diff options
Diffstat (limited to 'vendor/gopkg.in/yaml.v3/yaml.go')
| -rw-r--r-- | vendor/gopkg.in/yaml.v3/yaml.go | 662 |
1 files changed, 662 insertions, 0 deletions
diff --git a/vendor/gopkg.in/yaml.v3/yaml.go b/vendor/gopkg.in/yaml.v3/yaml.go new file mode 100644 index 00000000..b5d35a50 --- /dev/null +++ b/vendor/gopkg.in/yaml.v3/yaml.go @@ -0,0 +1,662 @@ +// +// Copyright (c) 2011-2019 Canonical Ltd +// +// 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 yaml implements YAML support for the Go language. +// +// Source code and other details for the project are available at GitHub: +// +// https://github.com/go-yaml/yaml +// +package yaml + +import ( + "errors" + "fmt" + "io" + "reflect" + "strings" + "sync" + "unicode/utf8" +) + +// The Unmarshaler interface may be implemented by types to customize their +// behavior when being unmarshaled from a YAML document. +type Unmarshaler interface { + UnmarshalYAML(value *Node) error +} + +type obsoleteUnmarshaler interface { + UnmarshalYAML(unmarshal func(interface{}) error) error +} + +// The Marshaler interface may be implemented by types to customize their +// behavior when being marshaled into a YAML document. The returned value +// is marshaled in place of the original value implementing Marshaler. +// +// If an error is returned by MarshalYAML, the marshaling procedure stops +// and returns with the provided error. +type Marshaler interface { + MarshalYAML() (interface{}, error) +} + +// Unmarshal decodes the first document found within the in byte slice +// and assigns decoded values into the out value. +// +// Maps and pointers (to a struct, string, int, etc) are accepted as out +// values. If an internal pointer within a struct is not initialized, +// the yaml package will initialize it if necessary for unmarshalling +// the provided data. The out parameter must not be nil. +// +// The type of the decoded values should be compatible with the respective +// values in out. If one or more values cannot be decoded due to a type +// mismatches, decoding continues partially until the end of the YAML +// content, and a *yaml.TypeError is returned with details for all +// missed values. +// +// Struct fields are only unmarshalled if they are exported (have an +// upper case first letter), and are unmarshalled using the field name +// lowercased as the default key. Custom keys may be defined via the +// "yaml" name in the field tag: the content preceding the first comma +// is used as the key, and the following comma-separated options are +// used to tweak the marshalling process (see Marshal). +// Conflicting names result in a runtime error. +// +// For example: +// +// type T struct { +// F int `yaml:"a,omitempty"` +// B int +// } +// var t T +// yaml.Unmarshal([]byte("a: 1\nb: 2"), &t) +// +// See the documentation of Marshal for the format of tags and a list of +// supported tag options. +// +func Unmarshal(in []byte, out interface{}) (err error) { + return unmarshal(in, out, false) +} + +// A Decorder reads and decodes YAML values from an input stream. +type Decoder struct { + parser *parser + knownFields bool +} + +// NewDecoder returns a new decoder that reads from r. +// +// The decoder introduces its own buffering and may read +// data from r beyond the YAML values requested. +func NewDecoder(r io.Reader) *Decoder { + return &Decoder{ + parser: newParserFromReader(r), + } +} + +// KnownFields ensures that the keys in decoded mappings to +// exist as fields in the struct being decoded into. +func (dec *Decoder) KnownFields(enable bool) { + dec.knownFields = enable +} + +// 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 (dec *Decoder) Decode(v interface{}) (err error) { + d := newDecoder() + d.knownFields = dec.knownFields + defer handleErr(&err) + node := dec.parser.parse() + if node == nil { + return io.EOF + } + out := reflect.ValueOf(v) + if out.Kind() == reflect.Ptr && !out.IsNil() { + out = out.Elem() + } + d.unmarshal(node, out) + if len(d.terrors) > 0 { + return &TypeError{d.terrors} + } + return nil +} + +// Decode decodes the node and stores its data into the value pointed to by v. +// +// See the documentation for Unmarshal for details about the +// conversion of YAML into a Go value. +func (n *Node) Decode(v interface{}) (err error) { + d := newDecoder() + defer handleErr(&err) + out := reflect.ValueOf(v) + if out.Kind() == reflect.Ptr && !out.IsNil() { + out = out.Elem() + } + d.unmarshal(n, out) + if len(d.terrors) > 0 { + return &TypeError{d.terrors} + } + return nil +} + +func unmarshal(in []byte, out interface{}, strict bool) (err error) { + defer