mirror of
https://github.com/superseriousbusiness/gotosocial.git
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5e871e81a8
* otel to 1.24 * prometheus exporter to 0.46 * bunotel to 1.1.17 Also: * Use schemaless URL for metrics * Add software version to tracing schema
745 lines
19 KiB
Go
745 lines
19 KiB
Go
// Copyright The OpenTelemetry Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package baggage // import "go.opentelemetry.io/otel/baggage"
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import (
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"errors"
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"fmt"
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"net/url"
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"strings"
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"go.opentelemetry.io/otel/internal/baggage"
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)
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const (
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maxMembers = 180
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maxBytesPerMembers = 4096
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maxBytesPerBaggageString = 8192
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listDelimiter = ","
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keyValueDelimiter = "="
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propertyDelimiter = ";"
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)
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var (
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errInvalidKey = errors.New("invalid key")
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errInvalidValue = errors.New("invalid value")
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errInvalidProperty = errors.New("invalid baggage list-member property")
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errInvalidMember = errors.New("invalid baggage list-member")
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errMemberNumber = errors.New("too many list-members in baggage-string")
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errMemberBytes = errors.New("list-member too large")
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errBaggageBytes = errors.New("baggage-string too large")
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)
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// Property is an additional metadata entry for a baggage list-member.
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type Property struct {
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key, value string
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// hasValue indicates if a zero-value value means the property does not
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// have a value or if it was the zero-value.
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hasValue bool
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}
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// NewKeyProperty returns a new Property for key.
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//
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// If key is invalid, an error will be returned.
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func NewKeyProperty(key string) (Property, error) {
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if !validateKey(key) {
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return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
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}
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p := Property{key: key}
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return p, nil
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}
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// NewKeyValueProperty returns a new Property for key with value.
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//
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// The passed key must be compliant with W3C Baggage specification.
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// The passed value must be precent-encoded as defined in W3C Baggage specification.
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//
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// Notice: Consider using [NewKeyValuePropertyRaw] instead
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// that does not require precent-encoding of the value.
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func NewKeyValueProperty(key, value string) (Property, error) {
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if !validateValue(value) {
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return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidValue, value)
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}
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decodedValue, err := url.PathUnescape(value)
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if err != nil {
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return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidValue, value)
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}
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return NewKeyValuePropertyRaw(key, decodedValue)
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}
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// NewKeyValuePropertyRaw returns a new Property for key with value.
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//
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// The passed key must be compliant with W3C Baggage specification.
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func NewKeyValuePropertyRaw(key, value string) (Property, error) {
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if !validateKey(key) {
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return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
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}
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p := Property{
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key: key,
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value: value,
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hasValue: true,
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}
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return p, nil
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}
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func newInvalidProperty() Property {
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return Property{}
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}
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// parseProperty attempts to decode a Property from the passed string. It
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// returns an error if the input is invalid according to the W3C Baggage
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// specification.
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func parseProperty(property string) (Property, error) {
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if property == "" {
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return newInvalidProperty(), nil
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}
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p, ok := parsePropertyInternal(property)
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if !ok {
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return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidProperty, property)
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}
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return p, nil
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}
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// validate ensures p conforms to the W3C Baggage specification, returning an
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// error otherwise.
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func (p Property) validate() error {
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errFunc := func(err error) error {
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return fmt.Errorf("invalid property: %w", err)
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}
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if !validateKey(p.key) {
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return errFunc(fmt.Errorf("%w: %q", errInvalidKey, p.key))
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}
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if !p.hasValue && p.value != "" {
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return errFunc(errors.New("inconsistent value"))
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}
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return nil
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}
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// Key returns the Property key.
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func (p Property) Key() string {
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return p.key
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}
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// Value returns the Property value. Additionally, a boolean value is returned
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// indicating if the returned value is the empty if the Property has a value
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// that is empty or if the value is not set.
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func (p Property) Value() (string, bool) {
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return p.value, p.hasValue
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}
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// String encodes Property into a header string compliant with the W3C Baggage
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// specification.
