From aaa9b453c7e2bc71ea9d0f545f3569ffef366fe8 Mon Sep 17 00:00:00 2001
From: legendecas <legendecas@gmail.com>
Date: Thu, 20 Jan 2022 11:45:59 +0800
Subject: [PATCH 1/3] feat(sdk-metrics-base): document and export basic APIs

---
 .../src/InstrumentDescriptor.ts               | 13 +++++-
 .../src/Instruments.ts                        | 34 +++++++++------
 .../src/Meter.ts                              | 41 ++++++++++++++-----
 .../src/MeterProvider.ts                      | 25 ++++++++---
 .../src/ObservableResult.ts                   |  9 ++++
 .../src/export/AggregationTemporality.ts      |  2 +-
 .../src/export/MetricData.ts                  | 32 +++++++++++++++
 .../src/index.ts                              | 11 ++++-
 .../src/view/Aggregation.ts                   | 37 +++++++++++++----
 .../src/view/InstrumentSelector.ts            |  2 +-
 .../test/util.ts                              |  4 +-
 .../test/view/Aggregation.test.ts             |  3 +-
 .../test/view/ViewRegistry.test.ts            |  2 +-
 13 files changed, 171 insertions(+), 44 deletions(-)

diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/InstrumentDescriptor.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/InstrumentDescriptor.ts
index 8aa57c9f68d..ecb7543a5a5 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/InstrumentDescriptor.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/InstrumentDescriptor.ts
@@ -15,9 +15,20 @@
  */
 
 import { MetricOptions, ValueType } from '@opentelemetry/api-metrics-wip';
-import { InstrumentType } from './Instruments';
 import { View } from './view/View';
 
+/**
+ * Supported types of metric instruments.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#instrument
+ */
+ export enum InstrumentType {
+  COUNTER = 'COUNTER',
+  HISTOGRAM = 'HISTOGRAM',
+  UP_DOWN_COUNTER = 'UP_DOWN_COUNTER',
+  OBSERVABLE_COUNTER = 'OBSERVABLE_COUNTER',
+  OBSERVABLE_GAUGE = 'OBSERVABLE_GAUGE',
+  OBSERVABLE_UP_DOWN_COUNTER = 'OBSERVABLE_UP_DOWN_COUNTER',
+}
 
 export interface InstrumentDescriptor {
   readonly name: string;
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/Instruments.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/Instruments.ts
index decf7047945..309bea68059 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/Instruments.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/Instruments.ts
@@ -19,17 +19,6 @@ import * as metrics from '@opentelemetry/api-metrics-wip';
 import { InstrumentDescriptor } from './InstrumentDescriptor';
 import { WritableMetricStorage } from './state/WritableMetricStorage';
 
-// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#instrument
-
-export enum InstrumentType {
-  COUNTER = 'COUNTER',
-  HISTOGRAM = 'HISTOGRAM',
-  UP_DOWN_COUNTER = 'UP_DOWN_COUNTER',
-  OBSERVABLE_COUNTER = 'OBSERVABLE_COUNTER',
-  OBSERVABLE_GAUGE = 'OBSERVABLE_GAUGE',
-  OBSERVABLE_UP_DOWN_COUNTER = 'OBSERVABLE_UP_DOWN_COUNTER',
-}
-
 export class SyncInstrument {
   constructor(private _writableMetricStorage: WritableMetricStorage, private _descriptor: InstrumentDescriptor) { }
 
@@ -42,13 +31,27 @@ export class SyncInstrument {
   }
 }
 
-export class UpDownCounter extends SyncInstrument implements metrics.Counter {
+/**
+ * The class implements {@link metrics.UpDownCounter} interface.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#updowncounter
+ */
+export class UpDownCounter extends SyncInstrument implements metrics.UpDownCounter {
+  /**
+   * Increment value of counter by the input. Inputs may be negative.
+   */
   add(value: number, attributes?: metrics.Attributes, ctx?: api.Context): void {
     this.aggregate(value, attributes, ctx);
   }
 }
 
+/**
+ * The class implements {@link metrics.Counter} interface.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#counter
+ */
 export class Counter extends SyncInstrument implements metrics.Counter {
+  /**
+   * Increment value of counter by the input. Inputs may not be negative.
+   */
   add(value: number, attributes?: metrics.Attributes, ctx?: api.Context): void {
     if (value < 0) {
       api.diag.warn(`negative value provided to counter ${this.getName()}: ${value}`);
@@ -59,7 +62,14 @@ export class Counter extends SyncInstrument implements metrics.Counter {
   }
 }
 
