Separate context propagation (OTEP 66)

.circleci/config.yml

@@ -160,6 +160,8 @@ jobs:
   lint_&_docs:
     docker:
       - image: node:12
+        environment:
+          NPM_CONFIG_UNSAFE_PERM: true
     steps:
       - checkout
       - run:
@@ -171,6 +173,9 @@ jobs:
       - run:
           name: Check code style and linting
           command: npm run check
+      - run:
+          name: Install API dependencies
+          command: lerna bootstrap --scope @opentelemetry/api --include-filtered-dependencies
       - run:
           name: Docs tests
           command: npm run docs-test

packages/opentelemetry-api/package.json

@@ -45,6 +45,9 @@
   "publishConfig": {
     "access": "public"
   },
+  "dependencies": {
+    "@opentelemetry/scope-base": "^0.4.0"
+  },
   "devDependencies": {
     "@types/mocha": "^5.2.7",
     "@types/node": "^12.6.8",

packages/opentelemetry-api/src/context/propagation/HttpTextFormat.ts

@@ -14,39 +14,35 @@
  * limitations under the License.
  */
 
-import { SpanContext } from '../../trace/span_context';
+import { Context } from '@opentelemetry/scope-base';
+import { Carrier } from './carrier';
 
 /**
- * Injects and extracts a value as text into carriers that travel in-band
- * across process boundaries. Encoding is expected to conform to the HTTP
+ * Injects {@link Context} into and extracts it from carriers that travel
+ * in-band across process boundaries. Encoding is expected to conform to the HTTP
  * Header Field semantics. Values are often encoded as RPC/HTTP request headers.
  *
  * The carrier of propagated data on both the client (injector) and server
- * (extractor) side is usually an http request. Propagation is usually
- * implemented via library- specific request interceptors, where the
- * client-side injects values and the server-side extracts them.
+ * (extractor) side is usually an object such as http headers.
  */
 export interface HttpTextFormat {
   /**
-   * Injects the given {@link SpanContext} instance to transmit over the wire.
+   * Injects values from a given {@link Context} into a carrier.
    *
    * 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.
+   * @param context the Context from which to extract values to transmit over the wire.
+   * @param carrier the carrier of propagation fields, such as http request headers.
    */
-  inject(spanContext: SpanContext, format: string, carrier: unknown): void;
+  inject(context: Context, carrier: Carrier): void;
 
   /**
-   * Returns a {@link SpanContext} instance extracted from `carrier` in the
-   * given format from upstream.
+   * Given a {@link Context} and a carrier, extract context values from a carrier and
+   * return a new context, created from the old context, with the extracted values.
    *
-   * @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.
+   * @param context the Context from which to extract values to transmit over the wire.
+   * @param carrier the carrier of propagation fields, such as http request headers.
    */
-  extract(format: string, carrier: unknown): SpanContext | null;
+  extract(context: Context, carrier: Carrier): Context;
 }

packages/opentelemetry-api/src/context/propagation/NoopHttpTextFormat.ts

@@ -14,18 +14,19 @@
  * limitations under the License.
  */
 
-import { SpanContext } from '../../trace/span_context';
+import { Context } from '@opentelemetry/scope-base';
+import { Carrier } from './carrier';
 import { HttpTextFormat } from './HttpTextFormat';
 
 /**
  * No-op implementations of {@link HttpTextFormat}.
  */
 export class NoopHttpTextFormat implements HttpTextFormat {
-  // By default does nothing
-  inject(spanContext: SpanContext, format: string, carrier: unknown): void {}
-  // By default does nothing
-  extract(format: string, carrier: unknown): SpanContext | null {
-    return null;
+  /** Noop inject function does nothing */
+  inject(context: Context, carrier: Carrier): void {}
+  /** Noop extract function does nothing and returns the input context */
+  extract(context: Context, carrier: Carrier): Context {
+    return context;
   }
 }
 

packages/opentelemetry-api/src/context/propagation/carrier.ts

@@ -0,0 +1,19 @@
+/*!
+ * Copyright 2020, 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.
+ */
+
+export type Carrier = {
+  [key: string]: unknown;
+};

packages/opentelemetry-api/src/index.ts

@@ -17,33 +17,32 @@
 export * from './common/Logger';
 export * from './common/Time';
 export * from './context/propagation/BinaryFormat';
+export * from './context/propagation/carrier';
 export * from './context/propagation/HttpTextFormat';
-export * from './distributed_context/DistributedContext';
-export * from './distributed_context/EntryValue';
 export * from './metrics/BoundInstrument';
 export * from './metrics/Meter';
 export * from './metrics/MeterProvider';
 export * from './metrics/Metric';
+export * from './metrics/NoopMeter';
+export * from './metrics/NoopMeterProvider';
 export * from './trace/attributes';
 export * from './trace/Event';
 export * from './trace/instrumentation/Plugin';
 export * from './trace/link';
+export * from './trace/NoopSpan';
+export * from './trace/NoopTracer';
+export * from './trace/NoopTracerProvider';
 export * from './trace/Sampler';
-export * from './trace/span';
-export * from './trace/SpanOptions';
 export * from './trace/span_context';
 export * from './trace/span_kind';
+export * from './trace/span';
+export * from './trace/SpanOptions';
 export * from './trace/status';
 export * from './trace/TimedEvent';
-export * from './trace/tracer';
-export * from './trace/tracer_provider';
 export * from './trace/trace_flags';
 export * from './trace/trace_state';
-export * from './trace/NoopSpan';
-export * from './trace/NoopTracer';
-export * from './trace/NoopTracerProvider';
-export * from './metrics/NoopMeterProvider';
-export * from './metrics/NoopMeter';
+export * from './trace/tracer_provider';
+export * from './trace/tracer';
 
 import { TraceAPI } from './api/trace';
 /** Entrypoint for trace API */

packages/opentelemetry-api/src/metrics/BoundInstrument.ts

@@ -14,7 +14,6 @@
  * limitations under the License.
  */
 
-import { DistributedContext } from '../distributed_context/DistributedContext';
 import { SpanContext } from '../trace/span_context';
 
