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gitea/vendor/go.mongodb.org/mongo-driver/bson/bsonrw/extjson_writer.go

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Go

// Copyright (C) MongoDB, Inc. 2017-present.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may
// not use this file except in compliance with the License. You may obtain
// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
package bsonrw
import (
"bytes"
"encoding/base64"
"fmt"
"go.mongodb.org/mongo-driver/bson/primitive"
"io"
"math"
"sort"
"strconv"
"strings"
"sync"
"time"
"unicode/utf8"
)
var ejvwPool = sync.Pool{
New: func() interface{} {
return new(extJSONValueWriter)
},
}
// ExtJSONValueWriterPool is a pool for ExtJSON ValueWriters.
type ExtJSONValueWriterPool struct {
pool sync.Pool
}
// NewExtJSONValueWriterPool creates a new pool for ValueWriter instances that write to ExtJSON.
func NewExtJSONValueWriterPool() *ExtJSONValueWriterPool {
return &ExtJSONValueWriterPool{
pool: sync.Pool{
New: func() interface{} {
return new(extJSONValueWriter)
},
},
}
}
// Get retrieves a ExtJSON ValueWriter from the pool and resets it to use w as the destination.
func (bvwp *ExtJSONValueWriterPool) Get(w io.Writer, canonical, escapeHTML bool) ValueWriter {
vw := bvwp.pool.Get().(*extJSONValueWriter)
if writer, ok := w.(*SliceWriter); ok {
vw.reset(*writer, canonical, escapeHTML)
vw.w = writer
return vw
}
vw.buf = vw.buf[:0]
vw.w = w
return vw
}
// Put inserts a ValueWriter into the pool. If the ValueWriter is not a ExtJSON ValueWriter, nothing
// happens and ok will be false.
func (bvwp *ExtJSONValueWriterPool) Put(vw ValueWriter) (ok bool) {
bvw, ok := vw.(*extJSONValueWriter)
if !ok {
return false
}
if _, ok := bvw.w.(*SliceWriter); ok {
bvw.buf = nil
}
bvw.w = nil
bvwp.pool.Put(bvw)
return true
}
type ejvwState struct {
mode mode
}
type extJSONValueWriter struct {
w io.Writer
buf []byte
stack []ejvwState
frame int64
canonical bool
escapeHTML bool
}
// NewExtJSONValueWriter creates a ValueWriter that writes Extended JSON to w.
func NewExtJSONValueWriter(w io.Writer, canonical, escapeHTML bool) (ValueWriter, error) {
if w == nil {
return nil, errNilWriter
}
return newExtJSONWriter(w, canonical, escapeHTML), nil
}
func newExtJSONWriter(w io.Writer, canonical, escapeHTML bool) *extJSONValueWriter {
stack := make([]ejvwState, 1, 5)
stack[0] = ejvwState{mode: mTopLevel}
return &extJSONValueWriter{
w: w,
buf: []byte{},
stack: stack,
canonical: canonical,
escapeHTML: escapeHTML,
}
}
func newExtJSONWriterFromSlice(buf []byte, canonical, escapeHTML bool) *extJSONValueWriter {
stack := make([]ejvwState, 1, 5)
stack[0] = ejvwState{mode: mTopLevel}
return &extJSONValueWriter{
buf: buf,
stack: stack,
canonical: canonical,
escapeHTML: escapeHTML,
}
}
func (ejvw *extJSONValueWriter) reset(buf []byte, canonical, escapeHTML bool) {
if ejvw.stack == nil {
ejvw.stack = make([]ejvwState, 1, 5)
}
ejvw.stack = ejvw.stack[:1]
ejvw.stack[0] = ejvwState{mode: mTopLevel}
ejvw.canonical = canonical
ejvw.escapeHTML = escapeHTML
ejvw.frame = 0
ejvw.buf = buf
ejvw.w = nil
}
func (ejvw *extJSONValueWriter) advanceFrame() {
if ejvw.frame+1 >= int64(len(ejvw.stack)) { // We need to grow the stack
length := len(ejvw.stack)
if length+1 >= cap(ejvw.stack) {
// double it
buf := make([]ejvwState, 2*cap(ejvw.stack)+1)
copy(buf, ejvw.stack)
ejvw.stack = buf
}
ejvw.stack = ejvw.stack[:length+1]
}
ejvw.frame++
}
func (ejvw *extJSONValueWriter) push(m mode) {
ejvw.advanceFrame()
ejvw.stack[ejvw.frame].mode = m
}
func (ejvw *extJSONValueWriter) pop() {
switch ejvw.stack[ejvw.frame].mode {
case mElement, mValue:
ejvw.frame--
case mDocument, mArray, mCodeWithScope:
ejvw.frame -= 2 // we pop twice to jump over the mElement: mDocument -> mElement -> mDocument/mTopLevel/etc...
