blob: 72924a9050cfbf4441b5ef499a69ed6088307425 [file] [log] [blame]
// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package protojson
import (
"bytes"
"fmt"
"math"
"strconv"
"strings"
"time"
"google.golang.org/protobuf/internal/encoding/json"
"google.golang.org/protobuf/internal/errors"
"google.golang.org/protobuf/internal/genid"
"google.golang.org/protobuf/internal/strs"
"google.golang.org/protobuf/proto"
pref "google.golang.org/protobuf/reflect/protoreflect"
)
type marshalFunc func(encoder, pref.Message) error
// wellKnownTypeMarshaler returns a marshal function if the message type
// has specialized serialization behavior. It returns nil otherwise.
func wellKnownTypeMarshaler(name pref.FullName) marshalFunc {
if name.Parent() == genid.GoogleProtobuf_package {
switch name.Name() {
case genid.Any_message_name:
return encoder.marshalAny
case genid.Timestamp_message_name:
return encoder.marshalTimestamp
case genid.Duration_message_name:
return encoder.marshalDuration
case genid.BoolValue_message_name,
genid.Int32Value_message_name,
genid.Int64Value_message_name,
genid.UInt32Value_message_name,
genid.UInt64Value_message_name,
genid.FloatValue_message_name,
genid.DoubleValue_message_name,
genid.StringValue_message_name,
genid.BytesValue_message_name:
return encoder.marshalWrapperType
case genid.Struct_message_name:
return encoder.marshalStruct
case genid.ListValue_message_name:
return encoder.marshalListValue
case genid.Value_message_name:
return encoder.marshalKnownValue
case genid.FieldMask_message_name:
return encoder.marshalFieldMask
case genid.Empty_message_name:
return encoder.marshalEmpty
}
}
return nil
}
type unmarshalFunc func(decoder, pref.Message) error
// wellKnownTypeUnmarshaler returns a unmarshal function if the message type
// has specialized serialization behavior. It returns nil otherwise.
func wellKnownTypeUnmarshaler(name pref.FullName) unmarshalFunc {
if name.Parent() == genid.GoogleProtobuf_package {
switch name.Name() {
case genid.Any_message_name:
return decoder.unmarshalAny
case genid.Timestamp_message_name:
return decoder.unmarshalTimestamp
case genid.Duration_message_name:
return decoder.unmarshalDuration
case genid.BoolValue_message_name,
genid.Int32Value_message_name,
genid.Int64Value_message_name,
genid.UInt32Value_message_name,
genid.UInt64Value_message_name,
genid.FloatValue_message_name,
genid.DoubleValue_message_name,
genid.StringValue_message_name,
genid.BytesValue_message_name:
return decoder.unmarshalWrapperType
case genid.Struct_message_name:
return decoder.unmarshalStruct
case genid.ListValue_message_name:
return decoder.unmarshalListValue
case genid.Value_message_name:
return decoder.unmarshalKnownValue
case genid.FieldMask_message_name:
return decoder.unmarshalFieldMask
case genid.Empty_message_name:
return decoder.unmarshalEmpty
}
}
return nil
}
// The JSON representation of an Any message uses the regular representation of
// the deserialized, embedded message, with an additional field `@type` which
// contains the type URL. If the embedded message type is well-known and has a
// custom JSON representation, that representation will be embedded adding a
// field `value` which holds the custom JSON in addition to the `@type` field.
func (e encoder) marshalAny(m pref.Message) error {
fds := m.Descriptor().Fields()
fdType := fds.ByNumber(genid.Any_TypeUrl_field_number)
fdValue := fds.ByNumber(genid.Any_Value_field_number)
if !m.Has(fdType) {
if !m.Has(fdValue) {
// If message is empty, marshal out empty JSON object.
e.StartObject()
e.EndObject()
return nil
} else {
// Return error if type_url field is not set, but value is set.
