Merge pull request #2480 from mortent/FormattingAnnotation

Add annotation for opting out of formatting

kyaml/kio/filters/fmtr.go

@@ -31,6 +31,20 @@ import (
 	"sigs.k8s.io/kustomize/kyaml/yaml"
 )
 
+type FormattingStrategy = string
+
+const (
+	// NoFmtAnnotation determines if the resource should be formatted.
+	FmtAnnotation string = "config.kubernetes.io/formatting"
+
+	// FmtStrategyStandard means the resource will be formatted according
+	// to the default rules.
+	FmtStrategyStandard FormattingStrategy = "standard"
+
+	// FmtStrategyNone means the resource will not be formatted.
+	FmtStrategyNone FormattingStrategy = "none"
+)
+
 // FormatInput returns the formatted input.
 func FormatInput(input io.Reader) (*bytes.Buffer, error) {
 	buff := &bytes.Buffer{}
@@ -64,6 +78,15 @@ var _ kio.Filter = FormatFilter{}
 
 func (f FormatFilter) Filter(slice []*yaml.RNode) ([]*yaml.RNode, error) {
 	for i := range slice {
+		fmtStrategy, err := getFormattingStrategy(slice[i])
+		if err != nil {
+			return nil, err
+		}
+
+		if fmtStrategy == FmtStrategyNone {
+			continue
+		}
+
 		kindNode, err := slice[i].Pipe(yaml.Get("kind"))
 		if err != nil {
 			return nil, err
@@ -94,6 +117,28 @@ func (f FormatFilter) Filter(slice []*yaml.RNode) ([]*yaml.RNode, error) {
 	return slice, nil
 }
 
+// getFormattingStrategy looks for the formatting annotation to determine
+// which strategy should be used for formatting. The default is standard
+// if no annotation is found.
+func getFormattingStrategy(node *yaml.RNode) (FormattingStrategy, error) {
+	value, err := node.Pipe(yaml.GetAnnotation(FmtAnnotation))
+	if err != nil || value == nil {
+		return FmtStrategyStandard, err
+	}
+
+	fmtStrategy := value.YNode().Value
+
+	switch fmtStrategy {
+	case FmtStrategyStandard:
+		return FmtStrategyStandard, nil
+	case FmtStrategyNone:
+		return FmtStrategyNone, nil
+	default:
+		return "", fmt.Errorf(
+			"formatting annotation has illegal value %s", fmtStrategy)
+	}
+}
+
 type formatter struct {
 	apiVersion string
 	kind       string

kyaml/kio/filters/fmtr_test.go

@@ -904,3 +904,118 @@ func TestFormatFileOrDirectory_trimWhiteSpace(t *testing.T) {
 
 	assert.Equal(t, string(testyaml.FormattedYaml1), string(b))
 }
+
+func TestFormatFileOrDirectory_FmtAnnotation(t *testing.T) {
+	testCases := []struct {
+		name           string
+		input          []byte
+		expectedOutput []byte
+		expectError    bool
+	}{
+		{
+			name:           "no formatting annotation",
+			input:          testyaml.UnformattedYaml1,
+			expectedOutput: testyaml.FormattedYaml1,
+		},
+		{
+			name: "formatting strategy none",
+			input: []byte(`
+spec: a
+status:
+  conditions:
+  - 3
+  - 1
+  - 2
+apiVersion: example.com/v1beta1
+kind: MyType
+metadata:
+  annotations:
+    config.kubernetes.io/formatting: none
+`),
+			expectedOutput: []byte(`
+spec: a
+status:
+  conditions:
+  - 3
+  - 1
+  - 2
+apiVersion: example.com/v1beta1
+kind: MyType
+metadata:
+  annotations:
+    config.kubernetes.io/formatting: none
+`),
+		},
+		{
+			name: "formatting strategy standard",
+			input: []byte(`
+spec: a
+status:
+  conditions:
+  - 3
+  - 1
+  - 2
+apiVersion: example.com/v1beta1
+kind: MyType
+metadata:
+  annotations:
+    config.kubernetes.io/formatting: standard
+`),
+			expectedOutput: []byte(`
+apiVersion: example.com/v1beta1
+kind: MyType
+metadata:
+  annotations:
+    config.kubernetes.io/formatting: standard
+spec: a
+status:
+  conditions:
+  - 3
+  - 1
+  - 2
+`),
+		},
+		{
+			name: "unknown formatting strategy",
+			input: []byte(`
+spec: a
+status:
+  conditions:
+  - 3
+  - 1
+  - 2
+apiVersion: example.com/v1beta1
+kind: MyType
+metadata:
+  annotations:
+    config.kubernetes.io/formatting: unknown
+`),
+			expectError: true,
+		},
+	}
+
+	for i := range testCases {
+		test := testCases[i]
+		t.Run(test.name, func(t *testing.T) {
+			f, err := ioutil.TempFile("", "yamlfmt*.yaml")
+			assert.NoError(t, err)
+			defer os.Remove(f.Name())
+
+			err = ioutil.WriteFile(f.Name(), test.input, 0600)
+			assert.NoError(t, err)
+
+			err = FormatFileOrDirectory(f.Name())
+			if test.expectError {
+				assert.Error(t, err)
+				return
+			}
+			assert.NoError(t, err)
+
+			b, err := ioutil.ReadFile(f.Name())
+			assert.NoError(t, err)
+
+			assert.Equal(t, strings.TrimSpace(string(test.expectedOutput)),
+				strings.TrimSpace(string(b)))
+		})
+	}
+}

kyaml/testutil/testutil.go

@@ -0,0 +1,33 @@
+package testutil_test
+
+import (
+	"bytes"
+
+	"sigs.k8s.io/kustomize/kyaml/kio"
+	"sigs.k8s.io/kustomize/kyaml/yaml"
+)
+
+func UpdateYamlString(doc string, functions ...yaml.Filter) (string, error) {
+	b, err := UpdateYamlBytes([]byte(doc), functions...)
+	return string(b), err
+}
+
+func UpdateYamlBytes(b []byte, function ...yaml.Filter) ([]byte, error) {
+	var out bytes.Buffer
+	rw := kio.ByteReadWriter{
+		Reader: bytes.NewBuffer(b),
+		Writer: &out,
+	}
+	err := kio.Pipeline{
+		Inputs: []kio.Reader{&rw},
+		Filters: []kio.Filter{
+			kio.FilterAll(yaml.FilterFunc(
+				func(node *yaml.RNode) (*yaml.RNode, error) {
+					return node.Pipe(function...)
+				}),
+			),
+		},
+		Outputs: []kio.Writer{&rw},
+	}.Execute()
+	return out.Bytes(), err
+}