handleErr(&err) + d := newDecoder() + p := newParser(in) + defer p.destroy() + node := p.parse() + if node != nil { + v := reflect.ValueOf(out) + if v.Kind() == reflect.Ptr && !v.IsNil() { + v = v.Elem() + } + d.unmarshal(node, v) + } + if len(d.terrors) > 0 { + return &TypeError{d.terrors} + } + return nil +} + +// Marshal serializes the value provided into a YAML document. The structure +// of the generated document will reflect the structure of the value itself. +// Maps and pointers (to struct, string, int, etc) are accepted as the in value. +// +// Struct fields are only marshalled if they are exported (have an upper case +// first letter), and are marshalled using the field name lowercased as the +// default key. Custom keys may be defined via the "yaml" name in the field +// tag: the content preceding the first comma is used as the key, and the +// following comma-separated options are used to tweak the marshalling process. +// Conflicting names result in a runtime error. +// +// The field tag format accepted is: +// +// `(...) yaml:"[<key>][,<flag1>[,<flag2>]]" (...)` +// +// The following flags are currently supported: +// +// omitempty Only include the field if it's not set to the zero +// value for the type or to empty slices or maps. +// Zero valued structs will be omitted if all their public +// fields are zero, unless they implement an IsZero +// method (see the IsZeroer interface type), in which +// case the field will be included if that method returns true. +// +// flow Marshal using a flow style (useful for structs, +// sequences and maps). +// +// inline Inline the field, which must be a struct or a map, +// causing all of its fields or keys to be processed as if +// they were part of the outer struct. For maps, keys must +// not conflict with the yaml keys of other struct fields. +// +// In addition, if the key is "-", the field is ignored. +// +// For example: +// +// type T struct { +// F int `yaml:"a,omitempty"` +// B int +// } +// yaml.Marshal(&T{B: 2}) // Returns "b: 2\n" +// yaml.Marshal(&T{F: 1}} // Returns "a: 1\nb: 0\n" +// +func Marshal(in interface{}) (out []byte, err error) { + defer handleErr(&err) + e := newEncoder() + defer e.destroy() + e.marshalDoc("", reflect.ValueOf(in)) + e.finish() + out = e.out + return +} + +// An Encoder writes YAML values to an output stream. +type Encoder struct { + encoder *encoder +} + +// NewEncoder returns a new encoder that writes to w. +// The Encoder should be closed after use to flush all data +// to w. +func NewEncoder(w io.Writer) *Encoder { + return &Encoder{ + encoder: newEncoderWithWriter(w), + } +} + +// Encode writes the YAML encoding of v to the stream. +// If multiple items are encoded to the stream, the +// second and subsequent document will be preceded +// with a "---" document separator, but the first will not. +// +// See the documentation for Marshal for details about the conversion of Go +// values to YAML. +func (e *Encoder) Encode(v interface{}) (err error) { + defer handleErr(&err) + e.encoder.marshalDoc("", reflect.ValueOf(v)) + return nil +} + +// SetIndent changes the used indentation used when encoding. +func (e *Encoder) SetIndent(spaces int) { + if spaces < 0 { + panic("yaml: cannot indent to a negative number of spaces") + } + e.encoder.indent = spaces +} + +// Close closes the encoder by writing any remaining data. +// It does not write a stream terminating string "...". +func (e *Encoder) Close() (err error) { + defer handleErr(&err) + e.encoder.finish() + return nil +} + +func handleErr(err *error) { + if v := recover(); v != nil { + if e, ok := v.(yamlError); ok { + *err = e.err + } else { + panic(v) + } + } +} + +type yamlError struct { + err error +} + +func fail(err error) { + panic(yamlError{err}) +} + +func failf(format string, args ...interface{}) { + panic(yamlError{fmt.Errorf("yaml: "+format, args...)}) +} + +// A TypeError is returned by Unmarshal when one or more fields in +// the YAML document cannot be properly decoded into the requested +// types. When this error is returned, the value is still +// unmarshaled partially. +type TypeError struct { + Errors []string +} + +func (e *TypeError) Error() string { + return fmt.Sprintf("yaml: unmarshal errors:\n %s", strings.Join(e.Errors, "\n ")) +} + +type Kind uint32 + +const ( + DocumentNode Kind = 1 << iota + SequenceNode + MappingNode + ScalarNode + AliasNode +) + +type Style uint32 + +const ( + TaggedStyle Style = 1 << iota + DoubleQuotedStyle + SingleQuotedStyle + LiteralStyle + FoldedStyle + FlowStyle +) + +// Node represents an element in the YAML document hierarchy. While