return errors.New("%s: %v is not set", genid.Any_message_fullname, genid.Any_TypeUrl_field_name)
}
}
typeVal := m.Get(fdType)
valueVal := m.Get(fdValue)
// Resolve the type in order to unmarshal value field.
typeURL := typeVal.String()
emt, err := e.opts.Resolver.FindMessageByURL(typeURL)
if err != nil {
return errors.New("%s: unable to resolve %q: %v", genid.Any_message_fullname, typeURL, err)
}
em := emt.New()
err = proto.UnmarshalOptions{
AllowPartial: true, // never check required fields inside an Any
Resolver: e.opts.Resolver,
}.Unmarshal(valueVal.Bytes(), em.Interface())
if err != nil {
return errors.New("%s: unable to unmarshal %q: %v", genid.Any_message_fullname, typeURL, err)
}
// If type of value has custom JSON encoding, marshal out a field "value"
// with corresponding custom JSON encoding of the embedded message as a
// field.
if marshal := wellKnownTypeMarshaler(emt.Descriptor().FullName()); marshal != nil {
e.StartObject()
defer e.EndObject()
// Marshal out @type field.
e.WriteName("@type")
if err := e.WriteString(typeURL); err != nil {
return err
}
e.WriteName("value")
return marshal(e, em)
}
// Else, marshal out the embedded message's fields in this Any object.
if err := e.marshalMessage(em, typeURL); err != nil {
return err
}
return nil
}
func (d decoder) unmarshalAny(m pref.Message) error {
// Peek to check for json.ObjectOpen to avoid advancing a read.
start, err := d.Peek()
if err != nil {
return err
}
if start.Kind() != json.ObjectOpen {
return d.unexpectedTokenError(start)
}
// Use another decoder to parse the unread bytes for @type field. This
// avoids advancing a read from current decoder because the current JSON
// object may contain the fields of the embedded type.
dec := decoder{d.Clone(), UnmarshalOptions{}}
tok, err := findTypeURL(dec)
switch err {
case errEmptyObject:
// An empty JSON object translates to an empty Any message.
d.Read() // Read json.ObjectOpen.
d.Read() // Read json.ObjectClose.
return nil
case errMissingType:
if d.opts.DiscardUnknown {
// Treat all fields as unknowns, similar to an empty object.
return d.skipJSONValue()
}
// Use start.Pos() for line position.
return d.newError(start.Pos(), err.Error())
default:
if err != nil {
return err
}
}
typeURL := tok.ParsedString()
emt, err := d.opts.Resolver.FindMessageByURL(typeURL)
if err != nil {
return d.newError(tok.Pos(), "unable to resolve %v: %q", tok.RawString(), err)
}
// Create new message for the embedded message type and unmarshal into it.
em := emt.New()
if unmarshal := wellKnownTypeUnmarshaler(emt.Descriptor().FullName()); unmarshal != nil {
// If embedded message is a custom type,
// unmarshal the JSON "value" field into it.
if err := d.unmarshalAnyValue(unmarshal, em); err != nil {
return err
}
} else {
// Else unmarshal the current JSON object into it.
if err := d.unmarshalMessage(em, true); err != nil {
return err
}
}
// Serialize the embedded message and assign the resulting bytes to the
// proto value field.
b, err := proto.MarshalOptions{
AllowPartial: true, // No need to check required fields inside an Any.
Deterministic: true,
}.Marshal(em.Interface())
if err != nil {
return d.newError(start.Pos(), "error in marshaling Any.value field: %v", err)
}
fds := m.Descriptor().Fields()
fdType := fds.ByNumber(genid.Any_TypeUrl_field_number)
fdValue := fds.ByNumber(genid.Any_Value_field_number)
m.Set(fdType, pref.ValueOfString(typeURL))
m.Set(fdValue, pref.ValueOfBytes(b))
return nil
}
var errEmptyObject = fmt.Errorf(`empty object`)
var errMissingType = fmt.Errorf(`missing "@type" field`)
// findTypeURL returns the token for the "@type" field value from the given
// JSON bytes. It is expected that the given bytes start with json.ObjectOpen.
