Adding upstream version 1.1.0.upstream/1.1.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1625 insertions, 0 deletions

diff --git a/dependencies/pkg/mod/github.com/goccy/go-yaml@v1.9.6/decode.go b/dependencies/pkg/mod/github.com/goccy/go-yaml@v1.9.6/decode.go
new file mode 100644
index 0000000..8cd7d85
--- /dev/null
+++ b/dependencies/pkg/mod/github.com/goccy/go-yaml@v1.9.6/decode.go
@@ -0,0 +1,1625 @@
+package yaml
+
+import (
+	"bytes"
+	"context"
+	"encoding"
+	"encoding/base64"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"math"
+	"os"
+	"path/filepath"
+	"reflect"
+	"strconv"
+	"time"
+
+	"github.com/goccy/go-yaml/ast"
+	"github.com/goccy/go-yaml/internal/errors"
+	"github.com/goccy/go-yaml/parser"
+	"github.com/goccy/go-yaml/token"
+	"golang.org/x/xerrors"
+)
+
+// Decoder reads and decodes YAML values from an input stream.
+type Decoder struct {
+	reader               io.Reader
+	referenceReaders     []io.Reader
+	anchorNodeMap        map[string]ast.Node
+	anchorValueMap       map[string]reflect.Value
+	toCommentMap         CommentMap
+	opts                 []DecodeOption
+	referenceFiles       []string
+	referenceDirs        []string
+	isRecursiveDir       bool
+	isResolvedReference  bool
+	validator            StructValidator
+	disallowUnknownField bool
+	disallowDuplicateKey bool
+	useOrderedMap        bool
+	useJSONUnmarshaler   bool
+	parsedFile           *ast.File
+	streamIndex          int
+}
+
+// NewDecoder returns a new decoder that reads from r.
+func NewDecoder(r io.Reader, opts ...DecodeOption) *Decoder {
+	return &Decoder{
+		reader:               r,
+		anchorNodeMap:        map[string]ast.Node{},
+		anchorValueMap:       map[string]reflect.Value{},
+		opts:                 opts,
+		referenceReaders:     []io.Reader{},
+		referenceFiles:       []string{},
+		referenceDirs:        []string{},
+		isRecursiveDir:       false,
+		isResolvedReference:  false,
+		disallowUnknownField: false,
+		disallowDuplicateKey: false,
+		useOrderedMap:        false,
+	}
+}
+
+func (d *Decoder) castToFloat(v interface{}) interface{} {
+	switch vv := v.(type) {
+	case int:
+		return float64(vv)
+	case int8:
+		return float64(vv)
+	case int16:
+		return float64(vv)
+	case int32:
+		return float64(vv)
+	case int64:
+		return float64(vv)
+	case uint:
+		return float64(vv)
+	case uint8:
+		return float64(vv)
+	case uint16:
+		return float64(vv)
+	case uint32:
+		return float64(vv)
+	case uint64:
+		return float64(vv)
+	case float32:
+		return float64(vv)
+	case float64:
+		return vv
+	case string:
+		// if error occurred, return zero value
+		f, _ := strconv.ParseFloat(vv, 64)
+		return f
+	}
+	return 0
+}
+
+func (d *Decoder) mergeValueNode(value ast.Node) ast.Node {
+	if value.Type() == ast.AliasType {
+		aliasNode := value.(*ast.AliasNode)
+		aliasName := aliasNode.Value.GetToken().Value
+		return d.anchorNodeMap[aliasName]
+	}
+	return value
+}
+
+func (d *Decoder) mapKeyNodeToString(node ast.MapKeyNode) string {
+	key := d.nodeToValue(node)
+	if key == nil {
+		return "null"
+	}
+	if k, ok := key.(string); ok {
+		return k
+	}
+	return fmt.Sprint(key)
+}
+
+func (d *Decoder) setToMapValue(node ast.Node, m map[string]interface{}) {
+	d.setPathToCommentMap(node)
+	switch n := node.(type) {
+	case *ast.MappingValueNode:
+		if n.Key.Type() == ast.MergeKeyType {
+			d.setToMapValue(d.mergeValueNode(n.Value), m)
+		} else {
+			key := d.mapKeyNodeToString(n.Key)
+			m[key] = d.nodeToValue(n.Value)
+		}
+	case *ast.MappingNode:
+		for _, value := range n.Values {
+			d.setToMapValue(value, m)
+		}
+	case *ast.AnchorNode:
+		anchorName := n.Name.GetToken().Value
+		d.anchorNodeMap[anchorName] = n.Value
+	}
+}
+
+func (d *Decoder) setToOrderedMapValue(node ast.Node, m *MapSlice) {
+	switch n := node.(type) {
+	case *ast.MappingValueNode:
+		if n.Key.Type() == ast.MergeKeyType {
+			d.setToOrderedMapValue(d.mergeValueNode(n.Value), m)
+		} else {
+			key := d.mapKeyNodeToString(n.Key)
+			*m = append(*m, MapItem{Key: key, Value: d.nodeToValue(n.Value)})
+		}
+	case *ast.MappingNode:
+		for _, value := range n.Values {
+			d.setToOrderedMapValue(value, m)
+		}
+	}
+}
+
+func (d *Decoder) setPathToCommentMap(node ast.Node) {
+	if d.toCommentMap == nil {
+		return
+	}
+	commentGroup := node.GetComment()
+	if commentGroup == nil {
+		return
+	}
+	texts := []string{}
+	for _, comment := range commentGroup.Comments {
+		texts = append(texts, comment.Token.Value)
+	}
+	if len(texts) == 0 {
+		return
+	}
+	if len(texts) == 1 {
+		d.toCommentMap[node.GetPath()] = LineComment(texts[0])
+	} else {
+		d.toCommentMap[node.GetPath()] = HeadComment(texts...)
