blob: a2211e9c914c545daa8f7a1325521eacae025140 [file] [log] [blame]
// Copyright 2018 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 prototext
import (
"fmt"
"sort"
"strconv"
"unicode/utf8"
"google.golang.org/protobuf/internal/encoding/messageset"
"google.golang.org/protobuf/internal/encoding/text"
"google.golang.org/protobuf/internal/encoding/wire"
"google.golang.org/protobuf/internal/errors"
"google.golang.org/protobuf/internal/fieldnum"
"google.golang.org/protobuf/internal/flags"
"google.golang.org/protobuf/internal/mapsort"
"google.golang.org/protobuf/internal/pragma"
"google.golang.org/protobuf/proto"
pref "google.golang.org/protobuf/reflect/protoreflect"
"google.golang.org/protobuf/reflect/protoregistry"
)
const defaultIndent = " "
// Format formats the message as a multiline string.
// This function is only intended for human consumption and ignores errors.
// Do not depend on the output being stable. It may change over time across
// different versions of the program.
func Format(m proto.Message) string {
return MarshalOptions{Multiline: true}.Format(m)
}
// Marshal writes the given proto.Message in textproto format using default
// options. Do not depend on the output being stable. It may change over time
// across different versions of the program.
func Marshal(m proto.Message) ([]byte, error) {
return MarshalOptions{}.Marshal(m)
}
// MarshalOptions is a configurable text format marshaler.
type MarshalOptions struct {
pragma.NoUnkeyedLiterals
// AllowPartial allows messages that have missing required fields to marshal
// without returning an error. If AllowPartial is false (the default),
// Marshal will return error if there are any missing required fields.
AllowPartial bool
// EmitUnknown specifies whether to emit unknown fields in the output.
// If specified, the unmarshaler may be unable to parse the output.
// The default is to exclude unknown fields.
EmitUnknown bool
// Multiline specifies whether the marshaler should format the output in
// indented-form with every textual element on a new line.
// If Indent is an empty string, then an arbitrary indent is chosen.
Multiline bool
// Indent specifies the set of indentation characters to use in a multiline
// formatted output such that every entry is preceded by Indent and
// terminated by a newline. If non-empty, then Multiline is treated as true.
// Indent can only be composed of space or tab characters.
Indent string
// Resolver is used for looking up types when expanding google.protobuf.Any
// messages. If nil, this defaults to using protoregistry.GlobalTypes.
Resolver interface {
protoregistry.ExtensionTypeResolver
protoregistry.MessageTypeResolver
}
}
// Format formats the message as a string.
// This method is only intended for human consumption and ignores errors.
// Do not depend on the output being stable. It may change over time across
// different versions of the program.
func (o MarshalOptions) Format(m proto.Message) string {
if m == nil || !m.ProtoReflect().IsValid() {
return "<nil>" // invalid syntax, but okay since this is for debugging
}
o.AllowPartial = true
o.EmitUnknown = true
b, _ := o.Marshal(m)
return string(b)
}
// Marshal writes the given proto.Message in textproto format using options in
// MarshalOptions object. Do not depend on the output being stable. It may
// change over time across different versions of the program.
func (o MarshalOptions) Marshal(m proto.Message) ([]byte, error) {
const outputASCII = false
var delims = [2]byte{'{', '}'}
if o.Multiline && o.Indent == "" {
o.Indent = defaultIndent
}
if o.Resolver == nil {
o.Resolver = protoregistry.GlobalTypes
}
internalEnc, err := text.NewEncoder(o.Indent, delims, outputASCII)
if err != nil {
return nil, err
}
enc := encoder{internalEnc, o}
err = enc.marshalMessage(m.ProtoReflect(), false)
if err != nil {
return nil, err
}
out := enc.Bytes()
if len(o.Indent) > 0 && len(out) > 0 {
out = append(out, '\n')
}
if o.AllowPartial {
return out, nil
}
return out, proto.IsInitialized(m)
}
type encoder struct {
*text.Encoder
opts MarshalOptions
}
// marshalMessage marshals the given protoreflect.Message.
func (e encoder) marshalMessage(m pref.Message, inclDelims bool) error {
messageDesc := m.Descriptor()
if !flags.ProtoLegacy && messageset.IsMessageSet(messageDesc) {
return errors.New("no support for proto1 MessageSets")
}
if inclDelims {
e.StartMessage()
defer e.EndMessage()
}
// Handle Any expansion.
if messageDesc.FullName() == "google.protobuf.Any" {
if e.marshalAny(m) {
return nil
}
// If unable to expand, continue on to marshal Any as a regular message.
