diff options
Diffstat (limited to 'vendor/github.com/golang/protobuf/jsonpb/jsonpb.go')
| -rw-r--r-- | vendor/github.com/golang/protobuf/jsonpb/jsonpb.go | 843 |
1 files changed, 843 insertions, 0 deletions
diff --git a/vendor/github.com/golang/protobuf/jsonpb/jsonpb.go b/vendor/github.com/golang/protobuf/jsonpb/jsonpb.go new file mode 100644 index 000000000..82c61624e --- /dev/null +++ b/vendor/github.com/golang/protobuf/jsonpb/jsonpb.go @@ -0,0 +1,843 @@ +// Go support for Protocol Buffers - Google's data interchange format +// +// Copyright 2015 The Go Authors. All rights reserved. +// https://github.com/golang/protobuf +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +/* +Package jsonpb provides marshaling and unmarshaling between protocol buffers and JSON. +It follows the specification at https://developers.google.com/protocol-buffers/docs/proto3#json. + +This package produces a different output than the standard "encoding/json" package, +which does not operate correctly on protocol buffers. +*/ +package jsonpb + +import ( + "bytes" + "encoding/json" + "errors" + "fmt" + "io" + "reflect" + "sort" + "strconv" + "strings" + "time" + + "github.com/golang/protobuf/proto" +) + +// Marshaler is a configurable object for converting between +// protocol buffer objects and a JSON representation for them. +type Marshaler struct { + // Whether to render enum values as integers, as opposed to string values. + EnumsAsInts bool + + // Whether to render fields with zero values. + EmitDefaults bool + + // A string to indent each level by. The presence of this field will + // also cause a space to appear between the field separator and + // value, and for newlines to be appear between fields and array + // elements. + Indent string + + // Whether to use the original (.proto) name for fields. + OrigName bool +} + +// Marshal marshals a protocol buffer into JSON. +func (m *Marshaler) Marshal(out io.Writer, pb proto.Message) error { + writer := &errWriter{writer: out} + return m.marshalObject(writer, pb, "", "") +} + +// MarshalToString converts a protocol buffer object to JSON string. +func (m *Marshaler) MarshalToString(pb proto.Message) (string, error) { + var buf bytes.Buffer + if err := m.Marshal(&buf, pb); err != nil { + return "", err + } + return buf.String(), nil +} + +type int32Slice []int32 + +// For sorting extensions ids to ensure stable output. +func (s int32Slice) Len() int { return len(s) } +func (s int32Slice) Less(i, j int) bool { return s[i] < s[j] } +func (s int32Slice) Swap(i, j int) { s[i], s[j] = s[j], s[i] } + +type wkt interface { + XXX_WellKnownType() string +} + +// marshalObject writes a struct to the Writer. +func (m *Marshaler) marshalObject(out *errWriter, v proto.Message, indent, typeURL string) error { + s := reflect.ValueOf(v).Elem() + + // Handle well-known types. + if wkt, ok := v.(wkt); ok { + switch wkt.XXX_WellKnownType() { + case "DoubleValue", "FloatValue", "Int64Value", "UInt64Value", + "Int32Value", "UInt32Value", "BoolValue", "StringValue", "BytesValue": + // "Wrappers use the same representation in JSON + // as the wrapped primitive type, ..." + sprop := proto.GetProperties(s.Type()) + return m.marshalValue(out, sprop.Prop[0], s.Field(0), indent) + case "Any": + // Any is a bit more involved. + return m.marshalAny(out, v, indent) + case "Duration": + // "Generated output always contains 3, 6, or 9 fractional digits, + // depending on required precision." + s, ns := s.Field(0).Int(), s.Field(1).Int() + d := time.Duration(s)*time.Second + time.Duration(ns)*time.Nanosecond + x := fmt.Sprintf("%.9f", d.Seconds()) + x = strings.TrimSuffix(x, "000") + x = strings.TrimSuffix(x, "000") + out.write(`"`) + out.write(x) + out.write(`s"`) + return out.err + case "Struct": + // Let marshalValue handle the `fields` map. + // TODO: pass the correct Properties if needed. + return m.marshalValue(out, &proto.Properties{}, s.Field(0), indent) + case "Timestamp": + // "RFC 3339, where generated output will always be Z-normalized + // and uses 3, 6 or 9 fractional digits." + s, ns := s.Field(0).Int(), s.Field(1).Int() + t := time.Unix(s, ns).UTC() + // time.RFC3339Nano isn't exactly right (we need to get 3/6/9 fractional digits). + x := t.Format("2006-01-02T15:04:05.000000000") + x = strings.TrimSuffix(x, "000") + x = strings.TrimSuffix(x, "000") + out.write(`"`) + out.write(x) + out.write(`Z"`) + return out.err + case "Value": + // Value has a single oneof. + kind := s.Field(0) + if kind.IsNil() { + // "absence of any variant indicates an error" + return errors.New("nil Value") + } + // oneof -> *T -> T -> T.F + x := kind.Elem().Elem().Field(0) + // TODO: pass the correct Properties if needed. + return m.marshalValue(out, &proto.Properties{}, x, indent) + } + } + + out.write("{") + if m.Indent != "" { + out.write("\n") + } + + firstField := true + + if typeURL != "" { + if err := m.marshalTypeURL(out, indent, typeURL); err != nil { + return err + } + firstField = false + } + + for i := 0; i < s.NumField(); i++ { + value := s.Field(i) + valueField := s.Type().Field(i) + if strings.HasPrefix(valueField.Name, "XXX_") { + continue + } + + // IsNil will panic on most value kinds. + switch value.Kind() { + case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice: + if value.IsNil() { + continue + } + } + + if !m.EmitDefaults { + switch value.Kind() { + case reflect.Bool: + if !value.Bool() { + continue + } + case reflect.Int32, reflect.Int64: + if value.Int() == 0 { + continue + } + case reflect.Uint32, reflect.Uint64: + if value.Uint() == 0 { + continue + } + case reflect.Float32, reflect.Float64: + if value.Float() == 0 { + continue + } + case reflect.String: + if value.Len() == 0 { + continue + } + } + } + + // Oneof fields need special handling. + if valueField.Tag.Get("protobuf_oneof") != "" { + // value is an interface containing &T{real_value}. + sv := value.Elem().Elem() // interface -> *T -> T + value = sv.Field(0) + valueField = sv.Type().Field(0) + } + prop := jsonProperties(valueField, m.OrigName) + if !firstField { + m.writeSep(out) + } + if err := m.marshalField(out, prop, value, indent); err != nil { + return err + } + firstField = false + } + + // Handle proto2 extensions. + if ep, ok := v.(proto.Message); ok { + extensions := proto.RegisteredExtensions(v) + // Sort extensions for stable output. + ids := make([]int32, 0, len(extensions)) + for id, desc := range extensions { + if !proto.HasExtension(ep, desc) { + continue + } + ids = append(ids, id) + } + sort.Sort(int32Slice(ids)) + for _, id := range ids { + desc := extensions[id] + if desc == nil { + // unknown extension + continue + } + ext, extErr := proto.GetExtension(ep, desc) + if extErr != nil { + return extErr + } + value := reflect.ValueOf(ext) + var prop proto.Properties + prop.Parse(desc.Tag) + prop.JSONName = fmt.Sprintf("[%s]", desc.Name) + if !firstField { + m.writeSep(out) + } + if err := m.marshalField(out, &prop, value, indent); err != nil { + return err + } + firstField = false + } + + } + + if m.Indent != "" { + out.write("\n") + out.write(indent) + } + out.write("}") + return out.err +} + +func (m *Marshaler) writeSep(out *errWriter) { + if m.Indent != "" { + out.write(",\n") + } else { + out.write(",") + } +} + +func (m *Marshaler) marshalAny(out *errWriter, any proto.Message, indent string) error { + // "If the Any contains a value that has a special JSON mapping, + // it will be converted as follows: {"@type": xxx, "value": yyy}. + // Otherwise, the value will be converted into a JSON object, + // and the "@type" field will be inserted to indicate the actual data type." + v := reflect.ValueOf(any).Elem() + turl := v.Field(0).String() + val := v.Field(1).Bytes() + + // Only the part of type_url after the last slash is relevant. + mname := turl + if slash := strings.LastIndex(mname, "/"); slash >= 0 { + mname = mname[slash+1:] + } + mt := proto.MessageType(mname) + if mt == nil { + return fmt.Errorf("unknown message type %q", mname) + } + msg := reflect.New(mt.Elem()).Interface().