+	}
+}
+
+func (d *Decoder) nodeToValue(node ast.Node) interface{} {
+	d.setPathToCommentMap(node)
+	switch n := node.(type) {
+	case *ast.NullNode:
+		return nil
+	case *ast.StringNode:
+		return n.GetValue()
+	case *ast.IntegerNode:
+		return n.GetValue()
+	case *ast.FloatNode:
+		return n.GetValue()
+	case *ast.BoolNode:
+		return n.GetValue()
+	case *ast.InfinityNode:
+		return n.GetValue()
+	case *ast.NanNode:
+		return n.GetValue()
+	case *ast.TagNode:
+		switch token.ReservedTagKeyword(n.Start.Value) {
+		case token.TimestampTag:
+			t, _ := d.castToTime(n.Value)
+			return t
+		case token.IntegerTag:
+			i, _ := strconv.Atoi(fmt.Sprint(d.nodeToValue(n.Value)))
+			return i
+		case token.FloatTag:
+			return d.castToFloat(d.nodeToValue(n.Value))
+		case token.NullTag:
+			return nil
+		case token.BinaryTag:
+			b, _ := base64.StdEncoding.DecodeString(d.nodeToValue(n.Value).(string))
+			return b
+		case token.StringTag:
+			return d.nodeToValue(n.Value)
+		case token.MappingTag:
+			return d.nodeToValue(n.Value)
+		}
+	case *ast.AnchorNode:
+		anchorName := n.Name.GetToken().Value
+		anchorValue := d.nodeToValue(n.Value)
+		d.anchorNodeMap[anchorName] = n.Value
+		return anchorValue
+	case *ast.AliasNode:
+		aliasName := n.Value.GetToken().Value
+		node := d.anchorNodeMap[aliasName]
+		return d.nodeToValue(node)
+	case *ast.LiteralNode:
+		return n.Value.GetValue()
+	case *ast.MappingKeyNode:
+		return d.nodeToValue(n.Value)
+	case *ast.MappingValueNode:
+		if n.Key.Type() == ast.MergeKeyType {
+			value := d.mergeValueNode(n.Value)
+			if d.useOrderedMap {
+				m := MapSlice{}
+				d.setToOrderedMapValue(value, &m)
+				return m
+			}
+			m := map[string]interface{}{}
+			d.setToMapValue(value, m)
+			return m
+		}
+		key := d.mapKeyNodeToString(n.Key)
+		if d.useOrderedMap {
+			return MapSlice{{Key: key, Value: d.nodeToValue(n.Value)}}
+		}
+		return map[string]interface{}{
+			key: d.nodeToValue(n.Value),
+		}
+	case *ast.MappingNode:
+		if d.useOrderedMap {
+			m := make(MapSlice, 0, len(n.Values))
+			for _, value := range n.Values {
+				d.setToOrderedMapValue(value, &m)
+			}
+			return m
+		}
+		m := make(map[string]interface{}, len(n.Values))
+		for _, value := range n.Values {
+			d.setToMapValue(value, m)
+		}
+		return m
+	case *ast.SequenceNode:
+		v := make([]interface{}, 0, len(n.Values))
+		for _, value := range n.Values {
+			v = append(v, d.nodeToValue(value))
+		}
+		return v
+	}
+	return nil
+}
+
+func (d *Decoder) resolveAlias(node ast.Node) (ast.Node, error) {
+	switch n := node.(type) {
+	case *ast.MappingNode:
+		for idx, v := range n.Values {
+			value, err := d.resolveAlias(v)
+			if err != nil {
+				return nil, err
+			}
+			n.Values[idx] = value.(*ast.MappingValueNode)
+		}
+	case *ast.TagNode:
+		value, err := d.resolveAlias(n.Value)
+		if err != nil {
+			return nil, err
+		}
+		n.Value = value
+	case *ast.MappingKeyNode:
+		value, err := d.resolveAlias(n.Value)
+		if err != nil {
+			return nil, err
+		}
+		n.Value = value
+	case *ast.MappingValueNode:
+		if n.Key.Type() == ast.MergeKeyType && n.Value.Type() == ast.AliasType {
+			value, err := d.resolveAlias(n.Value)
+			if err != nil {
+				return nil, err
+			}
+			keyColumn := n.Key.GetToken().Position.Column
+			requiredColumn := keyColumn + 2
+			value.AddColumn(requiredColumn)
+			n.Value = value
+		} else {
+			key, err := d.resolveAlias(n.Key)
+			if err != nil {
+				return nil, err
+			}
+			n.Key = key.(ast.MapKeyNode)
+			value, err := d.resolveAlias(n.Value)
+			if err != nil {
+				return nil, err
+			}
+			n.Value = value
+		}
+	case *ast.SequenceNode:
+		for idx, v := range n.Values {
+			value, err := d.resolveAlias(v)
+			if err != nil {
+				return nil, err
+			}
+			n.Values[idx] = value
+		}
+	case *ast.AliasNode:
+		aliasName := n.Value.GetToken().Value
+		node := d.anchorNodeMap[aliasName]
+		if node == nil {
+			return nil, xerrors.Errorf("cannot find anchor by alias name %s", aliasName)
+		}
+		return d.resolveAlias(node)
+	}
+	return node, nil
+}
+
+func (d *Decoder) getMapNode(node ast.Node) (ast.MapNode, error) {
+	if _, ok := node.(*ast.NullNode); ok {
+		return nil, nil
+	}
+	if anchor, ok := node.(*ast.AnchorNode); ok {
+		mapNode, ok := anchor.Value.(ast.MapNode)
+		if ok {
+			return mapNode, nil
+		}
+		return nil, errUnexpectedNodeType(anchor.Value.Type(), ast.MappingType, node.GetToken())
+	}
+	if alias, ok := node.(*ast.AliasNode); ok {
+		aliasName := alias.Value.GetToken().Value
+		node := d.anchorNodeMap[aliasName]
+		if node == nil {
+			return nil, xerrors.Errorf("cannot find anchor by alias name %s", aliasName)
+		}
+		mapNode, ok := node.(ast.MapNode)
+		if ok {
+			return mapNode, nil
+		}
+		return nil, errUnexpectedNodeType(node.Type(), ast.MappingType, node.GetToken())
+	}
+	mapNode, ok := node.(ast.MapNode)
+	if !ok {
+		return nil, errUnexpectedNodeType(node.Type(), ast.MappingType, node.GetToken())
+	}
+	return mapNode, nil
+}
+
+func (d *Decoder) getArrayNode(node ast.Node) (ast.ArrayNode, error) {
+	if _, ok := node.(*ast.NullNode); ok {
+		return nil, nil
+	}
+	if anchor, ok := node.(*ast.AnchorNode); ok {
+		arrayNode, ok := anchor.Value.(ast.ArrayNode)
+		if ok {
+			return arrayNode, nil
+		}
+
+		return nil, errUnexpectedNodeType(anchor.Value.Type(), ast.SequenceType, node.GetToken())
+	}
+	if alias, ok := node.(*ast.AliasNode); ok {
+		aliasName := alias.Value.GetToken().Value
+		node := d.anchorNodeMap[aliasName]
+		if node == nil {
