githaven-fork/vendor/go.opentelemetry.io/otel/propagation/propagation.go
6543 ac97ea573c
[Vendor] Update go-redis to v8.5.0 (#13749)
* Update go-redis to v8.4.0

* github.com/go-redis/redis/v8  v8.4.0 -> v8.5.0

* Apply suggestions from code review

Co-authored-by: zeripath <art27@cantab.net>

* TODO

* Use the Queue termination channel as the default context for pushes

Signed-off-by: Andrew Thornton <art27@cantab.net>

* missed one

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: zeripath <art27@cantab.net>
2021-02-10 21:28:32 +00:00

79 lines
2.7 KiB
Go
Vendored

// Copyright The OpenTelemetry Authors
//
// 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
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package propagation // import "go.opentelemetry.io/otel/propagation"
import "context"
// TextMapCarrier is the storage medium used by a TextMapPropagator.
type TextMapCarrier interface {
// Get returns the value associated with the passed key.
Get(key string) string
// Set stores the key-value pair.
Set(key string, value string)
}
// TextMapPropagator propagates cross-cutting concerns as key-value text
// pairs within a carrier that travels in-band across process boundaries.
type TextMapPropagator interface {
// Inject set cross-cutting concerns from the Context into the carrier.
Inject(ctx context.Context, carrier TextMapCarrier)
// Extract reads cross-cutting concerns from the carrier into a Context.
Extract(ctx context.Context, carrier TextMapCarrier) context.Context
// Fields returns the keys who's values are set with Inject.
Fields() []string
}
type compositeTextMapPropagator []TextMapPropagator
func (p compositeTextMapPropagator) Inject(ctx context.Context, carrier TextMapCarrier) {
for _, i := range p {
i.Inject(ctx, carrier)
}
}
func (p compositeTextMapPropagator) Extract(ctx context.Context, carrier TextMapCarrier) context.Context {
for _, i := range p {
ctx = i.Extract(ctx, carrier)
}
return ctx
}
func (p compositeTextMapPropagator) Fields() []string {
unique := make(map[string]struct{})
for _, i := range p {
for _, k := range i.Fields() {
unique[k] = struct{}{}
}
}
fields := make([]string, 0, len(unique))
for k := range unique {
fields = append(fields, k)
}
return fields
}
// NewCompositeTextMapPropagator returns a unified TextMapPropagator from the
// group of passed TextMapPropagator. This allows different cross-cutting
// concerns to be propagates in a unified manner.
//
// The returned TextMapPropagator will inject and extract cross-cutting
// concerns in the order the TextMapPropagators were provided. Additionally,
// the Fields method will return a de-duplicated slice of the keys that are
// set with the Inject method.
func NewCompositeTextMapPropagator(p ...TextMapPropagator) TextMapPropagator {
return compositeTextMapPropagator(p)
}