Only encoding non-wrapped single .json items as JSON

kyaml/kio/byteio_writer.go

@@ -12,7 +12,7 @@ import (
 	"sigs.k8s.io/kustomize/kyaml/yaml"
 )
 
-// Writer writes ResourceNodes to bytes.
+// ByteWriter writes ResourceNodes to bytes.
 type ByteWriter struct {
 	// Writer is where ResourceNodes are encoded.
 	Writer io.Writer
@@ -55,24 +55,24 @@ func (w ByteWriter) Write(nodes []*yaml.RNode) error {
 		}
 	}
 
-	encoder := yaml.NewEncoder(w.Writer)
-	// keep
-	hasJSONPathExt := make([]bool, len(nodes))
-	defer encoder.Close()
-	for i := range nodes {
-		// Check if the output file is a JSON file so we can force JSON encoding in that case.
-		// YAML flow style encoding may not be compatible because of newlines introduced by the
-		// YAML marshaller in long double quoted string values. These newlines are insignificant
-		// when interpreted as YAML but invalid when interpreted as JSON.
-		if path, _, _ := kioutil.GetFileAnnotations(nodes[i]); path != "" {
+	// Check if the output is a single JSON file so we can force JSON encoding in that case.
+	// YAML flow style encoding may not be compatible because of unquoted strings and newlines
+	// introduced by the YAML marshaller in long string values. These newlines are insignificant
+	// when interpreted as YAML but invalid when interpreted as JSON.
+	jsonEncodeSingleNode := false
+	if w.WrappingKind == "" && len(nodes) == 1 {
+		if path, _, _ := kioutil.GetFileAnnotations(nodes[0]); path != "" {
 			filename := filepath.Base(path)
 			for _, glob := range JSONMatch {
 				if match, _ := filepath.Match(glob, filename); match {
-					hasJSONPathExt[i] = true
+					jsonEncodeSingleNode = true
 					break
 				}
 			}
 		}
+	}
+
+	for i := range nodes {
 		// clean resources by removing annotations set by the Reader
 		if !w.KeepReaderAnnotations {
 			_, err := nodes[i].Pipe(yaml.ClearAnnotation(kioutil.IndexAnnotation))
@@ -96,10 +96,18 @@ func (w ByteWriter) Write(nodes []*yaml.RNode) error {
 		}
 	}
 
+	if jsonEncodeSingleNode {
+		encoder := json.NewEncoder(w.Writer)
+		encoder.SetIndent("", "  ")
+		return errors.Wrap(encoder.Encode(nodes[0]))
+	}
+
+	encoder := yaml.NewEncoder(w.Writer)
+	defer encoder.Close()
 	// don't wrap the elements
 	if w.WrappingKind == "" {
 		for i := range nodes {
-			if err := w.encode(encoder, hasJSONPathExt[i], nodes[i].Document()); err != nil {
+			if err := encoder.Encode(nodes[i].Document()); err != nil {
 				return err
 			}
 		}
@@ -133,27 +141,7 @@ func (w ByteWriter) Write(nodes []*yaml.RNode) error {
 	for i := range nodes {
 		items.Content = append(items.Content, nodes[i].YNode())
 	}
-	err := w.encode(encoder, false, doc)
+	err := encoder.Encode(doc)
 	yaml.UndoSerializationHacksOnNodes(nodes)
 	return err
 }
-
-// encode encodes the input document node to appropriate node format
-func (w ByteWriter) encode(encoder *yaml.Encoder, forceJSON bool, doc *yaml.Node) error {
-	rNode := &yaml.RNode{}
-	rNode.SetYNode(doc)
-	useJSONEncoder := forceJSON
-	if !forceJSON {
-		str, err := rNode.String()
-		if err != nil {
-			return errors.Wrap(err)
-		}
-		useJSONEncoder = json.Valid([]byte(str))
-	}
-	if useJSONEncoder {
-		je := json.NewEncoder(w.Writer)
-		je.SetIndent("", "  ")
-		return errors.Wrap(je.Encode(rNode))
-	}
-	return encoder.Encode(doc)
-}

kyaml/kio/byteio_writer_test.go

@@ -198,9 +198,9 @@ metadata:
 			items: []string{
 				`{
   "a": "a long string that would certainly see a newline introduced by the YAML marshaller abcd123",
-  "metadata": {
-    "annotations": {
-      "config.kubernetes.io/path": "test.json"
+  metadata: {
+    annotations: {
+      config.kubernetes.io/path: test.json
     }
   }
 }`,
@@ -215,6 +215,65 @@ metadata:
   }
 }`,
 		},
+
+		//
+		// Test Case
+		//
+		{
+			name:     "encode_wrapped_json_as_yaml",
+			instance: ByteWriter{
+				Sort:               true,
+				WrappingKind:       ResourceListKind,
+				WrappingAPIVersion: ResourceListAPIVersion,
+			},
+			items: []string{
+				`{
+  "a": "b",
+  "metadata": {
+    "annotations": {
+      "config.kubernetes.io/path": "test.json"
+    }
+  }
+}`,
+			},
+
+			expectedOutput: `apiVersion: config.kubernetes.io/v1alpha1
+kind: ResourceList
+items:
+- {"a": "b", "metadata": {"annotations": {"config.kubernetes.io/path": "test.json"}}}
+`,
+		},
+
+		//
+		// Test Case
+		//
+		{
+			name:     "encode_multi_doc_json_as_yaml",
+			items: []string{
+				`{
+  "a": "b",
+  "metadata": {
+    "annotations": {
+      "config.kubernetes.io/path": "test-1.json"
+    }
+  }
+}`,
+				`{
+  "c": "d",
+  "metadata": {
+    "annotations": {
+      "config.kubernetes.io/path": "test-2.json"
+    }
+  }
+}`,
+			},
+
+			expectedOutput: `
+{"a": "b", "metadata": {"annotations": {"config.kubernetes.io/path": "test-1.json"}}}
+---
+{"c": "d", "metadata": {"annotations": {"config.kubernetes.io/path": "test-2.json"}}}
+`,
+		},
 	}
 
 	for i := range testCases {