+			return nil, xerrors.Errorf("cannot find anchor by alias name %s", aliasName)
+		}
+		arrayNode, ok := node.(ast.ArrayNode)
+		if ok {
+			return arrayNode, nil
+		}
+		return nil, errUnexpectedNodeType(node.Type(), ast.SequenceType, node.GetToken())
+	}
+	arrayNode, ok := node.(ast.ArrayNode)
+	if !ok {
+		return nil, errUnexpectedNodeType(node.Type(), ast.SequenceType, node.GetToken())
+	}
+	return arrayNode, nil
+}
+
+func (d *Decoder) fileToNode(f *ast.File) ast.Node {
+	for _, doc := range f.Docs {
+		if v := d.nodeToValue(doc.Body); v != nil {
+			return doc.Body
+		}
+	}
+	return nil
+}
+
+func (d *Decoder) convertValue(v reflect.Value, typ reflect.Type, src ast.Node) (reflect.Value, error) {
+	if typ.Kind() != reflect.String {
+		if !v.Type().ConvertibleTo(typ) {
+			return reflect.Zero(typ), errTypeMismatch(typ, v.Type(), src.GetToken())
+		}
+		return v.Convert(typ), nil
+	}
+	// cast value to string
+	switch v.Type().Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return reflect.ValueOf(fmt.Sprint(v.Int())), nil
+	case reflect.Float32, reflect.Float64:
+		return reflect.ValueOf(fmt.Sprint(v.Float())), nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return reflect.ValueOf(fmt.Sprint(v.Uint())), nil
+	case reflect.Bool:
+		return reflect.ValueOf(fmt.Sprint(v.Bool())), nil
+	}
+	if !v.Type().ConvertibleTo(typ) {
+		return reflect.Zero(typ), errTypeMismatch(typ, v.Type(), src.GetToken())
+	}
+	return v.Convert(typ), nil
+}
+
+type overflowError struct {
+	dstType reflect.Type
+	srcNum  string
+}
+
+func (e *overflowError) Error() string {
+	return fmt.Sprintf("cannot unmarshal %s into Go value of type %s ( overflow )", e.srcNum, e.dstType)
+}
+
+func errOverflow(dstType reflect.Type, num string) *overflowError {
+	return &overflowError{dstType: dstType, srcNum: num}
+}
+
+func errTypeMismatch(dstType, srcType reflect.Type, token *token.Token) *errors.TypeError {
+	return &errors.TypeError{DstType: dstType, SrcType: srcType, Token: token}
+}
+
+type unknownFieldError struct {
+	err error
+}
+
+func (e *unknownFieldError) Error() string {
+	return e.err.Error()
+}
+
+func errUnknownField(msg string, tk *token.Token) *unknownFieldError {
+	return &unknownFieldError{err: errors.ErrSyntax(msg, tk)}
+}
+
+func errUnexpectedNodeType(actual, expected ast.NodeType, tk *token.Token) error {
+	return errors.ErrSyntax(fmt.Sprintf("%s was used where %s is expected", actual.YAMLName(), expected.YAMLName()), tk)
+}
+
+type duplicateKeyError struct {
+	err error
+}
+
+func (e *duplicateKeyError) Error() string {
+	return e.err.Error()
+}
+
+func errDuplicateKey(msg string, tk *token.Token) *duplicateKeyError {
+	return &duplicateKeyError{err: errors.ErrSyntax(msg, tk)}
+}
+
+func (d *Decoder) deleteStructKeys(structType reflect.Type, unknownFields map[string]ast.Node) error {
+	if structType.Kind() == reflect.Ptr {
+		structType = structType.Elem()
+	}
+	structFieldMap, err := structFieldMap(structType)
+	if err != nil {
+		return errors.Wrapf(err, "failed to create struct field map")
+	}
+
+	for j := 0; j < structType.NumField(); j++ {
+		field := structType.Field(j)
+		if isIgnoredStructField(field) {
+			continue
+		}
+
+		structField, exists := structFieldMap[field.Name]
+		if !exists {
+			continue
+		}
+
+		if structField.IsInline {
+			d.deleteStructKeys(field.Type, unknownFields)
+		} else {
+			delete(unknownFields, structField.RenderName)
+		}
+	}
+	return nil
+}
+
+func (d *Decoder) lastNode(node ast.Node) ast.Node {
+	switch n := node.(type) {
+	case *ast.MappingNode:
+		if len(n.Values) > 0 {
+			return d.lastNode(n.Values[len(n.Values)-1])
+		}
+	case *ast.MappingValueNode:
+		return d.lastNode(n.Value)
+	case *ast.SequenceNode:
+		if len(n.Values) > 0 {
+			return d.lastNode(n.Values[len(n.Values)-1])
+		}
+	}
+	return node
+}
+
+func (d *Decoder) unmarshalableDocument(node ast.Node) ([]byte, error) {
+	var err error
+	node, err = d.resolveAlias(node)
+	if err != nil {
+		return nil, err
+	}
+	doc := node.String()
+	last := d.lastNode(node)
+	if last != nil && last.Type() == ast.LiteralType {
+		doc += "\n"
+	}
+	return []byte(doc), nil
+}
+
+func (d *Decoder) unmarshalableText(node ast.Node) ([]byte, bool, error) {
+	var err error
+	node, err = d.resolveAlias(node)
+	if err != nil {
+		return nil, false, err
+	}
+	if node.Type() == ast.AnchorType {
+		node = node.(*ast.AnchorNode).Value
+	}
+	switch n := node.(type) {
+	case *ast.StringNode:
+		return []byte(n.Value), true, nil
+	case *ast.LiteralNode:
+		return []byte(n.Value.GetToken().Value), true, nil
+	default:
+		scalar, ok := n.(ast.ScalarNode)
+		if ok {
+			return []byte(fmt.Sprint(scalar.GetValue())), true, nil
+		}
+	}
+	return nil, false, nil
+}
+
+type jsonUnmarshaler interface {
+	UnmarshalJSON([]byte) error
+}
+
+func (d *Decoder) canDecodeByUnmarshaler(dst reflect.Value) bool {
+	iface := dst.Addr().Interface()
+	switch iface.(type) {
+	case BytesUnmarshalerContext:
+		return true
+	case BytesUnmarshaler:
+		return true
+	case InterfaceUnmarshalerContext:
+		return true
+	case InterfaceUnmarshaler:
+		return true
+	case *time.Time:
+		return true
+	case *time.Duration:
+		return true
+	case encoding.TextUnmarshaler:
+		return true
+	case jsonUnmarshaler:
+		return d.useJSONUnmarshaler
+	}
+	return false
+}
+
+func (d *Decoder) decodeByUnmarshaler(ctx context.Context, dst reflect.Value, src ast.Node) error {
+	iface := dst.Addr().Interface()
+
+	if unmarshaler, ok := iface.(BytesUnmarshalerContext); ok {
+		b, err := d.unmarshalableDocument(src)
