mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-12-05 18:12:46 +00:00
1019 lines
25 KiB
Go
1019 lines
25 KiB
Go
// Copyright The OpenTelemetry Authors
|
||
// SPDX-License-Identifier: Apache-2.0
|
||
|
||
package baggage // import "go.opentelemetry.io/otel/baggage"
|
||
|
||
import (
|
||
"errors"
|
||
"fmt"
|
||
"net/url"
|
||
"strings"
|
||
"unicode/utf8"
|
||
|
||
"go.opentelemetry.io/otel/internal/baggage"
|
||
)
|
||
|
||
const (
|
||
maxMembers = 180
|
||
maxBytesPerMembers = 4096
|
||
maxBytesPerBaggageString = 8192
|
||
|
||
listDelimiter = ","
|
||
keyValueDelimiter = "="
|
||
propertyDelimiter = ";"
|
||
)
|
||
|
||
var (
|
||
errInvalidKey = errors.New("invalid key")
|
||
errInvalidValue = errors.New("invalid value")
|
||
errInvalidProperty = errors.New("invalid baggage list-member property")
|
||
errInvalidMember = errors.New("invalid baggage list-member")
|
||
errMemberNumber = errors.New("too many list-members in baggage-string")
|
||
errMemberBytes = errors.New("list-member too large")
|
||
errBaggageBytes = errors.New("baggage-string too large")
|
||
)
|
||
|
||
// Property is an additional metadata entry for a baggage list-member.
|
||
type Property struct {
|
||
key, value string
|
||
|
||
// hasValue indicates if a zero-value value means the property does not
|
||
// have a value or if it was the zero-value.
|
||
hasValue bool
|
||
}
|
||
|
||
// NewKeyProperty returns a new Property for key.
|
||
//
|
||
// The passed key must be valid, non-empty UTF-8 string.
|
||
// If key is invalid, an error will be returned.
|
||
// However, the specific Propagators that are used to transmit baggage entries across
|
||
// component boundaries may impose their own restrictions on Property key.
|
||
// For example, the W3C Baggage specification restricts the Property keys to strings that
|
||
// satisfy the token definition from RFC7230, Section 3.2.6.
|
||
// For maximum compatibility, alpha-numeric value are strongly recommended to be used as Property key.
|
||
func NewKeyProperty(key string) (Property, error) {
|
||
if !validateBaggageName(key) {
|
||
return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
|
||
}
|
||
|
||
p := Property{key: key}
|
||
return p, nil
|
||
}
|
||
|
||
// NewKeyValueProperty returns a new Property for key with value.
|
||
//
|
||
// The passed key must be compliant with W3C Baggage specification.
|
||
// The passed value must be percent-encoded as defined in W3C Baggage specification.
|
||
//
|
||
// Notice: Consider using [NewKeyValuePropertyRaw] instead
|
||
// that does not require percent-encoding of the value.
|
||
func NewKeyValueProperty(key, value string) (Property, error) {
|
||
if !validateKey(key) {
|
||
return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
|
||
}
|
||
|
||
if !validateValue(value) {
|
||
return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidValue, value)
|
||
}
|
||
decodedValue, err := url.PathUnescape(value)
|
||
if err != nil {
|
||
return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidValue, value)
|
||
}
|
||
return NewKeyValuePropertyRaw(key, decodedValue)
|
||
}
|
||
|
||
// NewKeyValuePropertyRaw returns a new Property for key with value.
|
||
//
|
||
// The passed key must be valid, non-empty UTF-8 string.
|
||
// The passed value must be valid UTF-8 string.
|
||
// However, the specific Propagators that are used to transmit baggage entries across
|
||
// component boundaries may impose their own restrictions on Property key.
|
||
// For example, the W3C Baggage specification restricts the Property keys to strings that
|
||
// satisfy the token definition from RFC7230, Section 3.2.6.
|
||
// For maximum compatibility, alpha-numeric value are strongly recommended to be used as Property key.
|
||
func NewKeyValuePropertyRaw(key, value string) (Property, error) {
|
||
if !validateBaggageName(key) {
|
||
return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
|
||
}
|
||
if !validateBaggageValue(value) {
|
||
return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidValue, value)
|
||
}
|
||
|
||
p := Property{
|
||
key: key,
|
||
value: value,
|
||
hasValue: true,
|
||
}
|
||
return p, nil
|
||
}
|
||
|
||
func newInvalidProperty() Property {
|
||
return Property{}
|
||
}
|
||
|
||
// parseProperty attempts to decode a Property from the passed string. It
|
||
// returns an error if the input is invalid according to the W3C Baggage
|
||
// specification.