}
}
func (ejvw *extJSONValueWriter) invalidTransitionErr(destination mode, name string, modes []mode) error {
te := TransitionError{
name: name,
current: ejvw.stack[ejvw.frame].mode,
destination: destination,
modes: modes,
action: "write",
}
if ejvw.frame != 0 {
te.parent = ejvw.stack[ejvw.frame-1].mode
}
return te
}
func (ejvw *extJSONValueWriter) ensureElementValue(destination mode, callerName string, addmodes ...mode) error {
switch ejvw.stack[ejvw.frame].mode {
case mElement, mValue:
default:
modes := []mode{mElement, mValue}
if addmodes != nil {
modes = append(modes, addmodes...)
}
return ejvw.invalidTransitionErr(destination, callerName, modes)
}
return nil
}
func (ejvw *extJSONValueWriter) writeExtendedSingleValue(key string, value string, quotes bool) {
var s string
if quotes {
s = fmt.Sprintf(`{"$%s":"%s"}`, key, value)
} else {
s = fmt.Sprintf(`{"$%s":%s}`, key, value)
}
ejvw.buf = append(ejvw.buf, []byte(s)...)
}
func (ejvw *extJSONValueWriter) WriteArray() (ArrayWriter, error) {
if err := ejvw.ensureElementValue(mArray, "WriteArray"); err != nil {
return nil, err
}
ejvw.buf = append(ejvw.buf, '[')
ejvw.push(mArray)
return ejvw, nil
}
func (ejvw *extJSONValueWriter) WriteBinary(b []byte) error {
return ejvw.WriteBinaryWithSubtype(b, 0x00)
}
func (ejvw *extJSONValueWriter) WriteBinaryWithSubtype(b []byte, btype byte) error {
if err := ejvw.ensureElementValue(mode(0), "WriteBinaryWithSubtype"); err != nil {
return err
}
var buf bytes.Buffer
buf.WriteString(`{"$binary":{"base64":"`)
buf.WriteString(base64.StdEncoding.EncodeToString(b))
buf.WriteString(fmt.Sprintf(`","subType":"%02x"}},`, btype))
ejvw.buf = append(ejvw.buf, buf.Bytes()...)
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteBoolean(b bool) error {
if err := ejvw.ensureElementValue(mode(0), "WriteBoolean"); err != nil {
return err
}
ejvw.buf = append(ejvw.buf, []byte(strconv.FormatBool(b))...)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteCodeWithScope(code string) (DocumentWriter, error) {
if err := ejvw.ensureElementValue(mCodeWithScope, "WriteCodeWithScope"); err != nil {
return nil, err
}
var buf bytes.Buffer
buf.WriteString(`{"$code":`)
writeStringWithEscapes(code, &buf, ejvw.escapeHTML)
buf.WriteString(`,"$scope":{`)
ejvw.buf = append(ejvw.buf, buf.Bytes()...)
ejvw.push(mCodeWithScope)
return ejvw, nil
}
func (ejvw *extJSONValueWriter) WriteDBPointer(ns string, oid primitive.ObjectID) error {
if err := ejvw.ensureElementValue(mode(0), "WriteDBPointer"); err != nil {
return err
}
var buf bytes.Buffer
buf.WriteString(`{"$dbPointer":{"$ref":"`)
buf.WriteString(ns)
buf.WriteString(`","$id":{"$oid":"`)
buf.WriteString(oid.Hex())
buf.WriteString(`"}}},`)
ejvw.buf = append(ejvw.buf, buf.Bytes()...)
