package text

import "google.golang.org/protobuf/internal/encoding/text"

Package text implements the text format for protocol buffers. This package has no semantic understanding for protocol buffers and is only a parser and composer for the format.

There is no formal specification for the protobuf text format, as such the C++ implementation (see google::protobuf::TextFormat) is the reference implementation of the text format.

This package is neither a superset nor a subset of the C++ implementation. This implementation permits a more liberal grammar in some cases to be backwards compatible with the historical Go implementation. Future parsings unique to Go should not be added. Some grammars allowed by the C++ implementation are deliberately not implemented here because they are considered a bug by the protobuf team and should not be replicated.

The Go implementation should implement a sufficient amount of the C++ grammar such that the default text serialization by C++ can be parsed by Go. However, just because the C++ parser accepts some input does not mean that the Go implementation should as well.

The text format is almost a superset of JSON except:

• message keys are not quoted strings, but identifiers
• the top-level value must be a message without the delimiters

Index ¶

• Variables
• func AppendString(b []byte, s string) []byte
• func TokenEquals(x, y Token) bool
• func UnmarshalString(s string) (string, error)
• type Decoder
• func NewDecoder(b []byte) *Decoder
• func (d *Decoder) Peek() (Token, error)
• func (d *Decoder) Position(idx int) (line int, column int)
• func (d *Decoder) Read() (Token, error)
• type Encoder
• func NewEncoder(buf []byte, indent string, delims [2]byte, outputASCII bool) (*Encoder, error)
• func (e *Encoder) Bytes() []byte
• func (e *Encoder) EndMessage()
• func (e *Encoder) Reset(es encoderState)
• func (e *Encoder) Snapshot() encoderState
• func (e *Encoder) StartMessage()
• func (e *Encoder) WriteBool(b bool)
• func (e *Encoder) WriteFloat(n float64, bitSize int)
• func (e *Encoder) WriteInt(n int64)
• func (e *Encoder) WriteLiteral(s string)
• func (e *Encoder) WriteName(s string)
• func (e *Encoder) WriteString(s string)
• func (e *Encoder) WriteUint(n uint64)
• type Kind
• func (t Kind) String() string
• type NameKind
• func (t NameKind) String() string
• type Token
• func (t Token) Bool() (bool, bool)
• func (t Token) Enum() (string, bool)
• func (t Token) FieldNumber() int32
• func (t Token) Float32() (float32, bool)
• func (t Token) Float64() (float64, bool)
• func (t Token) HasSeparator() bool
• func (t Token) IdentName() string
• func (t Token) Int32() (int32, bool)
• func (t Token) Int64() (int64, bool)
• func (t Token) Kind() Kind
• func (t Token) NameKind() NameKind
• func (t Token) Pos() int
• func (t Token) RawString() string
• func (t Token) String() (string, bool)
• func (t Token) TypeName() string
• func (t Token) Uint32() (uint32, bool)
• func (t Token) Uint64() (uint64, bool)

Variables ¶

var ErrUnexpectedEOF = errors.New("%v", io.ErrUnexpectedEOF)

ErrUnexpectedEOF means that EOF was encountered in the middle of the input.

Functions ¶

func AppendString ¶

func AppendString(b []byte, s string) []byte

AppendString appends the escaped form of the input string to b.

func TokenEquals ¶

func TokenEquals(x, y Token) bool

TokenEquals returns true if given Tokens are equal, else false.

func UnmarshalString ¶

func UnmarshalString(s string) (string, error)

UnmarshalString returns an unescaped string given a textproto string value. String value needs to contain single or double quotes. This is only used by internal/encoding/defval package for unmarshaling bytes.

Types ¶

type Decoder ¶

type Decoder struct {
	// contains filtered or unexported fields
}

Decoder is a token-based textproto decoder.

func NewDecoder ¶

func NewDecoder(b []byte) *Decoder

NewDecoder returns a Decoder to read the given []byte.

func (*Decoder) Peek ¶

func (d *Decoder) Peek() (Token, error)

Peek looks ahead and returns the next token and error without advancing a read.

func (*Decoder) Position ¶

func (d *Decoder) Position(idx int) (line int, column int)

Position returns line and column number of given index of the original input. It will panic if index is out of range.

func (*Decoder) Read ¶

func (d *Decoder) Read() (Token, error)

Read returns the next token. It will return an error if there is no valid token.

type Encoder ¶

type Encoder struct {
	// contains filtered or unexported fields
}

Encoder provides methods to write out textproto constructs and values. The user is responsible for producing valid sequences of constructs and values.

func NewEncoder ¶

func NewEncoder(buf []byte, indent string, delims [2]byte, outputASCII bool) (*Encoder, error)

NewEncoder returns an Encoder.

If indent is a non-empty string, it causes every entry in a List or Message to be preceded by the indent and trailed by a newline.

If delims is not the zero value, it controls the delimiter characters used for messages (e.g., "{}" vs "<>").