// It returns errEmptyObject if the JSON object is empty or errMissingType if
// @type field does not exist. It returns other error if the @type field is not
// valid or other decoding issues.
func findTypeURL(d decoder) (json.Token, error) {
var typeURL string
var typeTok json.Token
numFields := 0
// Skip start object.
d.Read()
Loop:
for {
tok, err := d.Read()
if err != nil {
return json.Token{}, err
}
switch tok.Kind() {
case json.ObjectClose:
if typeURL == "" {
// Did not find @type field.
if numFields > 0 {
return json.Token{}, errMissingType
}
return json.Token{}, errEmptyObject
}
break Loop
case json.Name:
numFields++
if tok.Name() != "@type" {
// Skip value.
if err := d.skipJSONValue(); err != nil {
return json.Token{}, err
}
continue
}
// Return error if this was previously set already.
if typeURL != "" {
return json.Token{}, d.newError(tok.Pos(), `duplicate "@type" field`)
}
// Read field value.
tok, err := d.Read()
if err != nil {
return json.Token{}, err
}
if tok.Kind() != json.String {
return json.Token{}, d.newError(tok.Pos(), `@type field value is not a string: %v`, tok.RawString())
}
typeURL = tok.ParsedString()
if typeURL == "" {
return json.Token{}, d.newError(tok.Pos(), `@type field contains empty value`)
}
typeTok = tok
}
}
return typeTok, nil
}
// skipJSONValue parses a JSON value (null, boolean, string, number, object and
// array) in order to advance the read to the next JSON value. It relies on
// the decoder returning an error if the types are not in valid sequence.
func (d decoder) skipJSONValue() error {
tok, err := d.Read()
if err != nil {
return err
}
// Only need to continue reading for objects and arrays.
switch tok.Kind() {
case json.ObjectOpen:
for {
tok, err := d.Read()
if err != nil {
return err
}
switch tok.Kind() {
case json.ObjectClose:
return nil
case json.Name:
// Skip object field value.
if err := d.skipJSONValue(); err != nil {
return err
}
}
}
case json.ArrayOpen:
for {
tok, err := d.Peek()
if err != nil {
return err
}
switch tok.Kind() {
case json.ArrayClose:
d.Read()
return nil
default:
// Skip array item.
if err := d.skipJSONValue(); err != nil {
return err
}
}
}
}
return nil
}
// unmarshalAnyValue unmarshals the given custom-type message from the JSON
// object's "value" field.
func (d decoder) unmarshalAnyValue(unmarshal unmarshalFunc, m pref.Message) error {
// Skip ObjectOpen, and start reading the fields.
d.Read()
var found bool // Used for detecting duplicate "value".
for {
tok, err := d.Read()
if err != nil {
return err
}
switch tok.Kind() {
case json.ObjectClose:
if !found {
return d.newError(tok.Pos(), `missing "value" field`)
}
return nil
case json.Name:
switch tok.Name() {
case "@type":
// Skip the value as this was previously parsed already.
d.Read()
case "value":
if found {
return d.newError(tok.Pos(), `duplicate "value" field`)
}
// Unmarshal the field value into the given message.
if err := unmarshal(d, m); err != nil {
return err
}
found = true
default:
if d.opts.DiscardUnknown {
if err := d.skipJSONValue(); err != nil {
return err
}
continue
}
return d.newError(tok.Pos(), "unknown field %v", tok.RawString())
}
}
}
}
// Wrapper types are encoded as JSON primitives like string, number or boolean.
func (e encoder) marshalWrapperType(m pref.Message) error {
fd := m.Descriptor().Fields().ByNumber(genid.WrapperValue_Value_field_number)
val := m.Get(fd)
return e.marshalSingular(val, fd)
}
func (d decoder) unmarshalWrapperType(m pref.Message) error {
fd := m.Descriptor().Fields().ByNumber(genid.WrapperValue_Value_field_number)
val, err := d.unmarshalScalar(fd)
if err != nil {
return err
}
m.Set(fd, val)
return nil
}
// The JSON representation for Empty is an empty JSON object.