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteDateTime(dt int64) error {
if err := ejvw.ensureElementValue(mode(0), "WriteDateTime"); err != nil {
return err
}
t := time.Unix(dt/1e3, dt%1e3*1e6).UTC()
if ejvw.canonical || t.Year() < 1970 || t.Year() > 9999 {
s := fmt.Sprintf(`{"$numberLong":"%d"}`, dt)
ejvw.writeExtendedSingleValue("date", s, false)
} else {
ejvw.writeExtendedSingleValue("date", t.Format(rfc3339Milli), true)
}
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteDecimal128(d primitive.Decimal128) error {
if err := ejvw.ensureElementValue(mode(0), "WriteDecimal128"); err != nil {
return err
}
ejvw.writeExtendedSingleValue("numberDecimal", d.String(), true)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteDocument() (DocumentWriter, error) {
if ejvw.stack[ejvw.frame].mode == mTopLevel {
ejvw.buf = append(ejvw.buf, '{')
return ejvw, nil
}
if err := ejvw.ensureElementValue(mDocument, "WriteDocument", mTopLevel); err != nil {
return nil, err
}
ejvw.buf = append(ejvw.buf, '{')
ejvw.push(mDocument)
return ejvw, nil
}
func (ejvw *extJSONValueWriter) WriteDouble(f float64) error {
if err := ejvw.ensureElementValue(mode(0), "WriteDouble"); err != nil {
return err
}
s := formatDouble(f)
if ejvw.canonical {
ejvw.writeExtendedSingleValue("numberDouble", s, true)
} else {
switch s {
case "Infinity":
fallthrough
case "-Infinity":
fallthrough
case "NaN":
s = fmt.Sprintf(`{"$numberDouble":"%s"}`, s)
}
ejvw.buf = append(ejvw.buf, []byte(s)...)
}
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteInt32(i int32) error {
if err := ejvw.ensureElementValue(mode(0), "WriteInt32"); err != nil {
return err
}
s := strconv.FormatInt(int64(i), 10)
if ejvw.canonical {
ejvw.writeExtendedSingleValue("numberInt", s, true)
} else {
ejvw.buf = append(ejvw.buf, []byte(s)...)
}
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteInt64(i int64) error {
if err := ejvw.ensureElementValue(mode(0), "WriteInt64"); err != nil {
return err
}
s := strconv.FormatInt(i, 10)
if ejvw.canonical {
ejvw.writeExtendedSingleValue("numberLong", s, true)
} else {
ejvw.buf = append(ejvw.buf, []byte(s)...)
}
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteJavascript(code string) error {
if err := ejvw.ensureElementValue(mode(0), "WriteJavascript"); err != nil {
return err
}
var buf bytes.Buffer
writeStringWithEscapes(code, &buf, ejvw.escapeHTML)
ejvw.writeExtendedSingleValue("code", buf.String(), false)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteMaxKey() error {
if err := ejvw.ensureElementValue(mode(0), "WriteMaxKey"); err != nil {
return err
}
ejvw.writeExtendedSingleValue("maxKey", "1", false)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteMinKey() error {
if err := ejvw.ensureElementValue(mode(0), "WriteMinKey"); err != nil {
return err
}
ejvw.writeExtendedSingleValue("minKey", "1", false)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteNull() error {
if err := ejvw.ensureElementValue(mode(0), "WriteNull"); err != nil {
return err
}
ejvw.buf = append(ejvw.buf, []byte("null")...)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteObjectID(oid primitive.ObjectID) error {
if err := ejvw.ensureElementValue(mode(0), "WriteObjectID"); err != nil {
return err
}
ejvw.writeExtendedSingleValue("oid", oid.Hex(), true)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteRegex(pattern string, options string) error {
if err := ejvw.ensureElementValue(mode(0), "WriteRegex"); err != nil {
return err
}
var buf bytes.Buffer
buf.WriteString(`{"$regularExpression":{"pattern":`)
writeStringWithEscapes(pattern, &buf, ejvw.escapeHTML)
buf.WriteString(`,"options":"`)
buf.WriteString(sortStringAlphebeticAscending(options))
buf.WriteString(`"}},`)
ejvw.buf = append(ejvw.buf, buf.Bytes()...)