}
// Marshal known fields.
fieldDescs := messageDesc.Fields()
size := fieldDescs.Len()
for i := 0; i < size; {
fd := fieldDescs.Get(i)
if od := fd.ContainingOneof(); od != nil {
fd = m.WhichOneof(od)
i += od.Fields().Len()
} else {
i++
}
if fd == nil || !m.Has(fd) {
continue
}
name := fd.Name()
// Use type name for group field name.
if fd.Kind() == pref.GroupKind {
name = fd.Message().Name()
}
val := m.Get(fd)
if err := e.marshalField(string(name), val, fd); err != nil {
return err
}
}
// Marshal extensions.
if err := e.marshalExtensions(m); err != nil {
return err
}
// Marshal unknown fields.
if e.opts.EmitUnknown {
e.marshalUnknown(m.GetUnknown())
}
return nil
}
// marshalField marshals the given field with protoreflect.Value.
func (e encoder) marshalField(name string, val pref.Value, fd pref.FieldDescriptor) error {
switch {
case fd.IsList():
return e.marshalList(name, val.List(), fd)
case fd.IsMap():
return e.marshalMap(name, val.Map(), fd)
default:
e.WriteName(name)
return e.marshalSingular(val, fd)
}
}
// marshalSingular marshals the given non-repeated field value. This includes
// all scalar types, enums, messages, and groups.
func (e encoder) marshalSingular(val pref.Value, fd pref.FieldDescriptor) error {
kind := fd.Kind()
switch kind {
case pref.BoolKind:
e.WriteBool(val.Bool())
case pref.StringKind:
s := val.String()
if !utf8.ValidString(s) {
return errors.InvalidUTF8(string(fd.FullName()))
}
e.WriteString(s)
case pref.Int32Kind, pref.Int64Kind,
pref.Sint32Kind, pref.Sint64Kind,
pref.Sfixed32Kind, pref.Sfixed64Kind:
e.WriteInt(val.Int())
case pref.Uint32Kind, pref.Uint64Kind,
pref.Fixed32Kind, pref.Fixed64Kind:
e.WriteUint(val.Uint())
case pref.FloatKind:
// Encoder.WriteFloat handles the special numbers NaN and infinites.
e.WriteFloat(val.Float(), 32)
case pref.DoubleKind:
// Encoder.WriteFloat handles the special numbers NaN and infinites.
e.WriteFloat(val.Float(), 64)
case pref.BytesKind:
e.WriteString(string(val.Bytes()))
case pref.EnumKind:
num := val.Enum()
if desc := fd.Enum().Values().ByNumber(num); desc != nil {
e.WriteLiteral(string(desc.Name()))
} else {
// Use numeric value if there is no enum description.
e.WriteInt(int64(num))
}
case pref.MessageKind, pref.GroupKind:
return e.marshalMessage(val.Message(), true)
default:
panic(fmt.Sprintf("%v has unknown kind: %v", fd.FullName(), kind))
}
return nil
}
// marshalList marshals the given protoreflect.List as multiple name-value fields.
func (e encoder) marshalList(name string, list pref.List, fd pref.FieldDescriptor) error {
size := list.Len()
for i := 0; i < size; i++ {
e.WriteName(name)
if err := e.marshalSingular(list.Get(i), fd); err != nil {
return err
}
}
return nil
}
// marshalMap marshals the given protoreflect.Map as multiple name-value fields.
