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// 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"
"math"
"reflect"
"sort"
"strconv"
"strings"
"time"
"github.com/golang/protobuf/proto"
stpb "github.com/golang/protobuf/ptypes/struct"
)
const secondInNanos = int64(time.Second / time.Nanosecond)
// 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
// A custom URL resolver to use when marshaling Any messages to JSON.
// If unset, the default resolution strategy is to extract the
// fully-qualified type name from the type URL and pass that to
// proto.MessageType(string).
AnyResolver AnyResolver
}
// AnyResolver takes a type URL, present in an Any message, and resolves it into
// an instance of the associated message.
type AnyResolver interface {
Resolve(typeUrl string) (proto.Message, error)
}
func defaultResolveAny(typeUrl string) (proto.Message, error) {
// Only the part of typeUrl after the last slash is relevant.
mname := typeUrl
if slash := strings.LastIndex(mname, "/"); slash >= 0 {
mname = mname[slash+1:]
}
mt := proto.MessageType(mname)
if mt == nil {
return nil, fmt.Errorf("unknown message type %q", mname)
}
return reflect.New(mt.Elem()).Interface().(proto.Message), nil
}
// JSONPBMarshaler is implemented by protobuf messages that customize the
// way they are marshaled to JSON. Messages that implement this should
// also implement JSONPBUnmarshaler so that the custom format can be
// parsed.
//
// The JSON marshaling must follow the proto to JSON specification:
// https://developers.google.com/protocol-buffers/docs/proto3#json
type JSONPBMarshaler interface {
MarshalJSONPB(*Marshaler) ([]byte, error)
}
// JSONPBUnmarshaler is implemented by protobuf messages that customize
// the way they are unmarshaled from JSON. Messages that implement this
// should also implement JSONPBMarshaler so that the custom format can be
// produced.
//
// The JSON unmarshaling must follow the JSON to proto specification:
// https://developers.google.com/protocol-buffers/docs/proto3#json
type JSONPBUnmarshaler interface {
UnmarshalJSONPB(*Unmarshaler, []byte) error
}
// Marshal marshals a protocol buffer into JSON.
func (m *Marshaler) Marshal(out io.Writer, pb proto.Message) error {
v := reflect.ValueOf(pb)
if pb == nil || (v.Kind() == reflect.Ptr && v.IsNil()) {
return errors.New("Marshal called with nil")
}
// Check for unset required fields first.
if err := checkRequiredFields(pb); err != nil {
return err
}
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
var nonFinite = map[string]float64{
`"NaN"`: math.NaN(),
`"Infinity"`: math.Inf(1),
`"-Infinity"`: math.Inf(-1),
}
// 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 {
if jsm, ok := v.(JSONPBMarshaler); ok {
b, err := jsm.MarshalJSONPB(m)
if err != nil {
return err
}
if typeURL != "" {
// we are marshaling this object to an Any type
var js map[string]*json.RawMessage
if err = json.Unmarshal(b, &js); err != nil {
return fmt.Errorf("type %T produced invalid JSON: %v", v, err)
}
turl, err := json.Marshal(typeURL)
if err != nil {
return fmt.Errorf("failed to marshal type URL %q to JSON: %v", typeURL, err)
}
js["@type"] = (*json.RawMessage)(&turl)
if b, err = json.Marshal(js); err != nil {
return err
}
}
out.write(string(b))
return out.err
}
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 0, 3, 6, or 9 fractional digits,
// depending on required precision."
s, ns := s.Field(0).Int(), s.Field(1).Int()
if ns <= -secondInNanos || ns >= secondInNanos {
return fmt.Errorf("ns out of range (%v, %v)", -secondInNanos, secondInNanos)
}
if (s > 0 && ns < 0) || (s < 0 && ns > 0) {
return errors.New("signs of seconds and nanos do not match")
}
if s < 0 {
ns = -ns
}
x := fmt.Sprintf("%d.%09d", s, ns)
x = strings.TrimSuffix(x, "000")
x = strings.TrimSuffix(x, "000")
x = strings.TrimSuffix(x, ".000")
out.write(`"`)
out.write(x)
out.write(`s"`)
return out.err
case "Struct", "ListValue":
// Let marshalValue handle the `Struct.fields` map or the `ListValue.values` slice.
