diff options
Diffstat (limited to 'vendor/github.com/go-openapi/swag/json.go')
-rw-r--r-- | vendor/github.com/go-openapi/swag/json.go | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/vendor/github.com/go-openapi/swag/json.go b/vendor/github.com/go-openapi/swag/json.go new file mode 100644 index 000000000..6e9ec20fc --- /dev/null +++ b/vendor/github.com/go-openapi/swag/json.go @@ -0,0 +1,270 @@ +// Copyright 2015 go-swagger maintainers +// +// 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 swag + +import ( + "bytes" + "encoding/json" + "reflect" + "strings" + "sync" + + "github.com/mailru/easyjson/jlexer" + "github.com/mailru/easyjson/jwriter" +) + +// DefaultJSONNameProvider the default cache for types +var DefaultJSONNameProvider = NewNameProvider() + +const comma = byte(',') + +var closers = map[byte]byte{ + '{': '}', + '[': ']', +} + +type ejMarshaler interface { + MarshalEasyJSON(w *jwriter.Writer) +} + +type ejUnmarshaler interface { + UnmarshalEasyJSON(w *jlexer.Lexer) +} + +// WriteJSON writes json data, prefers finding an appropriate interface to short-circuit the marshaller +// so it takes the fastest option available. +func WriteJSON(data interface{}) ([]byte, error) { + if d, ok := data.(ejMarshaler); ok { + jw := new(jwriter.Writer) + d.MarshalEasyJSON(jw) + return jw.BuildBytes() + } + if d, ok := data.(json.Marshaler); ok { + return d.MarshalJSON() + } + return json.Marshal(data) +} + +// ReadJSON reads json data, prefers finding an appropriate interface to short-circuit the unmarshaller +// so it takes the fastes option available +func ReadJSON(data []byte, value interface{}) error { + if d, ok := value.(ejUnmarshaler); ok { + jl := &jlexer.Lexer{Data: data} + d.UnmarshalEasyJSON(jl) + return jl.Error() + } + if d, ok := value.(json.Unmarshaler); ok { + return d.UnmarshalJSON(data) + } + return json.Unmarshal(data, value) +} + +// DynamicJSONToStruct converts an untyped json structure into a struct +func DynamicJSONToStruct(data interface{}, target interface{}) error { + // TODO: convert straight to a json typed map (mergo + iterate?) + b, err := WriteJSON(data) + if err != nil { + return err + } + if err := ReadJSON(b, target); err != nil { + return err + } + return nil +} + +// ConcatJSON concatenates multiple json objects efficiently +func ConcatJSON(blobs ...[]byte) []byte { + if len(blobs) == 0 { + return nil + } + if len(blobs) == 1 { + return blobs[0] + } + + last := len(blobs) - 1 + var opening, closing byte + a := 0 + idx := 0 + buf := bytes.NewBuffer(nil) + + for i, b := range blobs { + if len(b) > 0 && opening == 0 { // is this an array or an object? + opening, closing = b[0], closers[b[0]] + } + + if opening != '{' && opening != '[' { + continue // don't know how to concatenate non container objects + } + + if len(b) < 3 { // yep empty but also the last one, so closing this thing + if i == last && a > 0 { + buf.WriteByte(closing) + } + continue + } + + idx = 0 + if a > 0 { // we need to join with a comma for everything beyond the first non-empty item + buf.WriteByte(comma) + idx = 1 // this is not the first or the last so we want to drop the leading bracket + } + + if i != last { // not the last one, strip brackets + buf.Write(b[idx : len(b)-1]) + } else { // last one, strip only the leading bracket + buf.Write(b[idx:]) + } + a++ + } + // somehow it ended up being empty, so provide a default value + if buf.Len() == 0 { + buf.WriteByte(opening) + buf.WriteByte(closing) + } + return buf.Bytes() +} + +// ToDynamicJSON turns an object into a properly JSON typed structure +func ToDynamicJSON(data interface{}) interface{} { + // TODO: convert straight to a json typed map (mergo + iterate?) + b, _ := json.Marshal(data) + var res interface{} + json.Unmarshal(b, &res) + return res +} + +// FromDynamicJSON turns an object into a properly JSON typed structure +func FromDynamicJSON(data, target interface{}) error { + b, _ := json.Marshal(data) + return json.Unmarshal(b, target) +} + +// NameProvider represents an object capabale of translating from go property names +// to json property names +// This type is thread-safe. +type NameProvider struct { + lock *sync.Mutex + index map[reflect.Type]nameIndex +} + +type nameIndex struct { + jsonNames map[string]string + goNames map[string]string +} + +// NewNameProvider creates a new name provider +func NewNameProvider() *NameProvider { + return &NameProvider{ + lock: &sync.Mutex{}, + index: make(map[reflect.Type]nameIndex), + } +} + +func buildnameIndex(tpe reflect.Type, idx, reverseIdx map[string]string) { + for i := 0; i < tpe.NumField(); i++ { + targetDes := tpe.Field(i) + + if targetDes.PkgPath != "" { // unexported + continue + } + + if targetDes.Anonymous { // walk embedded structures tree down first + buildnameIndex(targetDes.Type, idx, reverseIdx) + continue + } + + if tag := targetDes.Tag.Get("json"); tag != "" { + + parts := strings.Split(tag, ",") + if len(parts) == 0 { + continue + } + + nm := parts[0] + if nm == "-" { + continue + } + if nm == "" { // empty string means we want to use the Go name + nm = targetDes.Name + } + + idx[nm] = targetDes.Name + reverseIdx[targetDes.Name] = nm + } + } +} + +func newNameIndex(tpe reflect.Type) nameIndex { + var idx = make(map[string]string, tpe.NumField()) + var reverseIdx = make(map[string]string, tpe.NumField()) + + buildnameIndex(tpe, idx, reverseIdx) + return nameIndex{jsonNames: idx, goNames: reverseIdx} +} + +// GetJSONNames gets all the json property names for a type +func (n *NameProvider) GetJSONNames(subject interface{}) []string { + tpe := reflect.Indirect(reflect.ValueOf(subject)).Type() + names, ok := n.index[tpe] + if !ok { + names = n.makeNameIndex(tpe) + } + + var res []string + for k := range names.jsonNames { + res = append(res, k) + } + return res +} + +// GetJSONName gets the json name for a go property name +func (n *NameProvider) GetJSONName(subject interface{}, name string) (string, bool) { + tpe := reflect.Indirect(reflect.ValueOf(subject)).Type() + return n.GetJSONNameForType(tpe, name) +} + +// GetJSONNameForType gets the json name for a go property name on a given type +func (n *NameProvider) GetJSONNameForType(tpe reflect.Type, name string) (string, bool) { + names, ok := n.index[tpe] + if !ok { + names = n.makeNameIndex(tpe) + } + nme, ok := names.goNames[name] + return nme, ok +} + +func (n *NameProvider) makeNameIndex(tpe reflect.Type) nameIndex { + n.lock.Lock() + defer n.lock.Unlock() + names := newNameIndex(tpe) + n.index[tpe] = names + return names +} + +// GetGoName gets the go name for a json property name +func (n *NameProvider) GetGoName(subject interface{}, name string) (string, bool) { + tpe := reflect.Indirect(reflect.ValueOf(subject)).Type() + return n.GetGoNameForType(tpe, name) +} + +// GetGoNameForType gets the go name for a given type for a json property name +func (n *NameProvider) GetGoNameForType(tpe reflect.Type, name string) (string, bool) { + names, ok := n.index[tpe] + if !ok { + names = n.makeNameIndex(tpe) + } + nme, ok := names.jsonNames[name] + return nme, ok +} |