(proto.Message) + if err := proto.Unmarshal(val, msg); err != nil { + return err + } + + if _, ok := msg.(wkt); ok { + out.write("{") + if m.Indent != "" { + out.write("\n") + } + if err := m.marshalTypeURL(out, indent, turl); err != nil { + return err + } + m.writeSep(out) + if m.Indent != "" { + out.write(indent) + out.write(m.Indent) + out.write(`"value": `) + } else { + out.write(`"value":`) + } + if err := m.marshalObject(out, msg, indent+m.Indent, ""); err != nil { + return err + } + if m.Indent != "" { + out.write("\n") + out.write(indent) + } + out.write("}") + return out.err + } + + return m.marshalObject(out, msg, indent, turl) +} + +func (m *Marshaler) marshalTypeURL(out *errWriter, indent, typeURL string) error { + if m.Indent != "" { + out.write(indent) + out.write(m.Indent) + } + out.write(`"@type":`) + if m.Indent != "" { + out.write(" ") + } + b, err := json.Marshal(typeURL) + if err != nil { + return err + } + out.write(string(b)) + return out.err +} + +// marshalField writes field description and value to the Writer. +func (m *Marshaler) marshalField(out *errWriter, prop *proto.Properties, v reflect.Value, indent string) error { + if m.Indent != "" { + out.write(indent) + out.write(m.Indent) + } + out.write(`"`) + out.write(prop.JSONName) + out.write(`":`) + if m.Indent != "" { + out.write(" ") + } + if err := m.marshalValue(out, prop, v, indent); err != nil { + return err + } + return nil +} + +// marshalValue writes the value to the Writer. +func (m *Marshaler) marshalValue(out *errWriter, prop *proto.Properties, v reflect.Value, indent string) error { + + var err error + v = reflect.Indirect(v) + + // Handle repeated elements. + if v.Kind() == reflect.Slice && v.Type().Elem().Kind() != reflect.Uint8 { + out.write("[") + comma := "" + for i := 0; i < v.Len(); i++ { + sliceVal := v.Index(i) + out.write(comma) + if m.Indent != "" { + out.write("\n") + out.write(indent) + out.write(m.Indent) + out.write(m.Indent) + } + if err := m.marshalValue(out, prop, sliceVal, indent+m.Indent); err != nil { + return err + } + comma = "," + } + if m.Indent != "" { + out.write("\n") + out.write(indent) + out.write(m.Indent) + } + out.write("]") + return out.err + } + + // Handle well-known types. + // Most are handled up in marshalObject (because 99% are messages). + type wkt interface { + XXX_WellKnownType() string + } + if wkt, ok := v.Interface().(wkt); ok { + switch wkt.XXX_WellKnownType() { + case "NullValue": + out.write("null") + return out.err + } + } + + // Handle enumerations. + if !m.EnumsAsInts && prop.Enum != "" { + // Unknown enum values will are stringified by the proto library as their + // value. Such values should _not_ be quoted or they will be interpreted + // as an enum string instead of their value. + enumStr := v.Interface().(fmt.Stringer).String() + var valStr string + if v.Kind() == reflect.Ptr { + valStr = strconv.Itoa(int(v.Elem().Int())) + } else { + valStr = strconv.Itoa(int(v.Int())) + } + isKnownEnum := enumStr != valStr + if isKnownEnum { + out.write(`"`) + } + out.write(enumStr) + if isKnownEnum { + out.write(`"`) + } + return out.err + } + + // Handle nested messages. + if v.Kind() == reflect.Struct { + return m.marshalObject(out, v.Addr().Interface().