|
||
func parseProperty(property string) (Property, error) {
|
||
if property == "" {
|
||
return newInvalidProperty(), nil
|
||
}
|
||
|
||
p, ok := parsePropertyInternal(property)
|
||
if !ok {
|
||
return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidProperty, property)
|
||
}
|
||
|
||
return p, nil
|
||
}
|
||
|
||
// validate ensures p conforms to the W3C Baggage specification, returning an
|
||
// error otherwise.
|
||
func (p Property) validate() error {
|
||
errFunc := func(err error) error {
|
||
return fmt.Errorf("invalid property: %w", err)
|
||
}
|
||
|
||
if !validateBaggageName(p.key) {
|
||
return errFunc(fmt.Errorf("%w: %q", errInvalidKey, p.key))
|
||
}
|
||
if !p.hasValue && p.value != "" {
|
||
return errFunc(errors.New("inconsistent value"))
|
||
}
|
||
if p.hasValue && !validateBaggageValue(p.value) {
|
||
return errFunc(fmt.Errorf("%w: %q", errInvalidValue, p.value))
|
||
}
|
||
return nil
|
||
}
|
||
|
||
// Key returns the Property key.
|
||
func (p Property) Key() string {
|
||
return p.key
|
||
}
|
||
|
||
// Value returns the Property value. Additionally, a boolean value is returned
|
||
// indicating if the returned value is the empty if the Property has a value
|
||
// that is empty or if the value is not set.
|
||
func (p Property) Value() (string, bool) {
|
||
return p.value, p.hasValue
|
||
}
|
||
|
||
// String encodes Property into a header string compliant with the W3C Baggage
|
||
// specification.
|
||
// It would return empty string if the key is invalid with the W3C Baggage
|
||
// specification. This could happen for a UTF-8 key, as it may contain
|
||
// invalid characters.
|
||
func (p Property) String() string {
|
||
// W3C Baggage specification does not allow percent-encoded keys.
|
||
if !validateKey(p.key) {
|
||
return ""
|
||
}
|
||
|
||
if p.hasValue {
|
||
return fmt.Sprintf("%s%s%v", p.key, keyValueDelimiter, valueEscape(p.value))
|
||
}
|
||
return p.key
|
||
}
|
||
|
||
type properties []Property
|
||
|
||
func fromInternalProperties(iProps []baggage.Property) properties {
|
||
if len(iProps) == 0 {
|
||
return nil
|
||
}
|
||
|
||
props := make(properties, len(iProps))
|
||
for i, p := range iProps {
|
||
props[i] = Property{
|
||
key: p.Key,
|
||
value: p.Value,
|
||
hasValue: p.HasValue,
|
||
}
|
||
}
|
||
return props
|
||
}
|
||
|
||
func (p properties) asInternal() []baggage.Property {
|
||
if len(p) == 0 {
|
||
return nil
|
||
}
|
||
|
||
iProps := make([]baggage.Property, len(p))
|
||
for i, prop := range p {
|
||
iProps[i] = baggage.Property{
|
||
Key: prop.key,
|
||
Value: prop.value,
|
||
HasValue: prop.hasValue,
|
||
}
|
||
}
|
||
return iProps
|
||
}
|
||
|
||
func (p properties) Copy() properties {
|
||
if len(p) == 0 {
|
||
return nil
|
||
}
|
||
|
||
props := make(properties, len(p))
|
||
copy(props, p)
|
||
return props
|
||
}
|
||
|
||
// validate ensures each Property in p conforms to the W3C Baggage
|
||
// specification, returning an error otherwise.
|
||
func (p properties) validate() error {
|
||
for _, prop := range p {
|
||
if err := prop.validate(); err != nil {
|
||
return err
|
||
}
|
||
}
|
||
return nil
|
||
}
|
||
|
||
// String encodes properties into a header string compliant with the W3C Baggage
|
||
// specification.
|
||
func (p properties) String() string {
|
||
props := make([]string, 0, len(p))
|
||
for _, prop := range p {
|
||
s := prop.String()
|
||
|
||
// Ignored empty properties.
|
||
if s != "" {
|
||
props = append(props, s)
|
||
}
|
||
}
|
||
return strings.Join(props, propertyDelimiter)
|
||
}
|
||
|
||
// Member is a list-member of a baggage-string as defined by the W3C Baggage
|
||
// specification.