+		if err != nil {
+			return errors.Wrapf(err, "failed to UnmarshalYAML")
+		}
+		if err := unmarshaler.UnmarshalYAML(ctx, b); err != nil {
+			return errors.Wrapf(err, "failed to UnmarshalYAML")
+		}
+		return nil
+	}
+
+	if unmarshaler, ok := iface.(BytesUnmarshaler); ok {
+		b, err := d.unmarshalableDocument(src)
+		if err != nil {
+			return errors.Wrapf(err, "failed to UnmarshalYAML")
+		}
+		if err := unmarshaler.UnmarshalYAML(b); err != nil {
+			return errors.Wrapf(err, "failed to UnmarshalYAML")
+		}
+		return nil
+	}
+
+	if unmarshaler, ok := iface.(InterfaceUnmarshalerContext); ok {
+		if err := unmarshaler.UnmarshalYAML(ctx, func(v interface{}) error {
+			rv := reflect.ValueOf(v)
+			if rv.Type().Kind() != reflect.Ptr {
+				return errors.ErrDecodeRequiredPointerType
+			}
+			if err := d.decodeValue(ctx, rv.Elem(), src); err != nil {
+				return errors.Wrapf(err, "failed to decode value")
+			}
+			return nil
+		}); err != nil {
+			return errors.Wrapf(err, "failed to UnmarshalYAML")
+		}
+		return nil
+	}
+
+	if unmarshaler, ok := iface.(InterfaceUnmarshaler); ok {
+		if err := unmarshaler.UnmarshalYAML(func(v interface{}) error {
+			rv := reflect.ValueOf(v)
+			if rv.Type().Kind() != reflect.Ptr {
+				return errors.ErrDecodeRequiredPointerType
+			}
+			if err := d.decodeValue(ctx, rv.Elem(), src); err != nil {
+				return errors.Wrapf(err, "failed to decode value")
+			}
+			return nil
+		}); err != nil {
+			return errors.Wrapf(err, "failed to UnmarshalYAML")
+		}
+		return nil
+	}
+
+	if _, ok := iface.(*time.Time); ok {
+		return d.decodeTime(ctx, dst, src)
+	}
+
+	if _, ok := iface.(*time.Duration); ok {
+		return d.decodeDuration(ctx, dst, src)
+	}
+
+	if unmarshaler, isText := iface.(encoding.TextUnmarshaler); isText {
+		b, ok, err := d.unmarshalableText(src)
+		if err != nil {
+			return errors.Wrapf(err, "failed to UnmarshalText")
+		}
+		if ok {
+			if err := unmarshaler.UnmarshalText(b); err != nil {
+				return errors.Wrapf(err, "failed to UnmarshalText")
+			}
+			return nil
+		}
+	}
+
+	if d.useJSONUnmarshaler {
+		if unmarshaler, ok := iface.(jsonUnmarshaler); ok {
+			b, err := d.unmarshalableDocument(src)
+			if err != nil {
+				return errors.Wrapf(err, "failed to UnmarshalJSON")
+			}
+			jsonBytes, err := YAMLToJSON(b)
+			if err != nil {
+				return errors.Wrapf(err, "failed to convert yaml to json")
+			}
+			jsonBytes = bytes.TrimRight(jsonBytes, "\n")
+			if err := unmarshaler.UnmarshalJSON(jsonBytes); err != nil {
+				return errors.Wrapf(err, "failed to UnmarshalJSON")
+			}
+			return nil
+		}
+	}
+
+	return xerrors.Errorf("does not implemented Unmarshaler")
+}
+
+var (
+	astNodeType = reflect.TypeOf((*ast.Node)(nil)).Elem()
+)
+
+func (d *Decoder) decodeValue(ctx context.Context, dst reflect.Value, src ast.Node) error {
+	if src.Type() == ast.AnchorType {
+		anchorName := src.(*ast.AnchorNode).Name.GetToken().Value
+		if _, exists := d.anchorValueMap[anchorName]; !exists {
+			d.anchorValueMap[anchorName] = dst
+		}
+	}
+	if d.canDecodeByUnmarshaler(dst) {
+		if err := d.decodeByUnmarshaler(ctx, dst, src); err != nil {
+			return errors.Wrapf(err, "failed to decode by unmarshaler")
+		}
+		return nil
+	}
+	valueType := dst.Type()
+	switch valueType.Kind() {
+	case reflect.Ptr:
+		if dst.IsNil() {
+			return nil
+		}
+		if src.Type() == ast.NullType {
+			// set nil value to pointer
+			dst.Set(reflect.Zero(valueType))
+			return nil
+		}
+		v := d.createDecodableValue(dst.Type())
+		if err := d.decodeValue(ctx, v, src); err != nil {
+			return errors.Wrapf(err, "failed to decode ptr value")
+		}
+		dst.Set(d.castToAssignableValue(v, dst.Type()))
+	case reflect.Interface:
+		if dst.Type() == astNodeType {
+			dst.Set(reflect.ValueOf(src))
+			return nil
+		}
+		v := reflect.ValueOf(d.nodeToValue(src))
+		if v.IsValid() {
+			dst.Set(v)
+		}
+	case reflect.Map:
+		return d.decodeMap(ctx, dst, src)
+	case reflect.Array:
+		return d.decodeArray(ctx, dst, src)
+	case reflect.Slice:
+		if mapSlice, ok := dst.Addr().Interface().(*MapSlice); ok {
+			return d.decodeMapSlice(ctx, mapSlice, src)
+		}
+		return d.decodeSlice(ctx, dst, src)
+	case reflect.Struct:
+		if mapItem, ok := dst.Addr().Interface().(*MapItem); ok {
+			return d.decodeMapItem(ctx, mapItem, src)
+		}
+		return d.decodeStruct(ctx, dst, src)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		v := d.nodeToValue(src)
+		switch vv := v.(type) {
+		case int64:
+			if !dst.OverflowInt(vv) {
+				dst.SetInt(vv)
+				return nil
+			}
+		case uint64:
+			if vv <= math.MaxInt64 && !dst.OverflowInt(int64(vv)) {
+				dst.SetInt(int64(vv))
+				return nil
+			}
+		case float64:
+			if vv <= math.MaxInt64 && !dst.OverflowInt(int64(vv)) {
+				dst.SetInt(int64(vv))
+				return nil
+			}
+		default:
+			return errTypeMismatch(valueType, reflect.TypeOf(v), src.GetToken())
+		}
+		return errOverflow(valueType, fmt.Sprint(v))
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		v := d.nodeToValue(src)
+		switch vv := v.(type) {
+		case int64:
+			if 0 <= vv && !dst.OverflowUint(uint64(vv)) {
+				dst.SetUint(uint64(vv))
+				return nil
+			}
+		case uint64:
+			if !dst.OverflowUint(vv) {
+				dst.SetUint(vv)
+				return nil
+			}
+		case float64:
+			if 0 <= vv && vv <= math.MaxUint64 && !dst.OverflowUint(uint64(vv)) {
+				dst.SetUint(uint64(vv))
+				return nil
+			}
+		default:
+			return errTypeMismatch(valueType, reflect.TypeOf(v), src.GetToken())
+		}
+		return errOverflow(valueType, fmt.Sprint(v))