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func (p Property) String() string {
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if p.hasValue {
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return fmt.Sprintf("%s%s%v", p.key, keyValueDelimiter, valueEscape(p.value))
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}
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return p.key
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}
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type properties []Property
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func fromInternalProperties(iProps []baggage.Property) properties {
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if len(iProps) == 0 {
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return nil
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}
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props := make(properties, len(iProps))
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for i, p := range iProps {
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props[i] = Property{
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key: p.Key,
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value: p.Value,
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hasValue: p.HasValue,
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}
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}
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return props
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}
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func (p properties) asInternal() []baggage.Property {
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if len(p) == 0 {
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return nil
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}
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iProps := make([]baggage.Property, len(p))
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for i, prop := range p {
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iProps[i] = baggage.Property{
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Key: prop.key,
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Value: prop.value,
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HasValue: prop.hasValue,
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}
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}
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return iProps
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}
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func (p properties) Copy() properties {
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if len(p) == 0 {
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return nil
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}
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props := make(properties, len(p))
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copy(props, p)
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return props
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}
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// validate ensures each Property in p conforms to the W3C Baggage
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// specification, returning an error otherwise.
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func (p properties) validate() error {
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for _, prop := range p {
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if err := prop.validate(); err != nil {
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return err
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}
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}
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return nil
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}
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// String encodes properties into a header string compliant with the W3C Baggage
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// specification.
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func (p properties) String() string {
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props := make([]string, len(p))
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for i, prop := range p {
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props[i] = prop.String()
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}
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return strings.Join(props, propertyDelimiter)
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}
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// Member is a list-member of a baggage-string as defined by the W3C Baggage
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// specification.
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type Member struct {
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key, value string
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properties properties
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// hasData indicates whether the created property contains data or not.
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// Properties that do not contain data are invalid with no other check
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// required.
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hasData bool
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}
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// NewMemberRaw returns a new Member from the passed arguments.
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//
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// The passed key must be compliant with W3C Baggage specification.
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// The passed value must be precent-encoded as defined in W3C Baggage specification.
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//
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// Notice: Consider using [NewMemberRaw] instead
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// that does not require precent-encoding of the value.
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func NewMember(key, value string, props ...Property) (Member, error) {
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if !validateValue(value) {
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return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidValue, value)
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}
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decodedValue, err := url.PathUnescape(value)
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if err != nil {
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return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidValue, value)
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}
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return NewMemberRaw(key, decodedValue, props...)
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}
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// NewMemberRaw returns a new Member from the passed arguments.
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//
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// The passed key must be compliant with W3C Baggage specification.
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func NewMemberRaw(key, value string, props ...Property) (Member, error) {
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m := Member{
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key: key,
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value: value,
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properties: properties(props).Copy(),
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hasData: true,
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}
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if err := m.validate(); err != nil {
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return newInvalidMember(), err
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}
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return m, nil
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}
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func newInvalidMember() Member {
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return Member{}
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}
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// parseMember attempts to decode a Member from the passed string. It returns
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// an error if the input is invalid according to the W3C Baggage
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// specification.
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func parseMember(member string) (Member, error) {
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if n := len(member); n > maxBytesPerMembers {
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return newInvalidMember(), fmt.Errorf("%w: %d", errMemberBytes, n)
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}
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var props properties
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keyValue, properties, found := strings.Cut(member, propertyDelimiter)
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if found {
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// Parse the member properties.
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for _, pStr := range strings.Split(properties, propertyDelimiter) {
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p, err := parseProperty(pStr)
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if err != nil {
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return newInvalidMember(), err
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}
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props = append(props, p)
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}
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}
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// Parse the member key/value pair.
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// Take into account a value can contain equal signs (=).
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k, v, found := strings.Cut(keyValue, keyValueDelimiter)
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if !found {
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return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidMember, member)
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}
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// "Leading and trailing whitespaces are allowed but MUST be trimmed
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// when converting the header into a data structure."
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key := strings.TrimSpace(k)
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if !validateKey(key) {
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return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidKey, key)
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}
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val := strings.TrimSpace(v)
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if !validateValue(val) {
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return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidValue, v)
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}
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// Decode a precent-encoded value.