func (e encoder) marshalEmpty(pref.Message) error {
e.StartObject()
e.EndObject()
return nil
}
func (d decoder) unmarshalEmpty(pref.Message) error {
tok, err := d.Read()
if err != nil {
return err
}
if tok.Kind() != json.ObjectOpen {
return d.unexpectedTokenError(tok)
}
for {
tok, err := d.Read()
if err != nil {
return err
}
switch tok.Kind() {
case json.ObjectClose:
return nil
case json.Name:
if d.opts.DiscardUnknown {
if err := d.skipJSONValue(); err != nil {
return err
}
continue
}
return d.newError(tok.Pos(), "unknown field %v", tok.RawString())
default:
return d.unexpectedTokenError(tok)
}
}
}
// The JSON representation for Struct is a JSON object that contains the encoded
// Struct.fields map and follows the serialization rules for a map.
func (e encoder) marshalStruct(m pref.Message) error {
fd := m.Descriptor().Fields().ByNumber(genid.Struct_Fields_field_number)
return e.marshalMap(m.Get(fd).Map(), fd)
}
func (d decoder) unmarshalStruct(m pref.Message) error {
fd := m.Descriptor().Fields().ByNumber(genid.Struct_Fields_field_number)
return d.unmarshalMap(m.Mutable(fd).Map(), fd)
}
// The JSON representation for ListValue is JSON array that contains the encoded
// ListValue.values repeated field and follows the serialization rules for a
// repeated field.
func (e encoder) marshalListValue(m pref.Message) error {
fd := m.Descriptor().Fields().ByNumber(genid.ListValue_Values_field_number)
return e.marshalList(m.Get(fd).List(), fd)
}
func (d decoder) unmarshalListValue(m pref.Message) error {
fd := m.Descriptor().Fields().ByNumber(genid.ListValue_Values_field_number)
return d.unmarshalList(m.Mutable(fd).List(), fd)
}
// The JSON representation for a Value is dependent on the oneof field that is
// set. Each of the field in the oneof has its own custom serialization rule. A
// Value message needs to be a oneof field set, else it is an error.
func (e encoder) marshalKnownValue(m pref.Message) error {
od := m.Descriptor().Oneofs().ByName(genid.Value_Kind_oneof_name)
fd := m.WhichOneof(od)
if fd == nil {
return errors.New("%s: none of the oneof fields is set", genid.Value_message_fullname)
}
if fd.Number() == genid.Value_NumberValue_field_number {
if v := m.Get(fd).Float(); math.IsNaN(v) || math.IsInf(v, 0) {
return errors.New("%s: invalid %v value", genid.Value_NumberValue_field_fullname, v)
}
}
return e.marshalSingular(m.Get(fd), fd)
}
func (d decoder) unmarshalKnownValue(m pref.Message) error {
tok, err := d.Peek()
if err != nil {
return err
}
var fd pref.FieldDescriptor
var val pref.Value
switch tok.Kind() {
case json.Null:
d.Read()
fd = m.Descriptor().Fields().ByNumber(genid.Value_NullValue_field_number)
val = pref.ValueOfEnum(0)
case json.Bool:
tok, err := d.Read()
if err != nil {
return err
}
fd = m.Descriptor().Fields().ByNumber(genid.Value_BoolValue_field_number)
val = pref.ValueOfBool(tok.Bool())
case json.Number:
tok, err := d.Read()
if err != nil {
return err
}
fd = m.Descriptor().Fields().ByNumber(genid.Value_NumberValue_field_number)
var ok bool
val, ok = unmarshalFloat(tok, 64)
if !ok {
return d.newError(tok.Pos(), "invalid %v: %v", genid.Value_message_fullname, tok.RawString())
}
case json.String:
// A JSON string may have been encoded from the number_value field,
// e.g. "NaN", "Infinity", etc. Parsing a proto double type also allows
// for it to be in JSON string form. Given this custom encoding spec,
// however, there is no way to identify that and hence a JSON string is
// always assigned to the string_value field, which means that certain
// encoding cannot be parsed back to the same field.