+	}
+	v := reflect.ValueOf(d.nodeToValue(src))
+	if v.IsValid() {
+		convertedValue, err := d.convertValue(v, dst.Type(), src)
+		if err != nil {
+			return errors.Wrapf(err, "failed to convert value")
+		}
+		dst.Set(convertedValue)
+	}
+	return nil
+}
+
+func (d *Decoder) createDecodableValue(typ reflect.Type) reflect.Value {
+	for {
+		if typ.Kind() == reflect.Ptr {
+			typ = typ.Elem()
+			continue
+		}
+		break
+	}
+	return reflect.New(typ).Elem()
+}
+
+func (d *Decoder) castToAssignableValue(value reflect.Value, target reflect.Type) reflect.Value {
+	if target.Kind() != reflect.Ptr {
+		return value
+	}
+	maxTryCount := 5
+	tryCount := 0
+	for {
+		if tryCount > maxTryCount {
+			return value
+		}
+		if value.Type().AssignableTo(target) {
+			break
+		}
+		value = value.Addr()
+		tryCount++
+	}
+	return value
+}
+
+func (d *Decoder) createDecodedNewValue(
+	ctx context.Context, typ reflect.Type, defaultVal reflect.Value, node ast.Node,
+) (reflect.Value, error) {
+	if node.Type() == ast.AliasType {
+		aliasName := node.(*ast.AliasNode).Value.GetToken().Value
+		newValue := d.anchorValueMap[aliasName]
+		if newValue.IsValid() {
+			return newValue, nil
+		}
+	}
+	if node.Type() == ast.NullType {
+		return reflect.Zero(typ), nil
+	}
+	newValue := d.createDecodableValue(typ)
+	for defaultVal.Kind() == reflect.Ptr {
+		defaultVal = defaultVal.Elem()
+	}
+	if defaultVal.IsValid() && defaultVal.Type().AssignableTo(newValue.Type()) {
+		newValue.Set(defaultVal)
+	}
+	if err := d.decodeValue(ctx, newValue, node); err != nil {
+		return newValue, errors.Wrapf(err, "failed to decode value")
+	}
+	return newValue, nil
+}
+
+func (d *Decoder) keyToNodeMap(node ast.Node, ignoreMergeKey bool, getKeyOrValueNode func(*ast.MapNodeIter) ast.Node) (map[string]ast.Node, error) {
+	mapNode, err := d.getMapNode(node)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to get map node")
+	}
+	keyMap := map[string]struct{}{}
+	keyToNodeMap := map[string]ast.Node{}
+	if mapNode == nil {
+		return keyToNodeMap, nil
+	}
+	mapIter := mapNode.MapRange()
+	for mapIter.Next() {
+		keyNode := mapIter.Key()
+		if keyNode.Type() == ast.MergeKeyType {
+			if ignoreMergeKey {
+				continue
+			}
+			mergeMap, err := d.keyToNodeMap(mapIter.Value(), ignoreMergeKey, getKeyOrValueNode)
+			if err != nil {
+				return nil, errors.Wrapf(err, "failed to get keyToNodeMap by MergeKey node")
+			}
+			for k, v := range mergeMap {
+				if err := d.validateDuplicateKey(keyMap, k, v); err != nil {
+					return nil, errors.Wrapf(err, "invalid struct key")
+				}
+				keyToNodeMap[k] = v
+			}
+		} else {
+			key, ok := d.nodeToValue(keyNode).(string)
+			if !ok {
+				return nil, errors.Wrapf(err, "failed to decode map key")
+			}
+			if err := d.validateDuplicateKey(keyMap, key, keyNode); err != nil {
+				return nil, errors.Wrapf(err, "invalid struct key")
+			}
+			keyToNodeMap[key] = getKeyOrValueNode(mapIter)
+		}
+	}
+	return keyToNodeMap, nil
+}
+
+func (d *Decoder) keyToKeyNodeMap(node ast.Node, ignoreMergeKey bool) (map[string]ast.Node, error) {
+	m, err := d.keyToNodeMap(node, ignoreMergeKey, func(nodeMap *ast.MapNodeIter) ast.Node { return nodeMap.Key() })
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to get keyToNodeMap")
+	}
+	return m, nil
+}
+
+func (d *Decoder) keyToValueNodeMap(node ast.Node, ignoreMergeKey bool) (map[string]ast.Node, error) {
+	m, err := d.keyToNodeMap(node, ignoreMergeKey, func(nodeMap *ast.MapNodeIter) ast.Node { return nodeMap.Value() })
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to get keyToNodeMap")
+	}
+	return m, nil
+}
+
+func (d *Decoder) setDefaultValueIfConflicted(v reflect.Value, fieldMap StructFieldMap) error {
+	typ := v.Type()
+	if typ.Kind() != reflect.Struct {
+		return nil
+	}
+	embeddedStructFieldMap, err := structFieldMap(typ)
+	if err != nil {
+		return errors.Wrapf(err, "failed to get struct field map by embedded type")
+	}
+	for i := 0; i < typ.NumField(); i++ {
+		field := typ.Field(i)
+		if isIgnoredStructField(field) {
+			continue
+		}
+		structField := embeddedStructFieldMap[field.Name]
+		if !fieldMap.isIncludedRenderName(structField.RenderName) {
+			continue
+		}
+		// if declared same key name, set default value
+		fieldValue := v.Field(i)
+		if fieldValue.CanSet() {
+			fieldValue.Set(reflect.Zero(fieldValue.Type()))
+		}
+	}
+	return nil
+}
+
+// This is a subset of the formats allowed by the regular expression
+// defined at http://yaml.org/type/timestamp.html.
+var allowedTimestampFormats = []string{
+	"2006-1-2T15:4:5.999999999Z07:00", // RCF3339Nano with short date fields.
+	"2006-1-2t15:4:5.999999999Z07:00", // RFC3339Nano with short date fields and lower-case "t".
+	"2006-1-2 15:4:5.999999999",       // space separated with no time zone
+	"2006-1-2",                        // date only
+}
+
+func (d *Decoder) castToTime(src ast.Node) (time.Time, error) {
+	if src == nil {
+		return time.Time{}, nil
+	}
+	v := d.nodeToValue(src)
+	if t, ok := v.(time.Time); ok {
+		return t, nil
+	}
+	s, ok := v.(string)
+	if !ok {
+		return time.Time{}, errTypeMismatch(reflect.TypeOf(time.Time{}), reflect.TypeOf(v), src.GetToken())
+	}
+	for _, format := range allowedTimestampFormats {
+		t, err := time.Parse(format, s)
+		if err != nil {
+			// invalid format
+			continue
+		}
+		return t, nil
+	}
+	return time.Time{}, nil
+}
+
+func (d *Decoder) decodeTime(ctx context.Context, dst reflect.Value, src ast.Node) error {
+	t, err := d.castToTime(src)