func (e encoder) marshalMap(name string, mmap pref.Map, fd pref.FieldDescriptor) error {
var err error
mapsort.Range(mmap, fd.MapKey().Kind(), func(key pref.MapKey, val pref.Value) bool {
e.WriteName(name)
e.StartMessage()
defer e.EndMessage()
e.WriteName("key")
err = e.marshalSingular(key.Value(), fd.MapKey())
if err != nil {
return false
}
e.WriteName("value")
err = e.marshalSingular(val, fd.MapValue())
if err != nil {
return false
}
return true
})
return err
}
// marshalExtensions marshals extension fields.
func (e encoder) marshalExtensions(m pref.Message) error {
type entry struct {
key string
value pref.Value
desc pref.FieldDescriptor
}
// Get a sorted list based on field key first.
var entries []entry
m.Range(func(fd pref.FieldDescriptor, v pref.Value) bool {
if !fd.IsExtension() {
return true
}
// For MessageSet extensions, the name used is the parent message.
name := fd.FullName()
if messageset.IsMessageSetExtension(fd) {
name = name.Parent()
}
entries = append(entries, entry{
key: string(name),
value: v,
desc: fd,
})
return true
})
// Sort extensions lexicographically.
sort.Slice(entries, func(i, j int) bool {
return entries[i].key < entries[j].key
})
// Write out sorted list.
for _, entry := range entries {
// Extension field name is the proto field name enclosed in [].
name := "[" + entry.key + "]"
if err := e.marshalField(name, entry.value, entry.desc); err != nil {
return err
}
}
return nil
}
// marshalUnknown parses the given []byte and marshals fields out.
// This function assumes proper encoding in the given []byte.
func (e encoder) marshalUnknown(b []byte) {
const dec = 10
const hex = 16
for len(b) > 0 {
num, wtype, n := wire.ConsumeTag(b)
b = b[n:]
e.WriteName(strconv.FormatInt(int64(num), dec))
switch wtype {
case wire.VarintType:
var v uint64
v, n = wire.ConsumeVarint(b)
e.WriteUint(v)
case wire.Fixed32Type:
var v uint32
v, n = wire.ConsumeFixed32(b)
e.WriteLiteral("0x" + strconv.FormatUint(uint64(v), hex))
case wire.Fixed64Type:
var v uint64
v, n = wire.ConsumeFixed64(b)
e.WriteLiteral("0x" + strconv.FormatUint(v, hex))
case wire.BytesType:
var v []byte
v, n = wire.ConsumeBytes(b)
e.WriteString(string(v))
case wire.StartGroupType:
e.StartMessage()
var v []byte
v, n = wire.ConsumeGroup(num, b)
e.marshalUnknown(v)
e.EndMessage()
default:
panic(fmt.Sprintf("prototext: error parsing unknown field wire type: %v", wtype))
}
b = b[n:]
}
}
// marshalAny marshals the given google.protobuf.Any message in expanded form.
// It returns true if it was able to marshal, else false.
func (e encoder) marshalAny(any pref.Message) bool {
// Construct the embedded message.
fds := any.Descriptor().Fields()
fdType := fds.ByNumber(fieldnum.Any_TypeUrl)
typeURL := any.Get(fdType).String()
mt, err := e.opts.Resolver.FindMessageByURL(typeURL)
if err != nil {
return false
}
m := mt.New().Interface()
// Unmarshal bytes into embedded message.
fdValue := fds.ByNumber(fieldnum.Any_Value)
value := any.Get(fdValue)
err = proto.UnmarshalOptions{
AllowPartial: true,
Resolver: e.opts.Resolver,
}.Unmarshal(value.Bytes(), m)
if err != nil {
return false
}
// Get current encoder position. If marshaling fails, reset encoder output
// back to this position.
pos := e.Snapshot()
// Field name is the proto field name enclosed in [].
e.WriteName("[" + typeURL + "]")
err = e.marshalMessage(m.ProtoReflect(), true)
if err != nil {
e.Reset(pos)
return false
}
return true
}