tok, err := d.Read()
if err != nil {
return err
}
fd = m.Descriptor().Fields().ByNumber(genid.Value_StringValue_field_number)
val = pref.ValueOfString(tok.ParsedString())
case json.ObjectOpen:
fd = m.Descriptor().Fields().ByNumber(genid.Value_StructValue_field_number)
val = m.NewField(fd)
if err := d.unmarshalStruct(val.Message()); err != nil {
return err
}
case json.ArrayOpen:
fd = m.Descriptor().Fields().ByNumber(genid.Value_ListValue_field_number)
val = m.NewField(fd)
if err := d.unmarshalListValue(val.Message()); err != nil {
return err
}
default:
return d.newError(tok.Pos(), "invalid %v: %v", genid.Value_message_fullname, tok.RawString())
}
m.Set(fd, val)
return nil
}
// The JSON representation for a Duration is a JSON string that ends in the
// suffix "s" (indicating seconds) and is preceded by the number of seconds,
// with nanoseconds expressed as fractional seconds.
//
// Durations less than one second are represented with a 0 seconds field and a
// positive or negative nanos field. For durations of one second or more, a
// non-zero value for the nanos field must be of the same sign as the seconds
// field.
//
// Duration.seconds must be from -315,576,000,000 to +315,576,000,000 inclusive.
// Duration.nanos must be from -999,999,999 to +999,999,999 inclusive.
const (
secondsInNanos = 999999999
maxSecondsInDuration = 315576000000
)
func (e encoder) marshalDuration(m pref.Message) error {
fds := m.Descriptor().Fields()
fdSeconds := fds.ByNumber(genid.Duration_Seconds_field_number)
fdNanos := fds.ByNumber(genid.Duration_Nanos_field_number)
secsVal := m.Get(fdSeconds)
nanosVal := m.Get(fdNanos)
secs := secsVal.Int()
nanos := nanosVal.Int()
if secs < -maxSecondsInDuration || secs > maxSecondsInDuration {
return errors.New("%s: seconds out of range %v", genid.Duration_message_fullname, secs)
}
if nanos < -secondsInNanos || nanos > secondsInNanos {
return errors.New("%s: nanos out of range %v", genid.Duration_message_fullname, nanos)
}
if (secs > 0 && nanos < 0) || (secs < 0 && nanos > 0) {
return errors.New("%s: signs of seconds and nanos do not match", genid.Duration_message_fullname)
}
// Generated output always contains 0, 3, 6, or 9 fractional digits,
// depending on required precision, followed by the suffix "s".
var sign string
if secs < 0 || nanos < 0 {
sign, secs, nanos = "-", -1*secs, -1*nanos
}
x := fmt.Sprintf("%s%d.%09d", sign, secs, nanos)
x = strings.TrimSuffix(x, "000")
x = strings.TrimSuffix(x, "000")
x = strings.TrimSuffix(x, ".000")
e.WriteString(x + "s")
return nil
}
func (d decoder) unmarshalDuration(m pref.Message) error {
tok, err := d.Read()
if err != nil {
return err
}
if tok.Kind() != json.String {
return d.unexpectedTokenError(tok)
}
secs, nanos, ok := parseDuration(tok.ParsedString())
if !ok {
return d.newError(tok.Pos(), "invalid %v value %v", genid.Duration_message_fullname, tok.RawString())
}
// Validate seconds. No need to validate nanos because parseDuration would
// have covered that already.