+	if err != nil {
+		return errors.Wrapf(err, "failed to convert to time")
+	}
+	dst.Set(reflect.ValueOf(t))
+	return nil
+}
+
+func (d *Decoder) castToDuration(src ast.Node) (time.Duration, error) {
+	if src == nil {
+		return 0, nil
+	}
+	v := d.nodeToValue(src)
+	if t, ok := v.(time.Duration); ok {
+		return t, nil
+	}
+	s, ok := v.(string)
+	if !ok {
+		return 0, errTypeMismatch(reflect.TypeOf(time.Duration(0)), reflect.TypeOf(v), src.GetToken())
+	}
+	t, err := time.ParseDuration(s)
+	if err != nil {
+		return 0, errors.Wrapf(err, "failed to parse duration")
+	}
+	return t, nil
+}
+
+func (d *Decoder) decodeDuration(ctx context.Context, dst reflect.Value, src ast.Node) error {
+	t, err := d.castToDuration(src)
+	if err != nil {
+		return errors.Wrapf(err, "failed to convert to duration")
+	}
+	dst.Set(reflect.ValueOf(t))
+	return nil
+}
+
+// getMergeAliasName support single alias only
+func (d *Decoder) getMergeAliasName(src ast.Node) string {
+	mapNode, err := d.getMapNode(src)
+	if err != nil {
+		return ""
+	}
+	if mapNode == nil {
+		return ""
+	}
+	mapIter := mapNode.MapRange()
+	for mapIter.Next() {
+		key := mapIter.Key()
+		value := mapIter.Value()
+		if key.Type() == ast.MergeKeyType && value.Type() == ast.AliasType {
+			return value.(*ast.AliasNode).Value.GetToken().Value
+		}
+	}
+	return ""
+}
+
+func (d *Decoder) decodeStruct(ctx context.Context, dst reflect.Value, src ast.Node) error {
+	if src == nil {
+		return nil
+	}
+	structType := dst.Type()
+	srcValue := reflect.ValueOf(src)
+	srcType := srcValue.Type()
+	if srcType.Kind() == reflect.Ptr {
+		srcType = srcType.Elem()
+		srcValue = srcValue.Elem()
+	}
+	if structType == srcType {
+		// dst value implements ast.Node
+		dst.Set(srcValue)
+		return nil
+	}
+	structFieldMap, err := structFieldMap(structType)
+	if err != nil {
+		return errors.Wrapf(err, "failed to create struct field map")
+	}
+	ignoreMergeKey := structFieldMap.hasMergeProperty()
+	keyToNodeMap, err := d.keyToValueNodeMap(src, ignoreMergeKey)
+	if err != nil {
+		return errors.Wrapf(err, "failed to get keyToValueNodeMap")
+	}
+	var unknownFields map[string]ast.Node
+	if d.disallowUnknownField {
+		unknownFields, err = d.keyToKeyNodeMap(src, ignoreMergeKey)
+		if err != nil {
+			return errors.Wrapf(err, "failed to get keyToKeyNodeMap")
+		}
+	}
+
+	aliasName := d.getMergeAliasName(src)
+	var foundErr error
+
+	for i := 0; i < structType.NumField(); i++ {
+		field := structType.Field(i)
+		if isIgnoredStructField(field) {
+			continue
+		}
+		structField := structFieldMap[field.Name]
+		if structField.IsInline {
+			fieldValue := dst.FieldByName(field.Name)
+			if structField.IsAutoAlias {
+				if aliasName != "" {
+					newFieldValue := d.anchorValueMap[aliasName]
+					if newFieldValue.IsValid() {
+						fieldValue.Set(d.castToAssignableValue(newFieldValue, fieldValue.Type()))
+					}
+				}
+				continue
+			}
+			if !fieldValue.CanSet() {
+				return xerrors.Errorf("cannot set embedded type as unexported field %s.%s", field.PkgPath, field.Name)
+			}
+			if fieldValue.Type().Kind() == reflect.Ptr && src.Type() == ast.NullType {
+				// set nil value to pointer
+				fieldValue.Set(reflect.Zero(fieldValue.Type()))
+				continue
+			}
+			mapNode := ast.Mapping(nil, false)
+			for k, v := range keyToNodeMap {
+				key := &ast.StringNode{BaseNode: &ast.BaseNode{}, Value: k}
+				mapNode.Values = append(mapNode.Values, ast.MappingValue(nil, key, v))
+			}
+			newFieldValue, err := d.createDecodedNewValue(ctx, fieldValue.Type(), fieldValue, mapNode)
+			if d.disallowUnknownField {
+				if err := d.deleteStructKeys(fieldValue.Type(), unknownFields); err != nil {
+					return errors.Wrapf(err, "cannot delete struct keys")
+				}
+			}
+
+			if err != nil {
+				if foundErr != nil {
+					continue
+				}
+				var te *errors.TypeError
+				if xerrors.As(err, &te) {
+					if te.StructFieldName != nil {
+						fieldName := fmt.Sprintf("%s.%s", structType.Name(), *te.StructFieldName)
+						te.StructFieldName = &fieldName
+					} else {
+						fieldName := fmt.Sprintf("%s.%s", structType.Name(), field.Name)
+						te.StructFieldName = &fieldName
+					}
+					foundErr = te
+					continue
+				} else {
+					foundErr = err
+				}
+				continue
+			}
+			d.setDefaultValueIfConflicted(newFieldValue, structFieldMap)
+			fieldValue.Set(d.castToAssignableValue(newFieldValue, fieldValue.Type()))
+			continue
+		}
+		v, exists := keyToNodeMap[structField.RenderName]
+		if !exists {
+			continue
+		}
+		delete(unknownFields, structField.RenderName)
+		fieldValue := dst.FieldByName(field.Name)
+		if fieldValue.Type().Kind() == reflect.Ptr && src.Type() == ast.NullType {
+			// set nil value to pointer
+			fieldValue.Set(reflect.Zero(fieldValue.Type()))
+			continue
+		}
+		newFieldValue, err := d.createDecodedNewValue(ctx, fieldValue.Type(), fieldValue, v)
+		if err != nil {
+			if foundErr != nil {
+				continue
+			}
+			var te *errors.TypeError
+			if xerrors.As(err, &te) {
+				fieldName := fmt.Sprintf("%s.%s", structType.Name(), field.Name)
+				te.StructFieldName = &fieldName
+				foundErr = te
+			} else {
+				foundErr = err
+			}
+			continue
+		}
+		fieldValue.Set(d.castToAssignableValue(newFieldValue, fieldValue.Type()))
+	}
+	if foundErr != nil {
+		return errors.Wrapf(foundErr, "failed to decode value")
+	}
+
+	// Ignore unknown fields when parsing an inline struct (recognized by a nil token).
+	// Unknown fields are expected (they could be fields from the parent struct).