// 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 0, 3, 6 or 9 fractional digits."
s, ns := s.Field(0).Int(), s.Field(1).Int()
if ns < 0 || ns >= secondInNanos {
return fmt.Errorf("ns out of range [0, %v)", secondInNanos)
}
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")
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:
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
}
case reflect.Map, reflect.Ptr, reflect.Slice:
if value.IsNil() {
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()
var msg proto.Message
var err error
if m.AnyResolver != nil {
msg, err = m.AnyResolver.Resolve(turl)
} else {
msg, err = defaultResolveAny(turl)
}
if err != nil {
return err
}
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 nil pointer
if v.Kind() == reflect.Invalid {
out.write("null")
return out.err
}
// 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).
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)
}
// TODO handle map key prop properly
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(` `)
}
vprop := prop
if prop != nil && prop.MapValProp != nil {
vprop = prop.MapValProp
}
if err := m.marshalValue(out, vprop, 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
}
// Handle non-finite floats, e.g. NaN, Infinity and -Infinity.
if v.Kind() == reflect.Float32 || v.Kind() == reflect.Float64 {
f := v.Float()
var sval string
switch {
case math.IsInf(f, 1):
sval = `"Infinity"`
case math.IsInf(f, -1):
sval = `"-Infinity"`
case math.IsNaN(f):
sval = `"NaN"`
}
if sval != "" {
out.write(sval)
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
// A custom URL resolver to use when unmarshaling Any messages from JSON.
// If unset, the default resolution strategy is to extract the
// fully-qualified type name from the type URL and pass that to
// proto.MessageType(string).
AnyResolver AnyResolver
}
// 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
}
if err := u.unmarshalValue(reflect.ValueOf(pb).Elem(), inputValue, nil); err != nil {
return err
}
return checkRequiredFields(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 (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 {
// If input value is "null" and target is a pointer type, then the field should be treated as not set
// UNLESS the target is structpb.Value, in which case it should be set to structpb.NullValue.
_, isJSONPBUnmarshaler := target.Interface().(JSONPBUnmarshaler)
if string(inputValue) == "null" && targetType != reflect.TypeOf(&stpb.Value{}) && !isJSONPBUnmarshaler {
return nil
}
target.Set(reflect.New(targetType.Elem()))
return u.unmarshalValue(target.Elem(), inputValue, prop)
}
if jsu, ok := target.Addr().Interface().(JSONPBUnmarshaler); ok {
return jsu.UnmarshalJSONPB(u, []byte(inputValue))
}
// Handle well-known types that are not pointers.
if w, ok := target.Addr().Interface().(wkt); ok {
switch w.XXX_WellKnownType() {
case "DoubleValue", "FloatValue", "Int64Value", "UInt64Value",
"Int32Value", "UInt32Value", "BoolValue", "StringValue", "BytesValue":
return u.unmarshalValue(target.Field(0), inputValue, prop)
case "Any":
// Use json.RawMessage pointer type instead of value to support pre-1.8 version.
// 1.8 changed RawMessage.MarshalJSON from pointer type to value type, see
// https://github.com/golang/go/issues/14493
var jsonFields map[string]*json.RawMessage
if err := json.Unmarshal(inputValue, &jsonFields); err != nil {
return err
}
val, ok := jsonFields["@type"]
if !ok || val == nil {
return errors.New("Any JSON doesn't have '@type'")
}
var turl string
if err := json.Unmarshal([]byte(*val), &turl); err != nil {
return fmt.Errorf("can't unmarshal Any's '@type': %q", *val)
}
target.Field(0).SetString(turl)
var m proto.Message
var err error
if u.AnyResolver != nil {
m, err = u.AnyResolver.Resolve(turl)
} else {
m, err = defaultResolveAny(turl)
}
if err != nil {
return err
}
if _, ok := m.(wkt); ok {
val, ok := jsonFields["value"]
if !ok {
return errors.New("Any JSON doesn't have 'value'")
}
