+++ /dev/null
-// 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"
- "reflect"
- "strings"
- "sync"
-)
-
-// MapSlice encodes and decodes as a YAML map.
-// The order of keys is preserved when encoding and decoding.
-type MapSlice []MapItem
-
-// MapItem is an item in a MapSlice.
-type MapItem struct {
- Key, Value interface{}
-}
-
-// The Unmarshaler interface may be implemented by types to customize their
-// behavior when being unmarshaled from a YAML document. The UnmarshalYAML
-// method receives a function that may be called to unmarshal the original
-// YAML value into a field or variable. It is safe to call the unmarshal
-// function parameter more than once if necessary.
-type Unmarshaler 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)
-}
-
-// UnmarshalStrict is like Unmarshal except that any fields that are found
-// in the data that do not have corresponding struct members will result in
-// an error.
-func UnmarshalStrict(in []byte, out interface{}) (err error) {
- return unmarshal(in, out, true)
-}
-
-func unmarshal(in []byte, out interface{}, strict bool) (err error) {
- defer handleErr(&err)
- d := newDecoder(strict)
- 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 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.
-// 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.
-// Does not apply to zero valued structs.
-//
-// 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 "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.marshal("", reflect.ValueOf(in))
- e.finish()
- out = e.out
- return
-}
-
-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 "))
-}
-
-// --------------------------------------------------------------------------
-// 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
-}
-
-type fieldInfo struct {
- Key string
- Num int
- OmitEmpty bool
- Flow bool
-
- // 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
-
-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
- 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:
- sinfo, err := getStructInfo(field.Type)
- if err != nil {
- return nil, err
- }
- 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...)
- }
- fieldsMap[finfo.Key] = finfo
- fieldsList = append(fieldsList, finfo)
- }
- default:
- //return nil, errors.New("Option ,inline needs a struct value or map field")
- return nil, errors.New("Option ,inline needs a struct value 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)
- }
-
- fieldsList = append(fieldsList, info)
- fieldsMap[info.Key] = info
- }
-
- sinfo = &structInfo{fieldsMap, fieldsList, inlineMap}
-
- fieldMapMutex.Lock()
- structMap[st] = sinfo
- fieldMapMutex.Unlock()
- return sinfo, nil
-}
-
-func isZero(v reflect.Value) bool {
- switch v.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
-}
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