documents +// are typically encoded and decoded into higher level types, such as structs +// and maps, Node is an intermediate representation that allows detailed +// control over the content being decoded or encoded. +// +// Values that make use of the Node type interact with the yaml package in the +// same way any other type would do, by encoding and decoding yaml data +// directly or indirectly into them. +// +// For example: +// +// var person struct { +// Name string +// Address yaml.Node +// } +// err := yaml.Unmarshal(data, &person) +// +// Or by itself: +// +// var person Node +// err := yaml.Unmarshal(data, &person) +// +type Node struct { + // Kind defines whether the node is a document, a mapping, a sequence, + // a scalar value, or an alias to another node. The specific data type of + // scalar nodes may be obtained via the ShortTag and LongTag methods. + Kind Kind + + // Style allows customizing the apperance of the node in the tree. + Style Style + + // Tag holds the YAML tag defining the data type for the value. + // When decoding, this field will always be set to the resolved tag, + // even when it wasn't explicitly provided in the YAML content. + // When encoding, if this field is unset the value type will be + // implied from the node properties, and if it is set, it will only + // be serialized into the representation if TaggedStyle is used or + // the implicit tag diverges from the provided one. + Tag string + + // Value holds the unescaped and unquoted represenation of the value. + Value string + + // Anchor holds the anchor name for this node, which allows aliases to point to it. + Anchor string + + // Alias holds the node that this alias points to. Only valid when Kind is AliasNode. + Alias *Node + + // Content holds contained nodes for documents, mappings, and sequences. + Content []*Node + + // HeadComment holds any comments in the lines preceding the node and + // not separated by an empty line. + HeadComment string + + // LineComment holds any comments at the end of the line where the node is in. + LineComment string + + // FootComment holds any comments following the node and before empty lines. + FootComment string + + // Line and Column hold the node position in the decoded YAML text. + // These fields are not respected when encoding the node. + Line int + Column int +} + +// LongTag returns the long form of the tag that indicates the data type for +// the node. If the Tag field isn't explicitly defined, one will be computed +// based on the node properties. +func (n *Node) LongTag() string { + return longTag(n.ShortTag()) +} + +// ShortTag returns the short form of the YAML tag that indicates data type for +// the node. If the Tag field isn't explicitly defined, one will be computed +// based on the node properties. +func (n *Node) ShortTag() string { + if n.indicatedString() { + return strTag + } + if n.Tag == "" || n.Tag == "!" { + switch n.Kind { + case MappingNode: + return mapTag + case SequenceNode: + return seqTag + case AliasNode: + if n.Alias != nil { + return n.Alias.ShortTag() + } + case ScalarNode: + tag, _ := resolve("", n.Value) + return tag + } + return "" + } + return shortTag(n.Tag) +} + +func (n *Node) indicatedString() bool { + return n.Kind == ScalarNode && + (shortTag(n.Tag) == strTag || + (n.Tag == "" || n.Tag == "!") && n.Style&(SingleQuotedStyle|DoubleQuotedStyle|LiteralStyle|FoldedStyle) != 0) +} + +// SetString is a convenience function that sets the node to a string value +// and defines its style in a pleasant way depending on its content. +func (n *Node) SetString(s string) { + n.Kind = ScalarNode + if utf8.ValidString(s) { + n.Value = s + n.Tag = strTag + } else { + n.Value = encodeBase64(s) + n.Tag = binaryTag + } + if strings.Contains(n.Value, "\n") { + n.Style = LiteralStyle + } +} + +// -------------------------------------------------------------------------- +// Maintain a mapping of keys to structure field indexes + +// The code in this section was copied from mgo/bson. + +// structInfo holds details for the serialization of fields of +// a given struct. +type structInfo struct { + FieldsMap map[string]fieldInfo + FieldsList []fieldInfo + + // InlineMap is the number of the field in the struct that + // contains an ,inline map, or -1 if there's none. + InlineMap int + + // InlineUnmarshalers holds indexes to inlined fields that + // contain unmarshaler values. + InlineUnmarshalers [][]int +} + +type fieldInfo struct { + Key string + Num int + OmitEmpty bool + Flow bool + // Id holds the unique field identifier, so we can cheaply + // check for field duplicates