feat: add crd resource visitor util (#804)

pkg/cmd/util/resource/crd/multi_crd.yaml

@@ -0,0 +1,51 @@
+
+---
+apiVersion: apiextensions.k8s.io/v1beta1
+kind: CustomResourceDefinition
+metadata:
+  annotations:
+    controller-gen.kubebuilder.io/version: v0.2.4
+  creationTimestamp: null
+  name: guests.webapp.my.domain
+spec:
+  group: webapp.my.domain
+  names:
+    kind: Guest
+    listKind: GuestList
+    plural: guests
+    singular: guest
+  scope: Namespaced
+  validation:
+    openAPIV3Schema:
+      description: Guest is the Schema for the guests API
+      properties:
+        apiVersion:
+          description: 'APIVersion defines the versioned schema of this representation of an object. Servers should convert recognized schemas to the latest internal value, and may reject unrecognized values. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources'
+          type: string
+        kind:
+          description: 'Kind is a string value representing the REST resource this object represents. Servers may infer this from the endpoint the client submits requests to. Cannot be updated. In CamelCase. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds'
+          type: string
+        metadata:
+          type: object
+        spec:
+          description: GuestSpec defines the desired state of Guest
+          properties:
+            beep:
+              description: Beep is an example field of Guest. Edit Guest_types.go to remove/update
+              type: string
+          type: object
+        status:
+          description: GuestStatus defines the observed state of Guest
+          type: object
+      type: object
+  version: v1
+  versions:
+    - name: v1
+      served: true
+      storage: true
+status:
+  acceptedNames:
+    kind: ""
+    plural: ""
+  conditions: []
+  storedVersions: []

pkg/cmd/util/resource/crd/webapp_crd.yaml

@@ -0,0 +1,49 @@
+apiVersion: apiextensions.k8s.io/v1beta1
+kind: CustomResourceDefinition
+metadata:
+  annotations:
+    controller-gen.kubebuilder.io/version: v0.2.4
+  creationTimestamp: null
+  name: guestbooks.webapp.my.domain
+spec:
+  group: webapp.my.domain
+  names:
+    kind: Guestbook
+    listKind: GuestbookList
+    plural: guestbooks
+    singular: guestbook
+  scope: Namespaced
+  validation:
+    openAPIV3Schema:
+      description: Guestbook is the Schema for the guestbooks API
+      properties:
+        apiVersion:
+          description: 'APIVersion defines the versioned schema of this representation of an object. Servers should convert recognized schemas to the latest internal value, and may reject unrecognized values. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources'
+          type: string
+        kind:
+          description: 'Kind is a string value representing the REST resource this object represents. Servers may infer this from the endpoint the client submits requests to. Cannot be updated. In CamelCase. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds'
+          type: string
+        metadata:
+          type: object
+        spec:
+          description: GuestbookSpec defines the desired state of Guestbook
+          properties:
+            foo:
+              description: Foo is an example field of Guestbook. Edit Guestbook_types.go to remove/update
+              type: string
+          type: object
+        status:
+          description: GuestbookStatus defines the observed state of Guestbook
+          type: object
+      type: object
+  version: v1
+  versions:
+    - name: v1
+      served: true
+      storage: true
+status:
+  acceptedNames:
+    kind: ""
+    plural: ""
+  conditions: []
+  storedVersions: []

pkg/cmd/util/resource/visitor.go

@@ -0,0 +1,64 @@
+package resource
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+
+	"k8s.io/apimachinery/pkg/util/yaml"
+)
+
+var FileExtensions = []string{".yaml", ".yml"}
+
+type CrdVisitor struct {
+	Path string
+}
+
+// Visit walks a list of resources under target path.
+func (v *CrdVisitor) Visit() (objs []map[string]interface{}, err error) {
+	err = filepath.WalkDir(v.Path, func(filePath string, d os.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+
+		// check file extension
+		if ignoreFile(filePath, FileExtensions) {
+			return nil
+		}
+
+		f, err := os.Open(filePath)
+		if err != nil {
+			return err
+		}
+		decoder := yaml.NewYAMLOrJSONDecoder(f, 4096)
+		for {
+			data := make(map[string]interface{})
+			if err := decoder.Decode(&data); err != nil {
+				if err == io.EOF {
+					return nil
+				}
+				return fmt.Errorf("error parsing %s: %v", filePath, err)
+			}
+			if len(data) == 0 {
+				continue
+			}
+
+			objs = append(objs, data)
+		}
+	})
+	return objs, err
+}
+
+func ignoreFile(path string, extensions []string) bool {
+	if len(extensions) == 0 {
+		return false
+	}
+	ext := filepath.Ext(path)
+	for _, s := range extensions {
+		if s == ext {
+			return false
+		}
+	}
+	return true
+}

pkg/cmd/util/resource/visitor_test.go

@@ -0,0 +1,18 @@
+package resource
+
+import (
+	"testing"
+)
+
+func TestCrdVisitor(t *testing.T) {
+	visitor := CrdVisitor{
+		Path: "./crd",
+	}
+	objs, err := visitor.Visit()
+	if err != nil {
+		t.Errorf("unexpected err: %v", err)
+	}
+	if len(objs) != 2 {
+		t.Errorf("unexpected doc size: %d", len(objs))
+	}
+}