+	if len(unknownFields) != 0 && d.disallowUnknownField && src.GetToken() != nil {
+		for key, node := range unknownFields {
+			return errUnknownField(fmt.Sprintf(`unknown field "%s"`, key), node.GetToken())
+		}
+	}
+
+	if d.validator != nil {
+		if err := d.validator.Struct(dst.Interface()); err != nil {
+			ev := reflect.ValueOf(err)
+			if ev.Type().Kind() == reflect.Slice {
+				for i := 0; i < ev.Len(); i++ {
+					fieldErr, ok := ev.Index(i).Interface().(FieldError)
+					if !ok {
+						continue
+					}
+					fieldName := fieldErr.StructField()
+					structField, exists := structFieldMap[fieldName]
+					if !exists {
+						continue
+					}
+					node, exists := keyToNodeMap[structField.RenderName]
+					if exists {
+						// TODO: to make FieldError message cutomizable
+						return errors.ErrSyntax(fmt.Sprintf("%s", err), node.GetToken())
+					} else if t := src.GetToken(); t != nil && t.Prev != nil && t.Prev.Prev != nil {
+						// A missing required field will not be in the keyToNodeMap
+						// the error needs to be associated with the parent of the source node
+						return errors.ErrSyntax(fmt.Sprintf("%s", err), t.Prev.Prev)
+					}
+				}
+			}
+			return err
+		}
+	}
+	return nil
+}
+
+func (d *Decoder) decodeArray(ctx context.Context, dst reflect.Value, src ast.Node) error {
+	arrayNode, err := d.getArrayNode(src)
+	if err != nil {
+		return errors.Wrapf(err, "failed to get array node")
+	}
+	if arrayNode == nil {
+		return nil
+	}
+	iter := arrayNode.ArrayRange()
+	arrayValue := reflect.New(dst.Type()).Elem()
+	arrayType := dst.Type()
+	elemType := arrayType.Elem()
+	idx := 0
+
+	var foundErr error
+	for iter.Next() {
+		v := iter.Value()
+		if elemType.Kind() == reflect.Ptr && v.Type() == ast.NullType {
+			// set nil value to pointer
+			arrayValue.Index(idx).Set(reflect.Zero(elemType))
+		} else {
+			dstValue, err := d.createDecodedNewValue(ctx, elemType, reflect.Value{}, v)
+			if err != nil {
+				if foundErr == nil {
+					foundErr = err
+				}
+				continue
+			} else {
+				arrayValue.Index(idx).Set(d.castToAssignableValue(dstValue, elemType))
+			}
+		}
+		idx++
+	}
+	dst.Set(arrayValue)
+	if foundErr != nil {
+		return errors.Wrapf(foundErr, "failed to decode value")
+	}
+	return nil
+}
+
+func (d *Decoder) decodeSlice(ctx context.Context, dst reflect.Value, src ast.Node) error {
+	arrayNode, err := d.getArrayNode(src)
+	if err != nil {
+		return errors.Wrapf(err, "failed to get array node")
+	}
+	if arrayNode == nil {
+		return nil
+	}
+	iter := arrayNode.ArrayRange()
+	sliceType := dst.Type()
+	sliceValue := reflect.MakeSlice(sliceType, 0, iter.Len())
+	elemType := sliceType.Elem()
+
+	var foundErr error
+	for iter.Next() {
+		v := iter.Value()
+		if elemType.Kind() == reflect.Ptr && v.Type() == ast.NullType {
+			// set nil value to pointer
+			sliceValue = reflect.Append(sliceValue, reflect.Zero(elemType))
+			continue
+		}
+		dstValue, err := d.createDecodedNewValue(ctx, elemType, reflect.Value{}, v)
+		if err != nil {
+			if foundErr == nil {
+				foundErr = err
+			}
+			continue
+		}
+		sliceValue = reflect.Append(sliceValue, d.castToAssignableValue(dstValue, elemType))
+	}
+	dst.Set(sliceValue)
+	if foundErr != nil {
+		return errors.Wrapf(foundErr, "failed to decode value")
+	}
+	return nil
+}
+
+func (d *Decoder) decodeMapItem(ctx context.Context, dst *MapItem, src ast.Node) error {
+	mapNode, err := d.getMapNode(src)
+	if err != nil {
+		return errors.Wrapf(err, "failed to get map node")
+	}
+	if mapNode == nil {
+		return nil
+	}
+	mapIter := mapNode.MapRange()
+	if !mapIter.Next() {
+		return nil
+	}
+	key := mapIter.Key()
+	value := mapIter.Value()
+	if key.Type() == ast.MergeKeyType {
+		if err := d.decodeMapItem(ctx, dst, value); err != nil {
+			return errors.Wrapf(err, "failed to decode map with merge key")
+		}
+		return nil
+	}
+	*dst = MapItem{
+		Key:   d.nodeToValue(key),
+		Value: d.nodeToValue(value),
+	}
+	return nil
+}
+
+func (d *Decoder) validateDuplicateKey(keyMap map[string]struct{}, key interface{}, keyNode ast.Node) error {
+	k, ok := key.(string)
+	if !ok {
+		return nil
+	}
+	if d.disallowDuplicateKey {
+		if _, exists := keyMap[k]; exists {
+			return errDuplicateKey(fmt.Sprintf(`duplicate key "%s"`, k), keyNode.GetToken())
+		}
+	}
+	keyMap[k] = struct{}{}
+	return nil
+}
+
+func (d *Decoder) decodeMapSlice(ctx context.Context, dst *MapSlice, src ast.Node) error {
+	mapNode, err := d.getMapNode(src)
+	if err != nil {
+		return errors.Wrapf(err, "failed to get map node")
+	}
+	if mapNode == nil {
+		return nil
+	}
+	mapSlice := MapSlice{}
+	mapIter := mapNode.MapRange()
+	keyMap := map[string]struct{}{}
+	for mapIter.Next() {
+		key := mapIter.Key()
+		value := mapIter.Value()
+		if key.Type() == ast.MergeKeyType {
+			var m MapSlice
+			if err := d.decodeMapSlice(ctx, &m, value); err != nil {
+				return errors.Wrapf(err, "failed to decode map with merge key")
+			}
+			for _, v := range m {
+				if err := d.validateDuplicateKey(keyMap, v.Key, value); err != nil {
+					return errors.Wrapf(err, "invalid map key")
+				}
+				mapSlice = append(mapSlice, v)
+			}
+			continue
+		}
+		k := d.nodeToValue(key)
+		if err := d.validateDuplicateKey(keyMap, k, key); err != nil {
+			return errors.Wrapf(err, "invalid map key")
+		}
+		mapSlice = append(mapSlice, MapItem{
+			Key:   k,
+			Value: d.nodeToValue(value),
+		})
+	}
+	*dst = mapSlice
+	return nil
+}
+
+func (d *Decoder) decodeMap(ctx context.Context, dst reflect.Value, src ast.Node) error {
+	mapNode, err := d.getMapNode(src)
+	if err != nil {
+		return errors.Wrapf(err, "failed to get map node")
+	}
+	if mapNode == nil {
+		return nil
+	}
+	mapType := dst.Type()
+	mapValue := reflect.MakeMap(mapType)
+	keyType := mapValue.Type().Key()
+	valueType := mapValue.Type().Elem()
+	mapIter := mapNode.MapRange()
+	keyMap := map[string]struct{}{}
+	var foundErr error
+	for mapIter.Next() {
+		key := mapIter.Key()
+		value := mapIter.Value()
+		if key.Type() == ast.MergeKeyType {
+			if err := d.decodeMap(ctx, dst, value); err != nil {
+				return errors.Wrapf(err, "failed to decode map with merge key")
+			}
+			iter := dst.MapRange()
+			for iter.Next() {
+				if err := d.validateDuplicateKey(keyMap, iter.Key(), value); err != nil {
+					return errors.Wrapf(err, "invalid map key")
+				}
+				mapValue.SetMapIndex(iter.Key(), iter.Value())
+			}
+			continue
+		}
+		k := reflect.ValueOf(d.nodeToValue(key))
+		if k.IsValid() && k.Type().ConvertibleTo(keyType) {
+			k = k.Convert(keyType)
+		}
+		if k.IsValid() {
+			if err := d.validateDuplicateKey(keyMap, k.Interface(), key); err != nil {
+				return errors.Wrapf(err, "invalid map key")
+			}
+		}
+		if valueType.Kind() == reflect.Ptr && value.Type() == ast.NullType {