if err := u.unmarshalValue(reflect.ValueOf(m).Elem(), *val, nil); err != nil {
return fmt.Errorf("can't unmarshal Any nested proto %T: %v", m, err)
}
} else {
delete(jsonFields, "@type")
nestedProto, err := json.Marshal(jsonFields)
if err != nil {
return fmt.Errorf("can't generate JSON for Any's nested proto to be unmarshaled: %v", err)
}
if err = u.unmarshalValue(reflect.ValueOf(m).Elem(), nestedProto, nil); err != nil {
return fmt.Errorf("can't unmarshal Any nested proto %T: %v", m, err)
}
}
b, err := proto.Marshal(m)
if err != nil {
return fmt.Errorf("can't marshal proto %T into Any.Value: %v", m, err)
}
target.Field(1).SetBytes(b)
return nil
case "Duration":
unq, err := unquote(string(inputValue))
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":
unq, err := unquote(string(inputValue))
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(t.Unix())
target.Field(1).SetInt(int64(t.Nanosecond()))
return nil
case "Struct":
var m map[string]json.RawMessage
if err := json.Unmarshal(inputValue, &m); err != nil {
return fmt.Errorf("bad StructValue: %v", err)
}
target.Field(0).Set(reflect.ValueOf(map[string]*stpb.Value{}))
for k, jv := range m {
pv := &stpb.Value{}
if err := u.unmarshalValue(reflect.ValueOf(pv).Elem(), jv, prop); err != nil {
return fmt.Errorf("bad value in StructValue for key %q: %v", k, err)
}
target.Field(0).SetMapIndex(reflect.ValueOf(k), reflect.ValueOf(pv))
}
return nil
case "ListValue":
var s []json.RawMessage
if err := json.Unmarshal(inputValue, &s); err != nil {
return fmt.Errorf("bad ListValue: %v", err)
}
target.Field(0).Set(reflect.ValueOf(make([]*stpb.Value, len(s))))
for i, sv := range s {
if err := u.unmarshalValue(target.Field(0).Index(i), sv, prop); err != nil {
return err
}
}
return nil
case "Value":
ivStr := string(inputValue)
if ivStr == "null" {
target.Field(0).Set(reflect.ValueOf(&stpb.Value_NullValue{}))
} else if v, err := strconv.ParseFloat(ivStr, 0); err == nil {
target.Field(0).Set(reflect.ValueOf(&stpb.Value_NumberValue{v}))
} else if v, err := unquote(ivStr); err == nil {
target.Field(0).Set(reflect.ValueOf(&stpb.Value_StringValue{v}))
} else if v, err := strconv.ParseBool(ivStr); err == nil {
target.Field(0).Set(reflect.ValueOf(&stpb.Value_BoolValue{v}))
} else if err := json.Unmarshal(inputValue, &[]json.RawMessage{}); err == nil {
lv := &stpb.ListValue{}
target.Field(0).Set(reflect.ValueOf(&stpb.Value_ListValue{lv}))
return u.unmarshalValue(reflect.ValueOf(lv).Elem(), inputValue, prop)
} else if err := json.Unmarshal(inputValue, &map[string]json.RawMessage{}); err == nil {
sv := &stpb.Struct{}
target.Field(0).Set(reflect.ValueOf(&stpb.Value_StructValue{sv}))
return u.unmarshalValue(reflect.ValueOf(sv).Elem(), inputValue, prop)
} else {
return fmt.Errorf("unrecognized type for Value %q", ivStr)
}
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()
}
if targetType.Kind() != reflect.Int32 {
return fmt.Errorf("invalid target %q for enum %s", targetType.Kind(), prop.Enum)
}
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
}
}
}
// Handle proto2 extensions.
if len(jsonFields) > 0 {
if ep, ok := target.Addr().Interface().(proto.Message); ok {
for _, ext := range proto.RegisteredExtensions(ep) {
name := fmt.Sprintf("[%s]", ext.Name)
raw, ok := jsonFields[name]
if !ok {
continue
}
delete(jsonFields, name)
nv := reflect.New(reflect.TypeOf(ext.ExtensionType).Elem())
if err := u.unmarshalValue(nv.Elem(), raw, nil); err != nil {
return err
}
if err := proto.SetExtension(ep, ext, nv.Interface()); 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
}
if slc != nil {
l := len(slc)
target.Set(reflect.MakeSlice(targetType, l, l))
for i := 0; i < l; 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
}
if mp != nil {
target.Set(reflect.MakeMap(targetType))
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()
var kprop *proto.Properties
if prop != nil && prop.MapKeyProp != nil {
kprop = prop.MapKeyProp
}
if err := u.unmarshalValue(k, json.RawMessage(ks), kprop); err != nil {
return err
}
}
// Unmarshal map value.