(proto.Message), indent+m.Indent, "") + } + + // Handle maps. + // Since Go randomizes map iteration, we sort keys for stable output. + if v.Kind() == reflect.Map { + out.write(`{`) + keys := v.MapKeys() + sort.Sort(mapKeys(keys)) + for i, k := range keys { + if i > 0 { + out.write(`,`) + } + if m.Indent != "" { + out.write("\n") + out.write(indent) + out.write(m.Indent) + out.write(m.Indent) + } + + b, err := json.Marshal(k.Interface()) + if err != nil { + return err + } + s := string(b) + + // If the JSON is not a string value, encode it again to make it one. + if !strings.HasPrefix(s, `"`) { + b, err := json.Marshal(s) + if err != nil { + return err + } + s = string(b) + } + + out.write(s) + out.write(`:`) + if m.Indent != "" { + out.write(` `) + } + + if err := m.marshalValue(out, prop, v.MapIndex(k), indent+m.Indent); err != nil { + return err + } + } + if m.Indent != "" { + out.write("\n") + out.write(indent) + out.write(m.Indent) + } + out.write(`}`) + return out.err + } + + // Default handling defers to the encoding/json library. + b, err := json.Marshal(v.Interface()) + if err != nil { + return err + } + needToQuote := string(b[0]) != `"` && (v.Kind() == reflect.Int64 || v.Kind() == reflect.Uint64) + if needToQuote { + out.write(`"`) + } + out.write(string(b)) + if needToQuote { + out.write(`"`) + } + return out.err +} + +// Unmarshaler is a configurable object for converting from a JSON +// representation to a protocol buffer object. +type Unmarshaler struct { + // Whether to allow messages to contain unknown fields, as opposed to + // failing to unmarshal. + AllowUnknownFields bool +} + +// UnmarshalNext unmarshals the next protocol buffer from a JSON object stream. +// This function is lenient and will decode any options permutations of the +// related Marshaler. +func (u *Unmarshaler) UnmarshalNext(dec *json.Decoder, pb proto.Message) error { + inputValue := json.RawMessage{} + if err := dec.Decode(&inputValue); err != nil { + return err + } + return u.unmarshalValue(reflect.ValueOf(pb).Elem(), inputValue, nil) +} + +// Unmarshal unmarshals a JSON object stream into a protocol +// buffer. This function is lenient and will decode any options +// permutations of the related Marshaler. +func (u *Unmarshaler) Unmarshal(r io.Reader, pb proto.Message) error { + dec := json.NewDecoder(r) + return u.UnmarshalNext(dec, pb) +} + +// UnmarshalNext unmarshals the next protocol buffer from a JSON object stream. +// This function is lenient and will decode any options permutations of the +// related Marshaler. +func UnmarshalNext(dec *json.Decoder, pb proto.Message) error { + return new(Unmarshaler).UnmarshalNext(dec, pb) +} + +// Unmarshal unmarshals a JSON object stream into a protocol +// buffer. This function is lenient and will decode any options +// permutations of the related Marshaler. +func Unmarshal(r io.Reader, pb proto.Message) error { + return new(Unmarshaler).Unmarshal(r, pb) +} + +// UnmarshalString will populate the fields of a protocol buffer based +// on a JSON string. This function is lenient and will decode any options +// permutations of the related Marshaler. +func UnmarshalString(str string, pb proto.Message) error { + return new(Unmarshaler).Unmarshal(strings.NewReader(str), pb) +} + +// unmarshalValue converts/copies a value into the target. +// prop may be nil. +func (u *Unmarshaler) unmarshalValue(target reflect.Value, inputValue json.RawMessage, prop *proto.Properties) error { + targetType := target.Type() + + // Allocate memory for pointer fields. + if targetType.Kind() == reflect.Ptr { + target.Set(reflect.New(targetType.Elem())) + return u.unmarshalValue(target.Elem(), inputValue, prop) + } + + // Handle well-known types. + type wkt interface { + XXX_WellKnownType() string + } + if wkt, ok := target.Addr().Interface().