|
||
type Member struct {
|
||
key, value string
|
||
properties properties
|
||
|
||
// hasData indicates whether the created property contains data or not.
|
||
// Properties that do not contain data are invalid with no other check
|
||
// required.
|
||
hasData bool
|
||
}
|
||
|
||
// NewMember returns a new Member from the passed arguments.
|
||
//
|
||
// The passed key must be compliant with W3C Baggage specification.
|
||
// The passed value must be percent-encoded as defined in W3C Baggage specification.
|
||
//
|
||
// Notice: Consider using [NewMemberRaw] instead
|
||
// that does not require percent-encoding of the value.
|
||
func NewMember(key, value string, props ...Property) (Member, error) {
|
||
if !validateKey(key) {
|
||
return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidKey, key)
|
||
}
|
||
|
||
if !validateValue(value) {
|
||
return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidValue, value)
|
||
}
|
||
decodedValue, err := url.PathUnescape(value)
|
||
if err != nil {
|
||
return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidValue, value)
|
||
}
|
||
return NewMemberRaw(key, decodedValue, props...)
|
||
}
|
||
|
||
// NewMemberRaw returns a new Member from the passed arguments.
|
||
//
|
||
// The passed key must be valid, non-empty UTF-8 string.
|
||
// The passed value must be valid UTF-8 string.
|
||
// However, the specific Propagators that are used to transmit baggage entries across
|
||
// component boundaries may impose their own restrictions on baggage key.
|
||
// For example, the W3C Baggage specification restricts the baggage keys to strings that
|
||
// satisfy the token definition from RFC7230, Section 3.2.6.
|
||
// For maximum compatibility, alpha-numeric value are strongly recommended to be used as baggage key.
|
||
func NewMemberRaw(key, value string, props ...Property) (Member, error) {
|
||
m := Member{
|
||
key: key,
|
||
value: value,
|
||
properties: properties(props).Copy(),
|
||
hasData: true,
|
||
}
|
||
if err := m.validate(); err != nil {
|
||
return newInvalidMember(), err
|
||
}
|
||
return m, nil
|
||
}
|
||
|
||
func newInvalidMember() Member {
|
||
return Member{}
|
||
}
|
||
|
||
// parseMember attempts to decode a Member from the passed string. It returns
|
||
// an error if the input is invalid according to the W3C Baggage
|
||
// specification.
|
||
func parseMember(member string) (Member, error) {
|
||
if n := len(member); n > maxBytesPerMembers {
|
||
return newInvalidMember(), fmt.Errorf("%w: %d", errMemberBytes, n)
|
||
}
|
||
|
||
var props properties
|
||
keyValue, properties, found := strings.Cut(member, propertyDelimiter)
|
||
if found {
|
||
// Parse the member properties.
|
||
for _, pStr := range strings.Split(properties, propertyDelimiter) {
|
||
p, err := parseProperty(pStr)
|
||
if err != nil {
|
||
return newInvalidMember(), err
|
||
}
|
||
props = append(props, p)
|
||
}
|
||
}
|
||
// Parse the member key/value pair.
|
||
|
||
// Take into account a value can contain equal signs (=).
|
||
k, v, found := strings.Cut(keyValue, keyValueDelimiter)
|
||
if !found {
|
||
return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidMember, member)
|
||
}
|
||
// "Leading and trailing whitespaces are allowed but MUST be trimmed
|
||
// when converting the header into a data structure."
|
||
key := strings.TrimSpace(k)
|
||
if !validateKey(key) {
|
||
return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidKey, key)
|
||
}
|
||
|
||
rawVal := strings.TrimSpace(v)
|
||
if !validateValue(rawVal) {
|
||
return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidValue, v)
|
||
}
|
||
|
||
// Decode a percent-encoded value.
|
||
unescapeVal, err := url.PathUnescape(rawVal)
|
||
if err != nil {
|
||
return newInvalidMember(), fmt.Errorf("%w: %w", errInvalidValue, err)
|
||
}
|
||
|
||
value := replaceInvalidUTF8Sequences(len(rawVal), unescapeVal)
|
||
return Member{key: key, value: value, properties: props, hasData: true}, nil
|
||
}
|
||
|
||
// replaceInvalidUTF8Sequences replaces invalid UTF-8 sequences with '<27>'.