if secs < -maxSecondsInDuration || secs > maxSecondsInDuration {
return d.newError(tok.Pos(), "%v value out of range: %v", genid.Duration_message_fullname, tok.RawString())
}
fds := m.Descriptor().Fields()
fdSeconds := fds.ByNumber(genid.Duration_Seconds_field_number)
fdNanos := fds.ByNumber(genid.Duration_Nanos_field_number)
m.Set(fdSeconds, pref.ValueOfInt64(secs))
m.Set(fdNanos, pref.ValueOfInt32(nanos))
return nil
}
// parseDuration parses the given input string for seconds and nanoseconds value
// for the Duration JSON format. The format is a decimal number with a suffix
// 's'. It can have optional plus/minus sign. There needs to be at least an
// integer or fractional part. Fractional part is limited to 9 digits only for
// nanoseconds precision, regardless of whether there are trailing zero digits.
// Example values are 1s, 0.1s, 1.s, .1s, +1s, -1s, -.1s.
func parseDuration(input string) (int64, int32, bool) {
b := []byte(input)
size := len(b)
if size < 2 {
return 0, 0, false
}
if b[size-1] != 's' {
return 0, 0, false
}
b = b[:size-1]
// Read optional plus/minus symbol.
var neg bool
switch b[0] {
case '-':
neg = true
b = b[1:]
case '+':
b = b[1:]
}
if len(b) == 0 {
return 0, 0, false
}
// Read the integer part.
var intp []byte
switch {
case b[0] == '0':
b = b[1:]
case '1' <= b[0] && b[0] <= '9':
intp = b[0:]
b = b[1:]
n := 1
for len(b) > 0 && '0' <= b[0] && b[0] <= '9' {
n++
b = b[1:]
}
intp = intp[:n]
case b[0] == '.':
// Continue below.
default:
return 0, 0, false
}
hasFrac := false
var frac [9]byte
if len(b) > 0 {
if b[0] != '.' {
return 0, 0, false
}
// Read the fractional part.
b = b[1:]
n := 0
for len(b) > 0 && n < 9 && '0' <= b[0] && b[0] <= '9' {
frac[n] = b[0]
n++
b = b[1:]
}
// It is not valid if there are more bytes left.
if len(b) > 0 {
return 0, 0, false
}
// Pad fractional part with 0s.
for i := n; i < 9; i++ {
frac[i] = '0'
}
hasFrac = true
}
var secs int64
if len(intp) > 0 {
var err error
secs, err = strconv.ParseInt(string(intp), 10, 64)
if err != nil {
return 0, 0, false
}
}
var nanos int64
if hasFrac {
nanob := bytes.TrimLeft(frac[:], "0")
if len(nanob) > 0 {
var err error
nanos, err = strconv.ParseInt(string(nanob), 10, 32)
if err != nil {
return 0, 0, false
}
}
}
if neg {
if secs > 0 {
secs = -secs
}
if nanos > 0 {
nanos = -nanos
}
}
return secs, int32(nanos), true
}
// The JSON representation for a Timestamp is a JSON string in the RFC 3339
// format, i.e. "{year}-{month}-{day}T{hour}:{min}:{sec}[.{frac_sec}]Z" where
// {year} is always expressed using four digits while {month}, {day}, {hour},
// {min}, and {sec} are zero-padded to two digits each. The fractional seconds,
// which can go up to 9 digits, up to 1 nanosecond resolution, is optional. The
// "Z" suffix indicates the timezone ("UTC"); the timezone is required. Encoding
// should always use UTC (as indicated by "Z") and a decoder should be able to
// accept both UTC and other timezones (as indicated by an offset).
//
// Timestamp.seconds must be from 0001-01-01T00:00:00Z to 9999-12-31T23:59:59Z
// inclusive.