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value, err := url.PathUnescape(val)
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if err != nil {
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return newInvalidMember(), fmt.Errorf("%w: %v", errInvalidValue, err)
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}
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return Member{key: key, value: value, properties: props, hasData: true}, nil
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}
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// validate ensures m conforms to the W3C Baggage specification.
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// A key must be an ASCII string, returning an error otherwise.
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func (m Member) validate() error {
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if !m.hasData {
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return fmt.Errorf("%w: %q", errInvalidMember, m)
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}
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if !validateKey(m.key) {
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return fmt.Errorf("%w: %q", errInvalidKey, m.key)
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}
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return m.properties.validate()
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}
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// Key returns the Member key.
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func (m Member) Key() string { return m.key }
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// Value returns the Member value.
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func (m Member) Value() string { return m.value }
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// Properties returns a copy of the Member properties.
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func (m Member) Properties() []Property { return m.properties.Copy() }
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// String encodes Member into a header string compliant with the W3C Baggage
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// specification.
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func (m Member) String() string {
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// A key is just an ASCII string. A value is restricted to be
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// US-ASCII characters excluding CTLs, whitespace,
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// DQUOTE, comma, semicolon, and backslash.
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s := fmt.Sprintf("%s%s%s", m.key, keyValueDelimiter, valueEscape(m.value))
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if len(m.properties) > 0 {
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s = fmt.Sprintf("%s%s%s", s, propertyDelimiter, m.properties.String())
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}
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return s
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}
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// Baggage is a list of baggage members representing the baggage-string as
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// defined by the W3C Baggage specification.
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type Baggage struct { //nolint:golint
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list baggage.List
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}
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// New returns a new valid Baggage. It returns an error if it results in a
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// Baggage exceeding limits set in that specification.
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//
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// It expects all the provided members to have already been validated.
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func New(members ...Member) (Baggage, error) {
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if len(members) == 0 {
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return Baggage{}, nil
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}
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b := make(baggage.List)
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for _, m := range members {
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if !m.hasData {
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return Baggage{}, errInvalidMember
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}
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// OpenTelemetry resolves duplicates by last-one-wins.
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b[m.key] = baggage.Item{
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Value: m.value,
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Properties: m.properties.asInternal(),
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}
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}
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// Check member numbers after deduplication.
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if len(b) > maxMembers {
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return Baggage{}, errMemberNumber
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}
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bag := Baggage{b}
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if n := len(bag.String()); n > maxBytesPerBaggageString {
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return Baggage{}, fmt.Errorf("%w: %d", errBaggageBytes, n)
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}
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return bag, nil
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}
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// Parse attempts to decode a baggage-string from the passed string. It
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// returns an error if the input is invalid according to the W3C Baggage
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// specification.
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//
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// If there are duplicate list-members contained in baggage, the last one
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// defined (reading left-to-right) will be the only one kept. This diverges
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// from the W3C Baggage specification which allows duplicate list-members, but
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// conforms to the OpenTelemetry Baggage specification.
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func Parse(bStr string) (Baggage, error) {
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if bStr == "" {
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return Baggage{}, nil
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}
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if n := len(bStr); n > maxBytesPerBaggageString {
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return Baggage{}, fmt.Errorf("%w: %d", errBaggageBytes, n)
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}
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b := make(baggage.List)
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for _, memberStr := range strings.Split(bStr, listDelimiter) {
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m, err := parseMember(memberStr)
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if err != nil {
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return Baggage{}, err
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}
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// OpenTelemetry resolves duplicates by last-one-wins.
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b[m.key] = baggage.Item{
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Value: m.value,
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Properties: m.properties.asInternal(),
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}
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}
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// OpenTelemetry does not allow for duplicate list-members, but the W3C
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// specification does. Now that we have deduplicated, ensure the baggage
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// does not exceed list-member limits.
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if len(b) > maxMembers {
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return Baggage{}, errMemberNumber
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}
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return Baggage{b}, nil
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}
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// Member returns the baggage list-member identified by key.
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//
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// If there is no list-member matching the passed key the returned Member will
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// be a zero-value Member.