|
||
func replaceInvalidUTF8Sequences(cap int, unescapeVal string) string {
|
||
if utf8.ValidString(unescapeVal) {
|
||
return unescapeVal
|
||
}
|
||
// W3C baggage spec:
|
||
// https://github.com/w3c/baggage/blob/8c215efbeebd3fa4b1aceb937a747e56444f22f3/baggage/HTTP_HEADER_FORMAT.md?plain=1#L69
|
||
|
||
var b strings.Builder
|
||
b.Grow(cap)
|
||
for i := 0; i < len(unescapeVal); {
|
||
r, size := utf8.DecodeRuneInString(unescapeVal[i:])
|
||
if r == utf8.RuneError && size == 1 {
|
||
// Invalid UTF-8 sequence found, replace it with '<27>'
|
||
_, _ = b.WriteString("<22>")
|
||
} else {
|
||
_, _ = b.WriteRune(r)
|
||
}
|
||
i += size
|
||
}
|
||
|
||
return b.String()
|
||
}
|
||
|
||
// validate ensures m conforms to the W3C Baggage specification.
|
||
// A key must be an ASCII string, returning an error otherwise.
|
||
func (m Member) validate() error {
|
||
if !m.hasData {
|
||
return fmt.Errorf("%w: %q", errInvalidMember, m)
|
||
}
|
||
|
||
if !validateBaggageName(m.key) {
|
||
return fmt.Errorf("%w: %q", errInvalidKey, m.key)
|
||
}
|
||
if !validateBaggageValue(m.value) {
|
||
return fmt.Errorf("%w: %q", errInvalidValue, m.value)
|
||
}
|
||
return m.properties.validate()
|
||
}
|
||
|
||
// Key returns the Member key.
|
||
func (m Member) Key() string { return m.key }
|
||
|
||
// Value returns the Member value.
|
||
func (m Member) Value() string { return m.value }
|
||
|
||
// Properties returns a copy of the Member properties.
|
||
func (m Member) Properties() []Property { return m.properties.Copy() }
|
||
|
||
// String encodes Member into a header string compliant with the W3C Baggage
|
||
// specification.
|
||
// It would return empty string if the key is invalid with the W3C Baggage
|
||
// specification. This could happen for a UTF-8 key, as it may contain
|
||
// invalid characters.
|
||
func (m Member) String() string {
|
||
// W3C Baggage specification does not allow percent-encoded keys.
|
||
if !validateKey(m.key) {
|
||
return ""
|
||
}
|
||
|
||
s := m.key + keyValueDelimiter + valueEscape(m.value)
|
||
if len(m.properties) > 0 {
|
||
s += propertyDelimiter + m.properties.String()
|
||
}
|
||
return s
|
||
}
|
||
|
||
// Baggage is a list of baggage members representing the baggage-string as
|
||
// defined by the W3C Baggage specification.
|
||
type Baggage struct { //nolint:golint
|
||
list baggage.List
|
||
}
|
||
|
||
// New returns a new valid Baggage. It returns an error if it results in a
|
||
// Baggage exceeding limits set in that specification.
|
||
//
|
||
// It expects all the provided members to have already been validated.
|
||
func New(members ...Member) (Baggage, error) {
|
||
if len(members) == 0 {
|
||
return Baggage{}, nil
|
||
}
|
||
|
||
b := make(baggage.List)
|
||
for _, m := range members {
|
||
if !m.hasData {
|
||
return Baggage{}, errInvalidMember
|
||
}
|
||
|
||
// OpenTelemetry resolves duplicates by last-one-wins.
|
||
b[m.key] = baggage.Item{
|
||
Value: m.value,
|
||
Properties: m.properties.asInternal(),
|
||
}
|
||
}
|
||
|
||
// Check member numbers after deduplication.
|
||
if len(b) > maxMembers {
|
||
return Baggage{}, errMemberNumber
|
||
}
|
||
|
||
bag := Baggage{b}
|
||
if n := len(bag.String()); n > maxBytesPerBaggageString {
|
||
return Baggage{}, fmt.Errorf("%w: %d", errBaggageBytes, n)
|
||
}
|
||
|
||
return bag, nil
|
||
}
|
||
|
||
// Parse attempts to decode a baggage-string from the passed string. It
|
||
// returns an error if the input is invalid according to the W3C Baggage
|
||
// specification.
|
||
//
|
||
// If there are duplicate list-members contained in baggage, the last one
|
||
// defined (reading left-to-right) will be the only one kept. This diverges
|
||
// from the W3C Baggage specification which allows duplicate list-members, but
|
||
// conforms to the OpenTelemetry Baggage specification.