without maintaining an extra map. + Id int + + // Inline holds the field index if the field is part of an inlined struct. + Inline []int +} + +var structMap = make(map[reflect.Type]*structInfo) +var fieldMapMutex sync.RWMutex +var unmarshalerType reflect.Type + +func init() { + var v Unmarshaler + unmarshalerType = reflect.ValueOf(&v).Elem().Type() +} + +func getStructInfo(st reflect.Type) (*structInfo, error) { + fieldMapMutex.RLock() + sinfo, found := structMap[st] + fieldMapMutex.RUnlock() + if found { + return sinfo, nil + } + + n := st.NumField() + fieldsMap := make(map[string]fieldInfo) + fieldsList := make([]fieldInfo, 0, n) + inlineMap := -1 + inlineUnmarshalers := [][]int(nil) + for i := 0; i != n; i++ { + field := st.Field(i) + if field.PkgPath != "" && !field.Anonymous { + continue // Private field + } + + info := fieldInfo{Num: i} + + tag := field.Tag.Get("yaml") + if tag == "" && strings.Index(string(field.Tag), ":") < 0 { + tag = string(field.Tag) + } + if tag == "-" { + continue + } + + inline := false + fields := strings.Split(tag, ",") + if len(fields) > 1 { + for _, flag := range fields[1:] { + switch flag { + case "omitempty": + info.OmitEmpty = true + case "flow": + info.Flow = true + case "inline": + inline = true + default: + return nil, errors.New(fmt.Sprintf("unsupported flag %q in tag %q of type %s", flag, tag, st)) + } + } + tag = fields[0] + } + + if inline { + switch field.Type.Kind() { + case reflect.Map: + if inlineMap >= 0 { + return nil, errors.New("multiple ,inline maps in struct " + st.String()) + } + if field.Type.Key() != reflect.TypeOf("") { + return nil, errors.New("option ,inline needs a map with string keys in struct " + st.String()) + } + inlineMap = info.Num + case reflect.Struct, reflect.Ptr: + ftype := field.Type + for ftype.Kind() == reflect.Ptr { + ftype = ftype.Elem() + } + if ftype.Kind() != reflect.Struct { + return nil, errors.New("option ,inline may only be used on a struct or map field") + } + if reflect.PtrTo(ftype).Implements(unmarshalerType) { + inlineUnmarshalers = append(inlineUnmarshalers, []int{i}) + } else { + sinfo, err := getStructInfo(ftype) + if err != nil { + return nil, err + } + for _, index := range sinfo.InlineUnmarshalers { + inlineUnmarshalers = append(inlineUnmarshalers, append([]int{i}, index...)) + } + for _, finfo := range sinfo.FieldsList { + if _, found := fieldsMap[finfo.Key]; found { + msg := "duplicated key '" + finfo.Key + "' in struct " + st.String() + return nil, errors.New(msg) + } + if finfo.Inline == nil { + finfo.Inline = []int{i, finfo.Num} + } else { + finfo.Inline = append([]int{i}, finfo.Inline...) + } + finfo.Id = len(fieldsList) + fieldsMap[finfo.Key] = finfo + fieldsList = append(fieldsList, finfo) + } + } + default: + return nil, errors.New("option ,inline may only be used on a struct or map field") + } + continue + } + + if tag != "" { + info.Key = tag + } else { + info.Key = strings.ToLower(field.Name) + } + + if _, found = fieldsMap[info.Key]; found { + msg := "duplicated key '" + info.Key + "' in struct " + st.String() + return nil, errors.New(msg) + } + + info.Id = len(fieldsList) + fieldsList = append(fieldsList, info) + fieldsMap[info.Key] = info + } + + sinfo = &structInfo{ + FieldsMap: fieldsMap, + FieldsList: fieldsList, + InlineMap: inlineMap, + InlineUnmarshalers: inlineUnmarshalers, + } + + fieldMapMutex.Lock() + structMap[st] = sinfo + fieldMapMutex.Unlock() + return sinfo, nil +} + +// IsZeroer is used to check whether an object is zero to +// determine whether it should be omitted when marshaling +// with the omitempty flag. One notable implementation +// is time.Time. +type IsZeroer interface { + IsZero() bool +} + +func isZero(v reflect.Value) bool { + kind := v.Kind() + if z, ok := v.Interface().(IsZeroer); ok { + if (kind == reflect.Ptr || kind == reflect.Interface) && v.IsNil() { + return true + } + return z.IsZero() + } + switch kind { + case reflect.String: + return len(v.String()) == 0 + case reflect.Interface, reflect.Ptr: + return v.IsNil() + case reflect.Slice: + return v.Len() == 0 + case reflect.Map: + return v.Len() == 0 + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + return v.Int() == 0 + case reflect.Float32, reflect.Float64: + return v.Float() == 0 + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + return v.Uint() == 0 + case reflect.Bool: + return !v.Bool() + case reflect.Struct: + vt := v.Type() + for i := v.NumField() - 1; i >= 0; i-- { + if vt.Field(i).PkgPath != "" { + continue // Private field + } + if !isZero(v.Field(i)) { + return false + } + } + return true + } + return false +} |