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteString(s string) error {
if err := ejvw.ensureElementValue(mode(0), "WriteString"); err != nil {
return err
}
var buf bytes.Buffer
writeStringWithEscapes(s, &buf, ejvw.escapeHTML)
ejvw.buf = append(ejvw.buf, buf.Bytes()...)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteSymbol(symbol string) error {
if err := ejvw.ensureElementValue(mode(0), "WriteSymbol"); err != nil {
return err
}
var buf bytes.Buffer
writeStringWithEscapes(symbol, &buf, ejvw.escapeHTML)
ejvw.writeExtendedSingleValue("symbol", buf.String(), false)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteTimestamp(t uint32, i uint32) error {
if err := ejvw.ensureElementValue(mode(0), "WriteTimestamp"); err != nil {
return err
}
var buf bytes.Buffer
buf.WriteString(`{"$timestamp":{"t":`)
buf.WriteString(strconv.FormatUint(uint64(t), 10))
buf.WriteString(`,"i":`)
buf.WriteString(strconv.FormatUint(uint64(i), 10))
buf.WriteString(`}},`)
ejvw.buf = append(ejvw.buf, buf.Bytes()...)
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteUndefined() error {
if err := ejvw.ensureElementValue(mode(0), "WriteUndefined"); err != nil {
return err
}
ejvw.writeExtendedSingleValue("undefined", "true", false)
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteDocumentElement(key string) (ValueWriter, error) {
switch ejvw.stack[ejvw.frame].mode {
case mDocument, mTopLevel, mCodeWithScope:
ejvw.buf = append(ejvw.buf, []byte(fmt.Sprintf(`"%s":`, key))...)
ejvw.push(mElement)
default:
return nil, ejvw.invalidTransitionErr(mElement, "WriteDocumentElement", []mode{mDocument, mTopLevel, mCodeWithScope})
}
return ejvw, nil
}
func (ejvw *extJSONValueWriter) WriteDocumentEnd() error {
switch ejvw.stack[ejvw.frame].mode {
case mDocument, mTopLevel, mCodeWithScope:
default:
return fmt.Errorf("incorrect mode to end document: %s", ejvw.stack[ejvw.frame].mode)
}
// close the document
if ejvw.buf[len(ejvw.buf)-1] == ',' {
ejvw.buf[len(ejvw.buf)-1] = '}'
} else {
ejvw.buf = append(ejvw.buf, '}')
}
switch ejvw.stack[ejvw.frame].mode {
case mCodeWithScope:
ejvw.buf = append(ejvw.buf, '}')
fallthrough
case mDocument:
ejvw.buf = append(ejvw.buf, ',')
case mTopLevel:
if ejvw.w != nil {
if _, err := ejvw.w.Write(ejvw.buf); err != nil {
return err
}
ejvw.buf = ejvw.buf[:0]
}
}
ejvw.pop()
return nil
}
func (ejvw *extJSONValueWriter) WriteArrayElement() (ValueWriter, error) {
switch ejvw.stack[ejvw.frame].mode {
case mArray:
ejvw.push(mValue)
default:
return nil, ejvw.invalidTransitionErr(mValue, "WriteArrayElement", []mode{mArray})
}
return ejvw, nil
}
func (ejvw *extJSONValueWriter) WriteArrayEnd() error {
switch ejvw.stack[ejvw.frame].mode {
case mArray:
// close the array
if ejvw.buf[len(ejvw.buf)-1] == ',' {
ejvw.buf[len(ejvw.buf)-1] = ']'
} else {
ejvw.buf = append(ejvw.buf, ']')
}
ejvw.buf = append(ejvw.buf, ',')
ejvw.pop()
default:
return fmt.Errorf("incorrect mode to end array: %s", ejvw.stack[ejvw.frame].mode)
}
return nil
}
func formatDouble(f float64) string {
var s string
if math.IsInf(f, 1) {
s = "Infinity"
} else if math.IsInf(f, -1) {
s = "-Infinity"
} else if math.IsNaN(f) {
s = "NaN"
} else {
// Print exactly one decimalType place for integers; otherwise, print as many are necessary to
// perfectly represent it.