|
||
func Parse(bStr string) (Baggage, error) {
|
||
if bStr == "" {
|
||
return Baggage{}, nil
|
||
}
|
||
|
||
if n := len(bStr); n > maxBytesPerBaggageString {
|
||
return Baggage{}, fmt.Errorf("%w: %d", errBaggageBytes, n)
|
||
}
|
||
|
||
b := make(baggage.List)
|
||
for _, memberStr := range strings.Split(bStr, listDelimiter) {
|
||
m, err := parseMember(memberStr)
|
||
if err != nil {
|
||
return Baggage{}, err
|
||
}
|
||
// OpenTelemetry resolves duplicates by last-one-wins.
|
||
b[m.key] = baggage.Item{
|
||
Value: m.value,
|
||
Properties: m.properties.asInternal(),
|
||
}
|
||
}
|
||
|
||
// OpenTelemetry does not allow for duplicate list-members, but the W3C
|
||
// specification does. Now that we have deduplicated, ensure the baggage
|
||
// does not exceed list-member limits.
|
||
if len(b) > maxMembers {
|
||
return Baggage{}, errMemberNumber
|
||
}
|
||
|
||
return Baggage{b}, nil
|
||
}
|
||
|
||
// Member returns the baggage list-member identified by key.
|
||
//
|
||
// If there is no list-member matching the passed key the returned Member will
|
||
// be a zero-value Member.
|
||
// The returned member is not validated, as we assume the validation happened
|
||
// when it was added to the Baggage.
|
||
func (b Baggage) Member(key string) Member {
|
||
v, ok := b.list[key]
|
||
if !ok {
|
||
// We do not need to worry about distinguishing between the situation
|
||
// where a zero-valued Member is included in the Baggage because a
|
||
// zero-valued Member is invalid according to the W3C Baggage
|
||
// specification (it has an empty key).
|
||
return newInvalidMember()
|
||
}
|
||
|
||
return Member{
|
||
key: key,
|
||
value: v.Value,
|
||
properties: fromInternalProperties(v.Properties),
|
||
hasData: true,
|
||
}
|
||
}
|
||
|
||
// Members returns all the baggage list-members.
|
||
// The order of the returned list-members is not significant.
|
||
//
|
||
// The returned members are not validated, as we assume the validation happened
|
||
// when they were added to the Baggage.
|
||
func (b Baggage) Members() []Member {
|
||
if len(b.list) == 0 {
|
||
return nil
|
||
}
|
||
|
||
members := make([]Member, 0, len(b.list))
|
||
for k, v := range b.list {
|
||
members = append(members, Member{
|
||
key: k,
|
||
value: v.Value,
|
||
properties: fromInternalProperties(v.Properties),
|
||
hasData: true,
|
||
})
|
||
}
|
||
return members
|
||
}
|
||
|
||
// SetMember returns a copy of the Baggage with the member included. If the
|
||
// baggage contains a Member with the same key, the existing Member is
|
||
// replaced.
|
||
//
|
||
// If member is invalid according to the W3C Baggage specification, an error
|
||
// is returned with the original Baggage.
|
||
func (b Baggage) SetMember(member Member) (Baggage, error) {
|
||
if !member.hasData {
|
||
return b, errInvalidMember
|
||
}
|
||
|
||
n := len(b.list)
|
||
if _, ok := b.list[member.key]; !ok {
|
||
n++
|
||
}
|
||
list := make(baggage.List, n)
|
||
|
||
for k, v := range b.list {
|
||
// Do not copy if we are just going to overwrite.
|
||
if k == member.key {
|
||
continue
|
||
}
|
||
list[k] = v
|
||
}
|
||
|
||
list[member.key] = baggage.Item{
|
||
Value: member.value,
|
||
Properties: member.properties.asInternal(),
|
||
}
|
||
|
||
return Baggage{list: list}, nil
|
||
}
|
||
|
||
// DeleteMember returns a copy of the Baggage with the list-member identified
|
||
// by key removed.
|
||
func (b Baggage) DeleteMember(key string) Baggage {
|
||
n := len(b.list)
|
||
if _, ok := b.list[key]; ok {
|
||
n--
|
||
}
|
||
list := make(baggage.List, n)
|
||
|
||
for k, v := range b.list {
|
||
if k == key {
|
||
continue
|
||
}
|
||
list[k] = v
|
||
}
|
||
|
||
return Baggage{list: list}
|
||
}
|
||
|
||
// Len returns the number of list-members in the Baggage.