If outputASCII is true, strings will be serialized in such a way that multi-byte UTF-8 sequences are escaped. This property ensures that the overall output is ASCII (as opposed to UTF-8).

func (*Encoder) Bytes ¶

func (e *Encoder) Bytes() []byte

Bytes returns the content of the written bytes.

func (*Encoder) EndMessage ¶

func (e *Encoder) EndMessage()

EndMessage writes out the '}' or '>' symbol.

func (*Encoder) Reset ¶

func (e *Encoder) Reset(es encoderState)

Reset resets the Encoder to the given encoderState from a Snapshot.

func (*Encoder) Snapshot ¶

func (e *Encoder) Snapshot() encoderState

Snapshot returns the current snapshot for use in Reset.

func (*Encoder) StartMessage ¶

func (e *Encoder) StartMessage()

StartMessage writes out the '{' or '<' symbol.

func (*Encoder) WriteBool ¶

func (e *Encoder) WriteBool(b bool)

WriteBool writes out the given boolean value.

func (*Encoder) WriteFloat ¶

func (e *Encoder) WriteFloat(n float64, bitSize int)

WriteFloat writes out the given float value for given bitSize.

func (*Encoder) WriteInt ¶

func (e *Encoder) WriteInt(n int64)

WriteInt writes out the given signed integer value.

func (*Encoder) WriteLiteral ¶

func (e *Encoder) WriteLiteral(s string)

WriteLiteral writes out the given string as a literal value without quotes. This is used for writing enum literal strings.

func (*Encoder) WriteName ¶

func (e *Encoder) WriteName(s string)

WriteName writes out the field name and the separator ':'.

func (*Encoder) WriteString ¶

func (e *Encoder) WriteString(s string)

WriteString writes out the given string value.

func (*Encoder) WriteUint ¶

func (e *Encoder) WriteUint(n uint64)

WriteUint writes out the given unsigned integer value.

type Kind ¶

type Kind uint8

Kind represents a token kind expressible in the textproto format.

const (
	Invalid Kind = iota
	EOF
	Name   // Name indicates the field name.
	Scalar // Scalar are scalar values, e.g. "string", 47, ENUM_LITERAL, true.
	MessageOpen
	MessageClose
	ListOpen
	ListClose
)

Kind values.

func (Kind) String ¶

func (t Kind) String() string

type NameKind ¶

type NameKind uint8

NameKind represents different types of field names.

const (
	IdentName NameKind = iota + 1
	TypeName
	FieldNumber
)

NameKind values.

func (NameKind) String ¶

func (t NameKind) String() string

type Token ¶

type Token struct {
	// contains filtered or unexported fields
}

Token provides a parsed token kind and value. Values are provided by the different accessor methods.

func (Token) Bool ¶

func (t Token) Bool() (bool, bool)

Bool returns the bool value for a Scalar type.

func (Token) Enum ¶

func (t Token) Enum() (string, bool)

Enum returns the literal value for a Scalar type for use as enum literals.

func (Token) FieldNumber ¶

func (t Token) FieldNumber() int32

FieldNumber returns the value for FieldNumber type. It returns a non-negative int32 value. Caller will still need to validate for the correct field number range.

func (Token) Float32 ¶

func (t Token) Float32() (float32, bool)

Float32 returns the float32 value for a Scalar type.

func (Token) Float64 ¶

func (t Token) Float64() (float64, bool)

Float64 returns the float64 value for a Scalar type.

func (Token) HasSeparator ¶

func (t Token) HasSeparator() bool

HasSeparator returns true if the field name is followed by the separator char ':', else false. It panics if type is not Name.

func (Token) IdentName ¶

func (t Token) IdentName() string

IdentName returns the value for IdentName type.

func (Token) Int32 ¶

func (t Token) Int32() (int32, bool)

Int32 returns the int32 value for a Scalar type.

func (Token) Int64 ¶

func (t Token) Int64() (int64, bool)

Int64 returns the int64 value for a Scalar type.

func (Token) Kind ¶

func (t Token) Kind() Kind

Kind returns the token kind.

func (Token) NameKind ¶

func (t Token) NameKind() NameKind

NameKind returns IdentName, TypeName or FieldNumber. It panics if type is not Name.

func (Token) Pos ¶

func (t Token) Pos() int

Pos returns the token position from the input.

func (Token) RawString ¶

func (t Token) RawString() string

RawString returns the read value in string.

func (Token) String ¶

func (t Token) String() (string, bool)

String returns the string value for a Scalar type.

func (Token) TypeName ¶

func (t Token) TypeName() string

TypeName returns the value for TypeName type.

func (Token) Uint32 ¶

func (t Token) Uint32() (uint32, bool)

Uint32 returns the uint32 value for a Scalar type.

func (Token) Uint64 ¶

func (t Token) Uint64() (uint64, bool)

Uint64 returns the uint64 value for a Scalar type.

Source Files ¶

decode.go decode_number.go decode_string.go decode_token.go doc.go encode.go