v := reflect.New(targetType.Elem()).Elem()
var vprop *proto.Properties
if prop != nil && prop.MapValProp != nil {
vprop = prop.MapValProp
}
if err := u.unmarshalValue(v, raw, vprop); err != nil {
return err
}
target.SetMapIndex(k, v)
}
}
return nil
}
// Non-finite numbers can be encoded as strings.
isFloat := targetType.Kind() == reflect.Float32 || targetType.Kind() == reflect.Float64
if isFloat {
if num, ok := nonFinite[string(inputValue)]; ok {
target.SetFloat(num)
return nil
}
}
// integers & floats 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 ||
targetType.Kind() == reflect.Int32 || targetType.Kind() == reflect.Uint32 ||
targetType.Kind() == reflect.Float32 || targetType.Kind() == reflect.Float64
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())
}
func unquote(s string) (string, error) {
var ret string
err := json.Unmarshal([]byte(s), &ret)
return ret, err
}
// 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.String:
return s[i].String() < s[j].String()
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())
}
// checkRequiredFields returns an error if any required field in the given proto message is not set.
// This function is used by both Marshal and Unmarshal. While required fields only exist in a
// proto2 message, a proto3 message can contain proto2 message(s).
func checkRequiredFields(pb proto.Message) error {
// Most well-known type messages do not contain required fields. The "Any" type may contain
// a message that has required fields.
//
// When an Any message is being marshaled, the code will invoked proto.Unmarshal on Any.Value
// field in order to transform that into JSON, and that should have returned an error if a
// required field is not set in the embedded message.
//
// When an Any message is being unmarshaled, the code will have invoked proto.Marshal on the
// embedded message to store the serialized message in Any.Value field, and that should have
// returned an error if a required field is not set.
if _, ok := pb.(wkt); ok {
return nil
}
v := reflect.ValueOf(pb)
// Skip message if it is not a struct pointer.
if v.Kind() != reflect.Ptr {
return nil
}
v = v.Elem()
if v.Kind() != reflect.Struct {
return nil
}
for i := 0; i < v.NumField(); i++ {
field := v.Field(i)
sfield := v.Type().Field(i)
if sfield.PkgPath != "" {
// blank PkgPath means the field is exported; skip if not exported
continue
}
if strings.HasPrefix(sfield.Name, "XXX_") {
continue
}
// Oneof field is an interface implemented by wrapper structs containing the actual oneof
// field, i.e. an interface containing &T{real_value}.
if sfield.Tag.Get("protobuf_oneof") != "" {
if field.Kind() != reflect.Interface {
continue
}
v := field.Elem()
if v.Kind() != reflect.Ptr || v.IsNil() {
continue
}
v = v.Elem()
if v.Kind() != reflect.Struct || v.NumField() < 1 {
continue
}
field = v.Field(0)
sfield = v.Type().Field(0)
}
protoTag := sfield.Tag.Get("protobuf")
if protoTag == "" {
continue
}
var prop proto.Properties
prop.Init(sfield.Type, sfield.Name, protoTag, &sfield)
switch field.Kind() {
case reflect.Map:
if field.IsNil() {
continue
}
// Check each map value.
keys := field.MapKeys()
for _, k := range keys {
v := field.MapIndex(k)
if err := checkRequiredFieldsInValue(v); err != nil {
return err
}
}
case reflect.Slice:
// Handle non-repeated type, e.g. bytes.
if !prop.Repeated {
if prop.Required && field.IsNil() {
return fmt.Errorf("required field %q is not set", prop.Name)
}
continue
}
// Handle repeated type.
if field.IsNil() {
continue
}
// Check each slice item.
for i := 0; i < field.Len(); i++ {
v := field.Index(i)
if err := checkRequiredFieldsInValue(v); err != nil {
return err
}
}
case reflect.Ptr:
if field.IsNil() {
if prop.Required {
return fmt.Errorf("required field %q is not set", prop.Name)
}
continue
}
if err := checkRequiredFieldsInValue(field); err != nil {
return err
}
}
}
// Handle proto2 extensions.
for _, ext := range proto.RegisteredExtensions(pb) {
if !proto.HasExtension(pb, ext) {
continue
}
ep, err := proto.GetExtension(pb, ext)
if err != nil {
return err
}
err = checkRequiredFieldsInValue(reflect.ValueOf(ep))
if err != nil {
return err
}
}
return nil
}
func checkRequiredFieldsInValue(v reflect.Value) error {
if pm, ok := v.Interface().(proto.Message); ok {
return checkRequiredFields(pm)
}
return nil
}