|
||
func (b Baggage) Len() int {
|
||
return len(b.list)
|
||
}
|
||
|
||
// String encodes Baggage into a header string compliant with the W3C Baggage
|
||
// specification.
|
||
// It would ignore members where the member key is invalid with the W3C Baggage
|
||
// specification. This could happen for a UTF-8 key, as it may contain
|
||
// invalid characters.
|
||
func (b Baggage) String() string {
|
||
members := make([]string, 0, len(b.list))
|
||
for k, v := range b.list {
|
||
s := Member{
|
||
key: k,
|
||
value: v.Value,
|
||
properties: fromInternalProperties(v.Properties),
|
||
}.String()
|
||
|
||
// Ignored empty members.
|
||
if s != "" {
|
||
members = append(members, s)
|
||
}
|
||
}
|
||
return strings.Join(members, listDelimiter)
|
||
}
|
||
|
||
// parsePropertyInternal attempts to decode a Property from the passed string.
|
||
// It follows the spec at https://www.w3.org/TR/baggage/#definition.
|
||
func parsePropertyInternal(s string) (p Property, ok bool) {
|
||
// For the entire function we will use " key = value " as an example.
|
||
// Attempting to parse the key.
|
||
// First skip spaces at the beginning "< >key = value " (they could be empty).
|
||
index := skipSpace(s, 0)
|
||
|
||
// Parse the key: " <key> = value ".
|
||
keyStart := index
|
||
keyEnd := index
|
||
for _, c := range s[keyStart:] {
|
||
if !validateKeyChar(c) {
|
||
break
|
||
}
|
||
keyEnd++
|
||
}
|
||
|
||
// If we couldn't find any valid key character,
|
||
// it means the key is either empty or invalid.
|
||
if keyStart == keyEnd {
|
||
return
|
||
}
|
||
|
||
// Skip spaces after the key: " key< >= value ".
|
||
index = skipSpace(s, keyEnd)
|
||
|
||
if index == len(s) {
|
||
// A key can have no value, like: " key ".
|
||
ok = true
|
||
p.key = s[keyStart:keyEnd]
|
||
return
|
||
}
|
||
|
||
// If we have not reached the end and we can't find the '=' delimiter,
|
||
// it means the property is invalid.
|
||
if s[index] != keyValueDelimiter[0] {
|
||
return
|
||
}
|
||
|
||
// Attempting to parse the value.
|
||
// Match: " key =< >value ".
|
||
index = skipSpace(s, index+1)
|
||
|
||
// Match the value string: " key = <value> ".
|
||
// A valid property can be: " key =".
|
||
// Therefore, we don't have to check if the value is empty.
|
||
valueStart := index
|
||
valueEnd := index
|
||
for _, c := range s[valueStart:] {
|
||
if !validateValueChar(c) {
|
||
break
|
||
}
|
||
valueEnd++
|
||
}
|
||
|
||
// Skip all trailing whitespaces: " key = value< >".
|
||
index = skipSpace(s, valueEnd)
|
||
|
||
// If after looking for the value and skipping whitespaces
|
||
// we have not reached the end, it means the property is
|
||
// invalid, something like: " key = value value1".
|
||
if index != len(s) {
|
||
return
|
||
}
|
||
|
||
// Decode a percent-encoded value.