(wkt); ok { + switch wkt.XXX_WellKnownType() { + case "DoubleValue", "FloatValue", "Int64Value", "UInt64Value", + "Int32Value", "UInt32Value", "BoolValue", "StringValue", "BytesValue": + // "Wrappers use the same representation in JSON + // as the wrapped primitive type, except that null is allowed." + // encoding/json will turn JSON `null` into Go `nil`, + // so we don't have to do any extra work. + return u.unmarshalValue(target.Field(0), inputValue, prop) + case "Any": + return fmt.Errorf("unmarshaling Any not supported yet") + case "Duration": + ivStr := string(inputValue) + if ivStr == "null" { + target.Field(0).SetInt(0) + target.Field(1).SetInt(0) + return nil + } + + unq, err := strconv.Unquote(ivStr) + if err != nil { + return err + } + d, err := time.ParseDuration(unq) + if err != nil { + return fmt.Errorf("bad Duration: %v", err) + } + ns := d.Nanoseconds() + s := ns / 1e9 + ns %= 1e9 + target.Field(0).SetInt(s) + target.Field(1).SetInt(ns) + return nil + case "Timestamp": + ivStr := string(inputValue) + if ivStr == "null" { + target.Field(0).SetInt(0) + target.Field(1).SetInt(0) + return nil + } + + unq, err := strconv.Unquote(ivStr) + if err != nil { + return err + } + t, err := time.Parse(time.RFC3339Nano, unq) + if err != nil { + return fmt.Errorf("bad Timestamp: %v", err) + } + target.Field(0).SetInt(int64(t.Unix())) + target.Field(1).SetInt(int64(t.Nanosecond())) + return nil + } + } + + // Handle enums, which have an underlying type of int32, + // and may appear as strings. + // The case of an enum appearing as a number is handled + // at the bottom of this function. + if inputValue[0] == '"' && prop != nil && prop.Enum != "" { + vmap := proto.EnumValueMap(prop.Enum) + // Don't need to do unquoting; valid enum names + // are from a limited character set. + s := inputValue[1 : len(inputValue)-1] + n, ok := vmap[string(s)] + if !ok { + return fmt.Errorf("unknown value %q for enum %s", s, prop.Enum) + } + if target.Kind() == reflect.Ptr { // proto2 + target.Set(reflect.New(targetType.Elem())) + target = target.Elem() + } + target.SetInt(int64(n)) + return nil + } + + // Handle nested messages. + if targetType.Kind() == reflect.Struct { + var jsonFields map[string]json.RawMessage + if err := json.Unmarshal(inputValue, &jsonFields); err != nil { + return err + } + + consumeField := func(prop *proto.Properties) (json.RawMessage, bool) { + // Be liberal in what names we accept; both orig_name and camelName are okay. + fieldNames := acceptedJSONFieldNames(prop) + + vOrig, okOrig := jsonFields[fieldNames.orig] + vCamel, okCamel := jsonFields[fieldNames.camel] + if !okOrig && !okCamel { + return nil, false + } + // If, for some reason, both are present in the data, favour the camelName. + var raw json.RawMessage + if okOrig { + raw = vOrig + delete(jsonFields, fieldNames.orig) + } + if okCamel { + raw = vCamel + delete(jsonFields, fieldNames.camel) + } + return raw, true + } + + sprops := proto.GetProperties(targetType) + for i := 0; i < target.NumField(); i++ { + ft := target.Type().Field(i) + if strings.HasPrefix(ft.Name, "XXX_") { + continue + } + + valueForField, ok := consumeField(sprops.Prop[i]) + if !ok { + continue + } + + if err := u.unmarshalValue(target.Field(i), valueForField, sprops.Prop[i]); err != nil { + return err + } + } + // Check for any oneof fields. + if len(jsonFields) > 0 { + for _, oop := range sprops.OneofTypes { + raw, ok := consumeField(oop.Prop) + if !ok { + continue + } + nv := reflect.New(oop.Type.Elem()) + target.Field(oop.Field).Set(nv) + if err := u.unmarshalValue(nv.Elem().Field(0), raw, oop.Prop); err != nil { + return err + } + } + } + if !u.AllowUnknownFields && len(jsonFields) > 0 { + // Pick any field to be the scapegoat. + var f string + for fname := range jsonFields { + f = fname + break + } + return fmt.Errorf("unknown field %q in %v", f, targetType) + } + return