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// The returned member is not validated, as we assume the validation happened
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// when it was added to the Baggage.
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func (b Baggage) Member(key string) Member {
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v, ok := b.list[key]
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if !ok {
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// We do not need to worry about distinguishing between the situation
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// where a zero-valued Member is included in the Baggage because a
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// zero-valued Member is invalid according to the W3C Baggage
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// specification (it has an empty key).
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return newInvalidMember()
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}
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return Member{
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key: key,
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value: v.Value,
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properties: fromInternalProperties(v.Properties),
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hasData: true,
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}
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}
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// Members returns all the baggage list-members.
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// The order of the returned list-members does not have significance.
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//
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// The returned members are not validated, as we assume the validation happened
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// when they were added to the Baggage.
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func (b Baggage) Members() []Member {
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if len(b.list) == 0 {
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return nil
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}
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members := make([]Member, 0, len(b.list))
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for k, v := range b.list {
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members = append(members, Member{
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key: k,
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value: v.Value,
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properties: fromInternalProperties(v.Properties),
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hasData: true,
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})
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}
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return members
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}
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// SetMember returns a copy the Baggage with the member included. If the
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// baggage contains a Member with the same key the existing Member is
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// replaced.
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//
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// If member is invalid according to the W3C Baggage specification, an error
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// is returned with the original Baggage.
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func (b Baggage) SetMember(member Member) (Baggage, error) {
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if !member.hasData {
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return b, errInvalidMember
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}
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n := len(b.list)
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if _, ok := b.list[member.key]; !ok {
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n++
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}
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list := make(baggage.List, n)
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for k, v := range b.list {
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// Do not copy if we are just going to overwrite.
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if k == member.key {
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continue
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}
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list[k] = v
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}
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list[member.key] = baggage.Item{
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Value: member.value,
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Properties: member.properties.asInternal(),
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}
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return Baggage{list: list}, nil
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}
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// DeleteMember returns a copy of the Baggage with the list-member identified
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// by key removed.
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func (b Baggage) DeleteMember(key string) Baggage {
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n := len(b.list)
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if _, ok := b.list[key]; ok {
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n--
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}
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list := make(baggage.List, n)
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for k, v := range b.list {
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if k == key {
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continue
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}
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list[k] = v
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}
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return Baggage{list: list}
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}
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// Len returns the number of list-members in the Baggage.
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func (b Baggage) Len() int {
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return len(b.list)
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}
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// String encodes Baggage into a header string compliant with the W3C Baggage
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// specification.
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func (b Baggage) String() string {
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members := make([]string, 0, len(b.list))
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for k, v := range b.list {
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members = append(members, Member{
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key: k,
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value: v.Value,
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properties: fromInternalProperties(v.Properties),
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}.String())
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}
|
|
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 precent-encoded value.
|
|
value, err := url.PathUnescape(s[valueStart:valueEnd])
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
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
|
|
}
|
|
|
|
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 >= 0x23 && c <= 0x27) ||
|
|
(c >= 0x30 && c <= 0x39) ||
|
|
(c >= 0x41 && c <= 0x5a) ||
|
|
(c >= 0x5e && c <= 0x7a) ||
|
|
c == 0x21 ||
|
|
c == 0x2a ||
|
|
c == 0x2b ||
|
|
c == 0x2d ||
|
|
c == 0x2e ||
|
|
c == 0x7c ||
|
|
c == 0x7e
|
|
}
|
|
|
|
func validateValue(s string) bool {
|
|
for _, c := range s {
|
|
if !validateValueChar(c) {
|
|
return false
|
|
}
|
|
}
|
|
|
|
return true
|
|
}
|
|
|
|
func validateValueChar(c int32) bool {
|
|
return c == 0x21 ||
|
|
(c >= 0x23 && c <= 0x2b) ||
|
|
(c >= 0x2d && c <= 0x3a) ||
|
|
(c >= 0x3c && c <= 0x5b) ||
|
|
(c >= 0x5d && c <= 0x7e)
|
|
}
|
|
|
|
// 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))
|
|
}
|