|
||
rawVal := s[valueStart:valueEnd]
|
||
unescapeVal, err := url.PathUnescape(rawVal)
|
||
if err != nil {
|
||
return
|
||
}
|
||
value := replaceInvalidUTF8Sequences(len(rawVal), unescapeVal)
|
||
|
||
ok = true
|
||
p.key = s[keyStart:keyEnd]
|
||
p.hasValue = true
|
||
|
||
p.value = value
|
||
return
|
||
}
|
||
|
||
func skipSpace(s string, offset int) int {
|
||
i := offset
|
||
for ; i < len(s); i++ {
|
||
c := s[i]
|
||
if c != ' ' && c != '\t' {
|
||
break
|
||
}
|
||
}
|
||
return i
|
||
}
|
||
|
||
var safeKeyCharset = [utf8.RuneSelf]bool{
|
||
// 0x23 to 0x27
|
||
'#': true,
|
||
'$': true,
|
||
'%': true,
|
||
'&': true,
|
||
'\'': true,
|
||
|
||
// 0x30 to 0x39
|
||
'0': true,
|
||
'1': true,
|
||
'2': true,
|
||
'3': true,
|
||
'4': true,
|
||
'5': true,
|
||
'6': true,
|
||
'7': true,
|
||
'8': true,
|
||
'9': true,
|
||
|
||
// 0x41 to 0x5a
|
||
'A': true,
|
||
'B': true,
|
||
'C': true,
|
||
'D': true,
|
||
'E': true,
|
||
'F': true,
|
||
'G': true,
|
||
'H': true,
|
||
'I': true,
|
||
'J': true,
|
||
'K': true,
|
||
'L': true,
|
||
'M': true,
|
||
'N': true,
|
||
'O': true,
|
||
'P': true,
|
||
'Q': true,
|
||
'R': true,
|
||
'S': true,
|
||
'T': true,
|
||
'U': true,
|
||
'V': true,
|
||
'W': true,
|
||
'X': true,
|
||
'Y': true,
|
||
'Z': true,
|
||
|
||
// 0x5e to 0x7a
|
||
'^': true,
|
||
'_': true,
|
||
'`': true,
|
||
'a': true,
|
||
'b': true,
|
||
'c': true,
|
||
'd': true,
|
||
'e': true,
|
||
'f': true,
|
||
'g': true,
|
||
'h': true,
|
||
'i': true,
|
||
'j': true,
|
||
'k': true,
|
||
'l': true,
|
||
'm': true,
|
||
'n': true,
|
||
'o': true,
|
||
'p': true,
|
||
'q': true,
|
||
'r': true,
|
||
's': true,
|
||
't': true,
|
||
'u': true,
|
||
'v': true,
|
||
'w': true,
|
||
'x': true,
|
||
'y': true,
|
||
'z': true,
|
||
|
||
// remainder
|
||
'!': true,
|
||
'*': true,
|
||
'+': true,
|
||
'-': true,
|
||
'.': true,
|
||
'|': true,
|
||
'~': true,
|
||
}
|
||
|
||
// validateBaggageName checks if the string is a valid OpenTelemetry Baggage name.
|
||
// Baggage name is a valid, non-empty UTF-8 string.
|
||
func validateBaggageName(s string) bool {
|
||
if len(s) == 0 {
|
||
return false
|
||
}
|
||
|
||
return utf8.ValidString(s)
|
||
}
|
||
|
||
// validateBaggageValue checks if the string is a valid OpenTelemetry Baggage value.
|
||
// Baggage value is a valid UTF-8 strings.
|
||
// Empty string is also a valid UTF-8 string.
|
||
func validateBaggageValue(s string) bool {
|
||
return utf8.ValidString(s)
|
||
}
|
||
|
||
// validateKey checks if the string is a valid W3C Baggage key.
|
||
func validateKey(s string) bool {
|
||
if len(s) == 0 {
|
||
return false
|
||
}
|
||
|
||
for _, c := range s {
|
||
if !validateKeyChar(c) {
|
||
return false
|
||
}
|
||
}
|
||
|
||
return true
|
||
}
|
||
|
||
func validateKeyChar(c int32) bool {
|
||
return c >= 0 && c < int32(utf8.RuneSelf) && safeKeyCharset[c]
|
||
}
|
||
|
||
// validateValue checks if the string is a valid W3C Baggage value.