 /** An Instrument for Counter Metric. */
@@ -40,15 +39,9 @@ export interface BoundMeasure {
   /**
    * Records the given value to this measure.
    * @param value the measurement to record.
-   * @param distContext the distContext associated with the measurements.
    * @param spanContext the {@link SpanContext} that identifies the {@link Span}
    *     for which the measurements are associated with.
    */
   record(value: number): void;
-  record(value: number, distContext: DistributedContext): void;
-  record(
-    value: number,
-    distContext: DistributedContext,
-    spanContext: SpanContext
-  ): void;
+  record(value: number, spanContext: SpanContext): void;
 }

packages/opentelemetry-api/src/metrics/Metric.ts

@@ -14,7 +14,6 @@
  * limitations under the License.
  */
 
-import { DistributedContext } from '../distributed_context/DistributedContext';
 import { SpanContext } from '../trace/span_context';
 
 /**
@@ -123,18 +122,7 @@ export interface MetricUtils {
    */
   record(value: number, labelSet: LabelSet): void;
 
-  record(
-    value: number,
-    labelSet: LabelSet,
-    distContext: DistributedContext
-  ): void;
-
-  record(
-    value: number,
-    labelSet: LabelSet,
-    distContext: DistributedContext,
-    spanContext: SpanContext
-  ): void;
+  record(value: number, labelSet: LabelSet, spanContext: SpanContext): void;
 }
 
 /**

packages/opentelemetry-api/src/metrics/NoopMeter.ts

@@ -17,7 +17,6 @@
 import { Meter } from './Meter';
 import { MetricOptions, Metric, Labels, LabelSet, MetricUtils } from './Metric';
 import { BoundMeasure, BoundCounter, BoundGauge } from './BoundInstrument';
-import { DistributedContext } from '../distributed_context/DistributedContext';
 import { SpanContext } from '../trace/span_context';
 
 /**
@@ -119,18 +118,11 @@ export class NoopGaugeMetric extends NoopMetric<BoundGauge>
 
 export class NoopMeasureMetric extends NoopMetric<BoundMeasure>
   implements Pick<MetricUtils, 'record'> {
-  record(
-    value: number,
-    labelSet: LabelSet,
-    distContext?: DistributedContext,
-    spanContext?: SpanContext
-  ) {
-    if (typeof distContext === 'undefined') {
+  record(value: number, labelSet: LabelSet, spanContext?: SpanContext) {
+    if (typeof spanContext === 'undefined') {
       this.bind(labelSet).record(value);
-    } else if (typeof spanContext === 'undefined') {
-      this.bind(labelSet).record(value, distContext);
     } else {
-      this.bind(labelSet).record(value, distContext, spanContext);
+      this.bind(labelSet).record(value, spanContext);
     }
   }
 }
@@ -148,11 +140,7 @@ export class NoopBoundGauge implements BoundGauge {
 }
 
 export class NoopBoundMeasure implements BoundMeasure {
-  record(
-    value: number,
-    distContext?: DistributedContext,
-    spanContext?: SpanContext
-  ): void {
+  record(value: number, spanContext?: SpanContext): void {
     return;
   }
 }

packages/opentelemetry-api/test/noop-implementations/noop-tracer.test.ts

@@ -16,6 +16,7 @@
 
 import * as assert from 'assert';
 import { NoopTracer, NOOP_SPAN, SpanKind } from '../../src';
+import { Context } from '@opentelemetry/scope-base';
 
 describe('NoopTracer', () => {
   it('should not crash', () => {
@@ -38,8 +39,9 @@ describe('NoopTracer', () => {
     assert.deepStrictEqual(tracer.getCurrentSpan(), NOOP_SPAN);
     const httpTextFormat = tracer.getHttpTextFormat();
     assert.ok(httpTextFormat);
-    httpTextFormat.inject(spanContext, 'HttpTextFormat', {});
-    assert.deepStrictEqual(httpTextFormat.extract('HttpTextFormat', {}), null);
+
+    httpTextFormat.inject(Context.ROOT_CONTEXT, {});
+    assert.deepStrictEqual(httpTextFormat.extract(Context.ROOT_CONTEXT, {}), Context.ROOT_CONTEXT);
 
     const binaryFormat = tracer.getBinaryFormat();
     assert.ok(binaryFormat);

packages/opentelemetry-core/package.json

@@ -79,6 +79,7 @@
   },
   "dependencies": {
     "@opentelemetry/api": "^0.4.0",
+    "@opentelemetry/scope-base": "^0.4.0",
     "semver": "^6.3.0"
   }
 }