// Timestamp.nanos must be from 0 to 999,999,999 inclusive.
const (
maxTimestampSeconds = 253402300799
minTimestampSeconds = -62135596800
)
func (e encoder) marshalTimestamp(m pref.Message) error {
fds := m.Descriptor().Fields()
fdSeconds := fds.ByNumber(genid.Timestamp_Seconds_field_number)
fdNanos := fds.ByNumber(genid.Timestamp_Nanos_field_number)
secsVal := m.Get(fdSeconds)
nanosVal := m.Get(fdNanos)
secs := secsVal.Int()
nanos := nanosVal.Int()
if secs < minTimestampSeconds || secs > maxTimestampSeconds {
return errors.New("%s: seconds out of range %v", genid.Timestamp_message_fullname, secs)
}
if nanos < 0 || nanos > secondsInNanos {
return errors.New("%s: nanos out of range %v", genid.Timestamp_message_fullname, nanos)
}
// Uses RFC 3339, where generated output will be Z-normalized and uses 0, 3,
// 6 or 9 fractional digits.
t := time.Unix(secs, nanos).UTC()
x := t.Format("2006-01-02T15:04:05.000000000")
x = strings.TrimSuffix(x, "000")
x = strings.TrimSuffix(x, "000")
x = strings.TrimSuffix(x, ".000")
e.WriteString(x + "Z")
return nil
}
func (d decoder) unmarshalTimestamp(m pref.Message) error {
tok, err := d.Read()
if err != nil {
return err
}
if tok.Kind() != json.String {
return d.unexpectedTokenError(tok)
}
t, err := time.Parse(time.RFC3339Nano, tok.ParsedString())
if err != nil {
return d.newError(tok.Pos(), "invalid %v value %v", genid.Timestamp_message_fullname, tok.RawString())
}
// Validate seconds. No need to validate nanos because time.Parse would have
// covered that already.
secs := t.Unix()
if secs < minTimestampSeconds || secs > maxTimestampSeconds {
return d.newError(tok.Pos(), "%v value out of range: %v", genid.Timestamp_message_fullname, tok.RawString())
}
fds := m.Descriptor().Fields()
fdSeconds := fds.ByNumber(genid.Timestamp_Seconds_field_number)
fdNanos := fds.ByNumber(genid.Timestamp_Nanos_field_number)
m.Set(fdSeconds, pref.ValueOfInt64(secs))
m.Set(fdNanos, pref.ValueOfInt32(int32(t.Nanosecond())))
return nil
}
// The JSON representation for a FieldMask is a JSON string where paths are
// separated by a comma. Fields name in each path are converted to/from
// lower-camel naming conventions. Encoding should fail if the path name would
// end up differently after a round-trip.
func (e encoder) marshalFieldMask(m pref.Message) error {
fd := m.Descriptor().Fields().ByNumber(genid.FieldMask_Paths_field_number)
list := m.Get(fd).List()
paths := make([]string, 0, list.Len())
for i := 0; i < list.Len(); i++ {
s := list.Get(i).String()
if !pref.FullName(s).IsValid() {
return errors.New("%s contains invalid path: %q", genid.FieldMask_Paths_field_fullname, s)
}
// Return error if conversion to camelCase is not reversible.
cc := strs.JSONCamelCase(s)
if s != strs.JSONSnakeCase(cc) {
return errors.New("%s contains irreversible value %q", genid.FieldMask_Paths_field_fullname, s)
}
paths = append(paths, cc)
}
e.WriteString(strings.Join(paths, ","))
return nil
}
func (d decoder) unmarshalFieldMask(m pref.Message) error {
tok, err := d.Read()
if err != nil {
return err
}
if tok.Kind() != json.String {
return d.unexpectedTokenError(tok)
}
str := strings.TrimSpace(tok.ParsedString())
if str == "" {
return nil
}
paths := strings.Split(str, ",")
fd := m.Descriptor().Fields().ByNumber(genid.FieldMask_Paths_field_number)
list := m.Mutable(fd).List()
for _, s0 := range paths {
s := strs.JSONSnakeCase(s0)
if strings.Contains(s0, "_") || !pref.FullName(s).IsValid() {
return d.newError(tok.Pos(), "%v contains invalid path: %q", genid.FieldMask_Paths_field_fullname, s0)
}
list.Append(pref.ValueOfString(s))
}
return nil
}