|
||
func validateValue(s string) bool {
|
||
for _, c := range s {
|
||
if !validateValueChar(c) {
|
||
return false
|
||
}
|
||
}
|
||
|
||
return true
|
||
}
|
||
|
||
var safeValueCharset = [utf8.RuneSelf]bool{
|
||
'!': true, // 0x21
|
||
|
||
// 0x23 to 0x2b
|
||
'#': true,
|
||
'$': true,
|
||
'%': true,
|
||
'&': true,
|
||
'\'': true,
|
||
'(': true,
|
||
')': true,
|
||
'*': true,
|
||
'+': true,
|
||
|
||
// 0x2d to 0x3a
|
||
'-': true,
|
||
'.': true,
|
||
'/': true,
|
||
'0': true,
|
||
'1': true,
|
||
'2': true,
|
||
'3': true,
|
||
'4': true,
|
||
'5': true,
|
||
'6': true,
|
||
'7': true,
|
||
'8': true,
|
||
'9': true,
|
||
':': true,
|
||
|
||
// 0x3c to 0x5b
|
||
'<': true, // 0x3C
|
||
'=': true, // 0x3D
|
||
'>': true, // 0x3E
|
||
'?': true, // 0x3F
|
||
'@': true, // 0x40
|
||
'A': true, // 0x41
|
||
'B': true, // 0x42
|
||
'C': true, // 0x43
|
||
'D': true, // 0x44
|
||
'E': true, // 0x45
|
||
'F': true, // 0x46
|
||
'G': true, // 0x47
|
||
'H': true, // 0x48
|
||
'I': true, // 0x49
|
||
'J': true, // 0x4A
|
||
'K': true, // 0x4B
|
||
'L': true, // 0x4C
|
||
'M': true, // 0x4D
|
||
'N': true, // 0x4E
|
||
'O': true, // 0x4F
|
||
'P': true, // 0x50
|
||
'Q': true, // 0x51
|
||
'R': true, // 0x52
|
||
'S': true, // 0x53
|
||
'T': true, // 0x54
|
||
'U': true, // 0x55
|
||
'V': true, // 0x56
|
||
'W': true, // 0x57
|
||
'X': true, // 0x58
|
||
'Y': true, // 0x59
|
||
'Z': true, // 0x5A
|
||
'[': true, // 0x5B
|
||
|
||
// 0x5d to 0x7e
|
||
']': true, // 0x5D
|
||
'^': true, // 0x5E
|
||
'_': true, // 0x5F
|
||
'`': true, // 0x60
|
||
'a': true, // 0x61
|
||
'b': true, // 0x62
|
||
'c': true, // 0x63
|
||
'd': true, // 0x64
|
||
'e': true, // 0x65
|
||
'f': true, // 0x66
|
||
'g': true, // 0x67
|
||
'h': true, // 0x68
|
||
'i': true, // 0x69
|
||
'j': true, // 0x6A
|
||
'k': true, // 0x6B
|
||
'l': true, // 0x6C
|
||
'm': true, // 0x6D
|
||
'n': true, // 0x6E
|
||
'o': true, // 0x6F
|
||
'p': true, // 0x70
|
||
'q': true, // 0x71
|
||
'r': true, // 0x72
|
||
's': true, // 0x73
|
||
't': true, // 0x74
|
||
'u': true, // 0x75
|
||
'v': true, // 0x76
|
||
'w': true, // 0x77
|
||
'x': true, // 0x78
|
||
'y': true, // 0x79
|
||
'z': true, // 0x7A
|
||
'{': true, // 0x7B
|
||
'|': true, // 0x7C
|
||
'}': true, // 0x7D
|
||
'~': true, // 0x7E
|
||
}
|
||
|
||
func validateValueChar(c int32) bool {
|
||
return c >= 0 && c < int32(utf8.RuneSelf) && safeValueCharset[c]
|
||
}
|
||
|
||
// valueEscape escapes the string so it can be safely placed inside a baggage value,
|
||
// replacing special characters with %XX sequences as needed.
|
||
//
|
||
// The implementation is based on:
|
||
// https://github.com/golang/go/blob/f6509cf5cdbb5787061b784973782933c47f1782/src/net/url/url.go#L285.
|
||
func valueEscape(s string) string {
|
||
hexCount := 0
|
||
for i := 0; i < len(s); i++ {
|
||
c := s[i]
|
||
if shouldEscape(c) {
|
||
hexCount++
|
||
}
|
||
}
|
||
|
||
if hexCount == 0 {
|
||
return s
|
||
}
|
||
|
||
var buf [64]byte
|
||
var t []byte
|
||
|
||
required := len(s) + 2*hexCount
|
||
if required <= len(buf) {
|
||
t = buf[:required]
|
||
} else {
|
||
t = make([]byte, required)
|
||
}
|
||
|
||
j := 0
|
||
for i := 0; i < len(s); i++ {
|
||
c := s[i]
|
||
if shouldEscape(s[i]) {
|
||
const upperhex = "0123456789ABCDEF"
|
||
t[j] = '%'
|
||
t[j+1] = upperhex[c>>4]
|
||
t[j+2] = upperhex[c&15]
|
||
j += 3
|
||
} else {
|
||
t[j] = c
|
||
j++
|
||
}
|
||
}
|
||
|
||
return string(t)
|
||
}
|
||
|
||
// shouldEscape returns true if the specified byte should be escaped when
|
||
// appearing in a baggage value string.
|
||
func shouldEscape(c byte) bool {
|
||
if c == '%' {
|
||
// The percent character must be encoded so that percent-encoding can work.
|
||
return true
|
||
}
|
||
return !validateValueChar(int32(c))
|
||
}
|