Lint the `crds/` directory.

This checks that the `crds/` dir only contains YAML files that define
K8s resources with `kind: CustomResourceDefinition`.

Checking that the YAML files are not templates will be done in a
separate commit.

Signed-off-by: Zach Burgess <zachburg@google.com>

pkg/lint/lint.go

@@ -60,6 +60,7 @@ func RunAll(baseDir string, values map[string]interface{}, namespace string, opt
 	rules.ValuesWithOverrides(&result, values)
 	rules.TemplatesWithSkipSchemaValidation(&result, values, namespace, lo.KubeVersion, lo.SkipSchemaValidation)
 	rules.Dependencies(&result)
+	rules.Crds(&result)
 
 	return result
 }

pkg/lint/lint_test.go

@@ -32,6 +32,7 @@ const namespace = "testNamespace"
 const badChartDir = "rules/testdata/badchartfile"
 const badValuesFileDir = "rules/testdata/badvaluesfile"
 const badYamlFileDir = "rules/testdata/albatross"
+const badCrdFileDir = "rules/testdata/badcrdfile"
 const goodChartDir = "rules/testdata/goodone"
 const subChartValuesDir = "rules/testdata/withsubchart"
 const malformedTemplate = "rules/testdata/malformed-template"
@@ -111,6 +112,16 @@ func TestBadValues(t *testing.T) {
 	}
 }
 
+func TestBadCrdFile(t *testing.T) {
+	m := RunAll(badCrdFileDir, values, namespace).Messages
+	if len(m) < 1 {
+		t.Fatalf("All didn't fail with expected errors, got %#v", m)
+	}
+	if !strings.Contains(m[0].Err.Error(), "object kind is not 'CustomResourceDefinition'") {
+		t.Errorf("All didn't have the error for invalid CRD: %s", m[0].Err)
+	}
+}
+
 func TestGoodChart(t *testing.T) {
 	m := RunAll(goodChartDir, values, namespace).Messages
 	if len(m) != 0 {

pkg/lint/rules/crds.go

@@ -0,0 +1,96 @@
+/*
+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 rules
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+
+	"k8s.io/apimachinery/pkg/util/yaml"
+
+	"helm.sh/helm/v4/pkg/chart/v2/loader"
+	"helm.sh/helm/v4/pkg/lint/support"
+)
+
+// Crds lints the CRDs in the Linter.
+func Crds(linter *support.Linter) {
+	fpath := "crds/"
+	crdsPath := filepath.Join(linter.ChartDir, fpath)
+
+	crdsDirExist := linter.RunLinterRule(support.WarningSev, fpath, validateCrdsDir(crdsPath))
+
+	// crds directory is optional
+	if !crdsDirExist {
+		return
+	}
+
+	// Load chart and parse CRDs
+	chart, err := loader.Load(linter.ChartDir)
+
+	chartLoaded := linter.RunLinterRule(support.ErrorSev, fpath, err)
+
+	if !chartLoaded {
+		return
+	}
+
+	/* Iterate over all the CRDs to check:
+	- It is a YAML file
+	- The kind is CustomResourceDefinition
+	*/
+	for _, crd := range chart.CRDObjects() {
+		fileName := crd.Name
+		fpath = fileName
+
+		decoder := yaml.NewYAMLOrJSONDecoder(bytes.NewReader(crd.File.Data), 4096)
+		for {
+			var yamlStruct *K8sYamlStruct
+
+			err := decoder.Decode(&yamlStruct)
+			if err == io.EOF {
+				break
+			}
+
+			// If YAML linting fails here, it will always fail in the next block as well, so we should return here.
+			if !linter.RunLinterRule(support.ErrorSev, fpath, validateYamlContent(err)) {
+				return
+			}
+
+			linter.RunLinterRule(support.ErrorSev, fpath, validateCrdKind(yamlStruct))
+		}
+	}
+}
+
+// Validation functions
+func validateCrdsDir(crdsPath string) error {
+	if fi, err := os.Stat(crdsPath); err == nil {
+		if !fi.IsDir() {
+			return errors.New("not a directory")
+		}
+	}
+	return nil
+}
+
+func validateCrdKind(obj *K8sYamlStruct) error {
+	if obj.Kind != "CustomResourceDefinition" {
+		return fmt.Errorf("object kind is not 'CustomResourceDefinition'")
+	}
+	return nil
+}

pkg/lint/rules/crds_test.go

@@ -0,0 +1,51 @@
+/*
+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 rules
+
+import (
+	"strings"
+	"testing"
+
+	"helm.sh/helm/v4/pkg/lint/support"
+)
+
+const crdsTestBasedir = "./testdata/withcrd"
+const invalidCrdsDir = "./testdata/invalidcrdsdir"
+
+func TestCrdsDir(t *testing.T) {
+	linter := support.Linter{ChartDir: crdsTestBasedir}
+	Crds(&linter)
+	res := linter.Messages
+
+	if len(res) > 0 {
+		t.Fatalf("Expected no errors, got %d, %v", len(res), res)
+	}
+}
+
+func TestInvalidCrdsDir(t *testing.T) {
+	linter := support.Linter{ChartDir: invalidCrdsDir}
+	Crds(&linter)
+	res := linter.Messages
+
+	if len(res) != 1 {
+		t.Fatalf("Expected one error, got %d, %v", len(res), res)
+	}
+
+	if !strings.Contains(res[0].Err.Error(), "not a directory") {
+		t.Errorf("Unexpected error: %s", res[0])
+	}
+}

pkg/lint/rules/testdata/badcrdfile/Chart.yaml

@@ -0,0 +1,6 @@
+apiVersion: v2
+description: A Helm chart for Kubernetes
+version: 0.1.0
+name: badcrdfile
+type: application
+icon: http://riverrun.io

pkg/lint/rules/testdata/badcrdfile/crds/bad-crd.yaml

@@ -0,0 +1,2 @@
+apiVersion: apiextensions.k8s.io/v1beta1
+kind: NotACustomResourceDefinition

pkg/lint/rules/testdata/badcrdfile/values.yaml

@@ -0,0 +1 @@
+# Default values for badcrdfile.

pkg/lint/rules/testdata/invalidcrdsdir/Chart.yaml

@@ -0,0 +1,6 @@
+apiVersion: v2
+description: A Helm chart for Kubernetes
+version: 0.1.0
+name: invalidcrdsdir
+type: application
+icon: http://riverrun.io

pkg/lint/rules/testdata/invalidcrdsdir/values.yaml

@@ -0,0 +1 @@
+# Default values for badcrdfile.

pkg/lint/rules/testdata/withcrd/Chart.yaml

@@ -0,0 +1,5 @@
+apiVersion: v1
+name: withcrd
+description: testing chart with a CRD
+version: 199.44.12345-Alpha.1+cafe009
+icon: http://riverrun.io

pkg/lint/rules/testdata/withcrd/crds/test-crd.yaml

@@ -0,0 +1,19 @@
+apiVersion: apiextensions.k8s.io/v1beta1
+kind: CustomResourceDefinition
+metadata:
+  name: tests.test.io
+spec:
+  group: test.io
+  names:
+    kind: Test
+    listKind: TestList
+    plural: tests
+    singular: test
+  scope: Namespaced
+  versions:
+    - name : v1alpha2
+      served: true
+      storage: true
+    - name : v1alpha1
+      served: true
+      storage: false