+			// set nil value to pointer
+			mapValue.SetMapIndex(k, reflect.Zero(valueType))
+			continue
+		}
+		dstValue, err := d.createDecodedNewValue(ctx, valueType, reflect.Value{}, value)
+		if err != nil {
+			if foundErr == nil {
+				foundErr = err
+			}
+		}
+		if !k.IsValid() {
+			// expect nil key
+			mapValue.SetMapIndex(d.createDecodableValue(keyType), d.castToAssignableValue(dstValue, valueType))
+			continue
+		}
+		mapValue.SetMapIndex(k, d.castToAssignableValue(dstValue, valueType))
+	}
+	dst.Set(mapValue)
+	if foundErr != nil {
+		return errors.Wrapf(foundErr, "failed to decode value")
+	}
+	return nil
+}
+
+func (d *Decoder) fileToReader(file string) (io.Reader, error) {
+	reader, err := os.Open(file)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to open file")
+	}
+	return reader, nil
+}
+
+func (d *Decoder) isYAMLFile(file string) bool {
+	ext := filepath.Ext(file)
+	if ext == ".yml" {
+		return true
+	}
+	if ext == ".yaml" {
+		return true
+	}
+	return false
+}
+
+func (d *Decoder) readersUnderDir(dir string) ([]io.Reader, error) {
+	pattern := fmt.Sprintf("%s/*", dir)
+	matches, err := filepath.Glob(pattern)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to get files by %s", pattern)
+	}
+	readers := []io.Reader{}
+	for _, match := range matches {
+		if !d.isYAMLFile(match) {
+			continue
+		}
+		reader, err := d.fileToReader(match)
+		if err != nil {
+			return nil, errors.Wrapf(err, "failed to get reader")
+		}
+		readers = append(readers, reader)
+	}
+	return readers, nil
+}
+
+func (d *Decoder) readersUnderDirRecursive(dir string) ([]io.Reader, error) {
+	readers := []io.Reader{}
+	if err := filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
+		if !d.isYAMLFile(path) {
+			return nil
+		}
+		reader, err := d.fileToReader(path)
+		if err != nil {
+			return errors.Wrapf(err, "failed to get reader")
+		}
+		readers = append(readers, reader)
+		return nil
+	}); err != nil {
+		return nil, errors.Wrapf(err, "interrupt walk in %s", dir)
+	}
+	return readers, nil
+}
+
+func (d *Decoder) resolveReference() error {
+	for _, opt := range d.opts {
+		if err := opt(d); err != nil {
+			return errors.Wrapf(err, "failed to exec option")
+		}
+	}
+	for _, file := range d.referenceFiles {
+		reader, err := d.fileToReader(file)
+		if err != nil {
+			return errors.Wrapf(err, "failed to get reader")
+		}
+		d.referenceReaders = append(d.referenceReaders, reader)
+	}
+	for _, dir := range d.referenceDirs {
+		if !d.isRecursiveDir {
+			readers, err := d.readersUnderDir(dir)
+			if err != nil {
+				return errors.Wrapf(err, "failed to get readers from under the %s", dir)
+			}
+			d.referenceReaders = append(d.referenceReaders, readers...)
+		} else {
+			readers, err := d.readersUnderDirRecursive(dir)
+			if err != nil {
+				return errors.Wrapf(err, "failed to get readers from under the %s", dir)
+			}
+			d.referenceReaders = append(d.referenceReaders, readers...)
+		}
+	}
+	for _, reader := range d.referenceReaders {
+		bytes, err := ioutil.ReadAll(reader)
+		if err != nil {
+			return errors.Wrapf(err, "failed to read buffer")
+		}
+
+		// assign new anchor definition to anchorMap
+		if _, err := d.parse(bytes); err != nil {
+			return errors.Wrapf(err, "failed to decode")
+		}
+	}
+	d.isResolvedReference = true
+	return nil
+}
+
+func (d *Decoder) parse(bytes []byte) (*ast.File, error) {
+	var parseMode parser.Mode
+	if d.toCommentMap != nil {
+		parseMode = parser.ParseComments
+	}
+	f, err := parser.ParseBytes(bytes, parseMode)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to parse yaml")
+	}
+	normalizedFile := &ast.File{}
+	for _, doc := range f.Docs {
+		// try to decode ast.Node to value and map anchor value to anchorMap
+		if v := d.nodeToValue(doc.Body); v != nil {
+			normalizedFile.Docs = append(normalizedFile.Docs, doc)
+		}
+	}
+	return normalizedFile, nil
+}
+
+func (d *Decoder) isInitialized() bool {
+	return d.parsedFile != nil
+}
+
+func (d *Decoder) decodeInit() error {
+	if !d.isResolvedReference {
+		if err := d.resolveReference(); err != nil {
+			return errors.Wrapf(err, "failed to resolve reference")
+		}
+	}
+	var buf bytes.Buffer
+	if _, err := io.Copy(&buf, d.reader); err != nil {
+		return errors.Wrapf(err, "failed to copy from reader")
+	}
+	file, err := d.parse(buf.Bytes())
+	if err != nil {
+		return errors.Wrapf(err, "failed to decode")
+	}
+	d.parsedFile = file
+	return nil
+}
+
+func (d *Decoder) decode(ctx context.Context, v reflect.Value) error {
+	if len(d.parsedFile.Docs) <= d.streamIndex {
+		return io.EOF
+	}
+	body := d.parsedFile.Docs[d.streamIndex].Body
+	if body == nil {
+		return nil
+	}
+	if err := d.decodeValue(ctx, v.Elem(), body); err != nil {
+		return errors.Wrapf(err, "failed to decode value")
+	}
+	d.streamIndex++
+	return nil
+}
+
+// Decode reads the next YAML-encoded value from its input
+// and stores it in the value pointed to by v.
+//
+// See the documentation for Unmarshal for details about the
+// conversion of YAML into a Go value.
+func (d *Decoder) Decode(v interface{}) error {
+	return d.DecodeContext(context.Background(), v)
+}
+
+// DecodeContext reads the next YAML-encoded value from its input
+// and stores it in the value pointed to by v with context.Context.
+func (d *Decoder) DecodeContext(ctx context.Context, v interface{}) error {
+	rv := reflect.ValueOf(v)
+	if rv.Type().Kind() != reflect.Ptr {
+		return errors.ErrDecodeRequiredPointerType
+	}
+	if d.isInitialized() {
+		if err := d.decode(ctx, rv); err != nil {
+			if err == io.EOF {
+				return err
+			}
+			return errors.Wrapf(err, "failed to decode")
+		}
+		return nil
+	}
+	if err := d.decodeInit(); err != nil {
+		return errors.Wrapf(err, "failed to decodeInit")
+	}
+	if err := d.decode(ctx, rv); err != nil {
+		if err == io.EOF {
+			return err
+		}
+		return errors.Wrapf(err, "failed to decode")
+	}
+	return nil
+}
+
+// DecodeFromNode decodes node into the value pointed to by v.
+func (d *Decoder) DecodeFromNode(node ast.Node, v interface{}) error {
+	return d.DecodeFromNodeContext(context.Background(), node, v)
+}
+
+// DecodeFromNodeContext decodes node into the value pointed to by v with context.Context.
+func (d *Decoder) DecodeFromNodeContext(ctx context.Context, node ast.Node, v interface{}) error {
+	rv := reflect.ValueOf(v)
+	if rv.Type().Kind() != reflect.Ptr {
+		return errors.ErrDecodeRequiredPointerType
+	}
+	if !d.isInitialized() {
+		if err := d.decodeInit(); err != nil {
+			return errors.Wrapf(err, "failed to decodInit")
+		}
+	}
+	// resolve references to the anchor on the same file
+	d.nodeToValue(node)
+	if err := d.decodeValue(ctx, rv.Elem(), node); err != nil {
+		return errors.Wrapf(err, "failed to decode value")
+	}
+	return nil
+}