alpha1 \
+    --kind=AppService \
+    --helm-chart=myrepo/app
+
+$ operator-sdk new app-operator --type=helm \
+    --helm-chart=myrepo/app
+
+$ operator-sdk new app-operator --type=helm \
+    --helm-chart=myrepo/app \
+    --helm-chart-version=1.2.3
+
+$ operator-sdk new app-operator --type=helm \
+    --helm-chart=app \
+    --helm-chart-repo=https://charts.mycompany.com/
+
+$ operator-sdk new app-operator --type=helm \
+    --helm-chart=app \
+    --helm-chart-repo=https://charts.mycompany.com/ \
+    --helm-chart-version=1.2.3
+
+$ operator-sdk new app-operator --type=helm \
+    --helm-chart=/path/to/local/chart-directories/app/
+
+$ operator-sdk new app-operator --type=helm \
+    --helm-chart=/path/to/local/chart-archives/app-1.2.3.tgz
 ```
 
 ## add
@@ -524,3 +558,5 @@ $ operator-sdk up local --namespace "testing"
 [utility_link]: https://github.com/operator-framework/operator-sdk/blob/89bf021063d18b6769bdc551ed08fc37027939d5/pkg/util/k8sutil/k8sutil.go#L140
 [k8s-code-generator]: https://github.com/kubernetes/code-generator
 [openapi-code-generator]: https://github.com/kubernetes/kube-openapi
+[helm-user-guide-create-project]: https://github.com/operator-framework/operator-sdk/blob/master/doc/helm/user-guide.md#create-a-new-project
+