diff --git a/packages/opentelemetry-types/src/context/propagation/Propagator.ts b/packages/opentelemetry-types/src/context/propagation/Propagator.ts new file mode 100644 index 0000000000..100e6960c2 --- /dev/null +++ b/packages/opentelemetry-types/src/context/propagation/Propagator.ts @@ -0,0 +1,43 @@ +/** + * Copyright 2019, 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 + * + * https://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. + */ + +import { SpanContext } from '../../trace/span_context'; + +/** Defines a Propagator interface. */ +export interface Propagator { + /** + * Injects the given {@link SpanContext} instance to transmit over the wire. + * + * OpenTelemetry defines a common set of format values (BinaryFormat and + * HTTPTextFormat), and each has an expected `carrier` type. + * + * @param spanContext the SpanContext to transmit over the wire. + * @param format the format of the carrier. + * @param carrier the carrier of propagation fields, such as an http request. + */ + inject(spanContext: SpanContext, format: string, carrier: unknown): void; + + /** + * Returns a {@link SpanContext} instance extracted from `carrier` in the + * given format from upstream. + * + * @param format the format of the carrier. + * @param carrier the carrier of propagation fields, such as an http request. + * @returns SpanContext The extracted SpanContext, or null if no such + * SpanContext could be found in carrier. + */ + extract(format: string, carrier: unknown): SpanContext | null; +} diff --git a/packages/opentelemetry-types/src/index.ts b/packages/opentelemetry-types/src/index.ts index e5e6cd025b..c40510842c 100644 --- a/packages/opentelemetry-types/src/index.ts +++ b/packages/opentelemetry-types/src/index.ts @@ -14,6 +14,7 @@ * limitations under the License. */ +export * from './context/propagation/Propagator'; export * from './resources/Resource'; export * from './trace/attributes'; export * from './trace/link';