s = strconv.FormatFloat(f, 'G', -1, 64)
if !strings.ContainsRune(s, 'E') && !strings.ContainsRune(s, '.') {
s += ".0"
}
}
return s
}
var hexChars = "0123456789abcdef"
func writeStringWithEscapes(s string, buf *bytes.Buffer, escapeHTML bool) {
buf.WriteByte('"')
start := 0
for i := 0; i < len(s); {
if b := s[i]; b < utf8.RuneSelf {
if htmlSafeSet[b] || (!escapeHTML && safeSet[b]) {
i++
continue
}
if start < i {
buf.WriteString(s[start:i])
}
switch b {
case '\\', '"':
buf.WriteByte('\\')
buf.WriteByte(b)
case '\n':
buf.WriteByte('\\')
buf.WriteByte('n')
case '\r':
buf.WriteByte('\\')
buf.WriteByte('r')
case '\t':
buf.WriteByte('\\')
buf.WriteByte('t')
case '\b':
buf.WriteByte('\\')
buf.WriteByte('b')
case '\f':
buf.WriteByte('\\')
buf.WriteByte('f')
default:
// This encodes bytes < 0x20 except for \t, \n and \r.
// If escapeHTML is set, it also escapes <, >, and &
// because they can lead to security holes when
// user-controlled strings are rendered into JSON
// and served to some browsers.
buf.WriteString(`\u00`)
buf.WriteByte(hexChars[b>>4])
buf.WriteByte(hexChars[b&0xF])
}
i++
start = i
continue
}
c, size := utf8.DecodeRuneInString(s[i:])
if c == utf8.RuneError && size == 1 {
if start < i {
buf.WriteString(s[start:i])
}
buf.WriteString(`\ufffd`)
i += size
start = i
continue
}
// U+2028 is LINE SEPARATOR.
// U+2029 is PARAGRAPH SEPARATOR.
// They are both technically valid characters in JSON strings,
// but don't work in JSONP, which has to be evaluated as JavaScript,
// and can lead to security holes there. It is valid JSON to
// escape them, so we do so unconditionally.
// See http://timelessrepo.com/json-isnt-a-javascript-subset for discussion.
if c == '\u2028' || c == '\u2029' {
if start < i {
buf.WriteString(s[start:i])
}
buf.WriteString(`\u202`)
buf.WriteByte(hexChars[c&0xF])
i += size
start = i
continue
}
i += size
}
if start < len(s) {
buf.WriteString(s[start:])
}
buf.WriteByte('"')
}
type sortableString []rune
func (ss sortableString) Len() int {
return len(ss)
}
func (ss sortableString) Less(i, j int) bool {
return ss[i] < ss[j]
}
func (ss sortableString) Swap(i, j int) {
oldI := ss[i]
ss[i] = ss[j]
ss[j] = oldI
}
func sortStringAlphebeticAscending(s string) string {
ss := sortableString([]rune(s))
sort.Sort(ss)
return string([]rune(ss))
}