nil + } + + // Handle arrays (which aren't encoded bytes) + if targetType.Kind() == reflect.Slice && targetType.Elem().Kind() != reflect.Uint8 { + var slc []json.RawMessage + if err := json.Unmarshal(inputValue, &slc); err != nil { + return err + } + len := len(slc) + target.Set(reflect.MakeSlice(targetType, len, len)) + for i := 0; i < len; i++ { + if err := u.unmarshalValue(target.Index(i), slc[i], prop); err != nil { + return err + } + } + return nil + } + + // Handle maps (whose keys are always strings) + if targetType.Kind() == reflect.Map { + var mp map[string]json.RawMessage + if err := json.Unmarshal(inputValue, &mp); err != nil { + return err + } + target.Set(reflect.MakeMap(targetType)) + var keyprop, valprop *proto.Properties + if prop != nil { + // These could still be nil if the protobuf metadata is broken somehow. + // TODO: This won't work because the fields are unexported. + // We should probably just reparse them. + //keyprop, valprop = prop.mkeyprop, prop.mvalprop + } + for ks, raw := range mp { + // Unmarshal map key. The core json library already decoded the key into a + // string, so we handle that specially. Other types were quoted post-serialization. + var k reflect.Value + if targetType.Key().Kind() == reflect.String { + k = reflect.ValueOf(ks) + } else { + k = reflect.New(targetType.Key()).Elem() + if err := u.unmarshalValue(k, json.RawMessage(ks), keyprop); err != nil { + return err + } + } + + // Unmarshal map value. + v := reflect.New(targetType.Elem()).Elem() + if err := u.unmarshalValue(v, raw, valprop); err != nil { + return err + } + target.SetMapIndex(k, v) + } + return nil + } + + // 64-bit integers can be encoded as strings. In this case we drop + // the quotes and proceed as normal. + isNum := targetType.Kind() == reflect.Int64 || targetType.Kind() == reflect.Uint64 + if isNum && strings.HasPrefix(string(inputValue), `"`) { + inputValue = inputValue[1 : len(inputValue)-1] + } + + // Use the encoding/json for parsing other value types. + return json.Unmarshal(inputValue, target.Addr().Interface()) +} + +// jsonProperties returns parsed proto.Properties for the field and corrects JSONName attribute. +func jsonProperties(f reflect.StructField, origName bool) *proto.Properties { + var prop proto.Properties + prop.Init(f.Type, f.Name, f.Tag.Get("protobuf"), &f) + if origName || prop.JSONName == "" { + prop.JSONName = prop.OrigName + } + return &prop +} + +type fieldNames struct { + orig, camel string +} + +func acceptedJSONFieldNames(prop *proto.Properties) fieldNames { + opts := fieldNames{orig: prop.OrigName, camel: prop.OrigName} + if prop.JSONName != "" { + opts.camel = prop.JSONName + } + return opts +} + +// Writer wrapper inspired by https://blog.golang.org/errors-are-values +type errWriter struct { + writer io.Writer + err error +} + +func (w *errWriter) write(str string) { + if w.err != nil { + return + } + _, w.err = w.writer.Write([]byte(str)) +} + +// Map fields may have key types of non-float scalars, strings and enums. +// The easiest way to sort them in some deterministic order is to use fmt. +// If this turns out to be inefficient we can always consider other options, +// such as doing a Schwartzian transform. +// +// Numeric keys are sorted in numeric order per +// https://developers.google.com/protocol-buffers/docs/proto#maps. +type mapKeys []reflect.Value + +func (s mapKeys) Len() int { return len(s) } +func (s mapKeys) Swap(i, j int) { s[i], s[j] = s[j], s[i] } +func (s mapKeys) Less(i, j int) bool { + if k := s[i].Kind(); k == s[j].Kind() { + switch k { + case reflect.Int32, reflect.Int64: + return s[i].Int() < s[j].Int() + case reflect.Uint32, reflect.Uint64: + return s[i].Uint() < s[j].Uint() + } + } + return fmt.Sprint(s[i].Interface()) < fmt.Sprint(s[j].Interface()) +} |