upstream-grpc-go/experimental/stats/telemetry/labels.go

/*
 *
 * Copyright 2026 gRPC 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 telemetry defines stats APIs for interacting with
// telemetry labels.
//
// # Experimental
//
// Notice: All APIs in this package are experimental and may be changed or
// removed in a later release.
package telemetry

import (
	"context"

	stats "google.golang.org/grpc/internal/stats"
)

// NewContextWithLabelCallback registers a callback function that is executed
// whenever telemetry labels are updated. This does _not_ require opentelemetry
// instrumentation to be configured on the client or server.
//
// WARNING: Callbacks are executed on the RPC path so users should be mindful
// of the potential performance impact when this is eventually executed.
func NewContextWithLabelCallback(ctx context.Context, callback stats.LabelCallback) context.Context {
	return stats.RegisterTelemetryLabelCallback(ctx, callback)
}