+/**
+ * The class implements {@link metrics.Histogram} interface.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#histogram
+ */
 export class Histogram extends SyncInstrument implements metrics.Histogram {
+  /**
+   * Records a measurement. Value of the measurement must not be negative.
+   */
   record(value: number, attributes?: metrics.Attributes, ctx?: api.Context): void {
     this.aggregate(value, attributes, ctx);
   }
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/Meter.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/Meter.ts
index 7808db28e26..de09deb3910 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/Meter.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/Meter.ts
@@ -16,8 +16,8 @@
 
 import * as metrics from '@opentelemetry/api-metrics-wip';
 import { InstrumentationLibrary } from '@opentelemetry/core';
-import { createInstrumentDescriptor, InstrumentDescriptor } from './InstrumentDescriptor';
-import { Counter, Histogram, InstrumentType, UpDownCounter } from './Instruments';
+import { createInstrumentDescriptor, InstrumentDescriptor, InstrumentType } from './InstrumentDescriptor';
+import { Counter, Histogram, UpDownCounter } from './Instruments';
 import { MeterProviderSharedState } from './state/MeterProviderSharedState';
 import { MultiMetricStorage } from './state/MultiWritableMetricStorage';
 import { SyncMetricStorage } from './state/SyncMetricStorage';
@@ -28,40 +28,47 @@ import { MetricCollectorHandle } from './state/MetricCollector';
 import { HrTime } from '@opentelemetry/api';
 import { AsyncMetricStorage } from './state/AsyncMetricStorage';
 
-// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#meter
-
+/**
+ * This class implements the {@link metrics.Meter} interface.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#meter
+ */
 export class Meter implements metrics.Meter {
   private _metricStorageRegistry = new Map<string, MetricStorage>();
 
-  // instrumentation library required by spec to be on meter
-  // spec requires provider config changes to apply to previously created meters, achieved by holding a reference to the provider
   constructor(private _meterProviderSharedState: MeterProviderSharedState, private _instrumentationLibrary: InstrumentationLibrary) {
     this._meterProviderSharedState.meters.push(this);
   }
 
-  /** this exists just to prevent ts errors from unused variables and may be removed */
-  getInstrumentationLibrary(): InstrumentationLibrary {
-    return this._instrumentationLibrary;
-  }
-
+  /**
+   * Create a {@link metrics.Histogram} instrument.
+   */
   createHistogram(name: string, options?: metrics.HistogramOptions): metrics.Histogram {
     const descriptor = createInstrumentDescriptor(name, InstrumentType.HISTOGRAM, options);
     const storage = this._registerMetricStorage(descriptor);
     return new Histogram(storage, descriptor);
   }
 
+  /**
+   * Create a {@link metrics.Counter} instrument.
+   */
   createCounter(name: string, options?: metrics.CounterOptions): metrics.Counter {
     const descriptor = createInstrumentDescriptor(name, InstrumentType.COUNTER, options);
     const storage = this._registerMetricStorage(descriptor);
     return new Counter(storage, descriptor);
   }
 
+  /**
+   * Create a {@link metrics.UpDownCounter} instrument.
+   */
   createUpDownCounter(name: string, options?: metrics.UpDownCounterOptions): metrics.UpDownCounter {
     const descriptor = createInstrumentDescriptor(name, InstrumentType.UP_DOWN_COUNTER, options);
     const storage = this._registerMetricStorage(descriptor);
     return new UpDownCounter(storage, descriptor);
   }
 
+  /**
+   * Create a ObservableGauge instrument.
+   */
   createObservableGauge(
     name: string,
     callback: metrics.ObservableCallback,
@@ -71,6 +78,9 @@ export class Meter implements metrics.Meter {
     this._registerAsyncMetricStorage(descriptor, callback);
   }
 
+  /**
+   * Create a ObservableCounter instrument.
+   */
   createObservableCounter(
     name: string,
     callback: metrics.ObservableCallback,
@@ -80,6 +90,9 @@ export class Meter implements metrics.Meter {
     this._registerAsyncMetricStorage(descriptor, callback);
   }
 
+  /**
+   * Create a ObservableUpDownCounter instrument.
+   */
   createObservableUpDownCounter(
     name: string,
     callback: metrics.ObservableCallback,
@@ -112,6 +125,12 @@ export class Meter implements metrics.Meter {
     });
   }
 
+  /**
+   * @internal
+   * @param collector opaque handle of {@link MetricCollector} which initiated the collection.
+   * @param collectionTime the HrTime at which the collection was initiated.
+   * @returns the list of {@link MetricData} collected.
+   */
   async collect(collector: MetricCollectorHandle, collectionTime: HrTime): Promise<MetricData[]> {
     const result = await Promise.all(Array.from(this._metricStorageRegistry.values()).map(metricStorage => {
       return metricStorage.collect(
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/MeterProvider.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/MeterProvider.ts
index d7b30e30814..a72deacf3e8 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/MeterProvider.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/MeterProvider.ts
@@ -25,13 +25,19 @@ import { MeterSelector } from './view/MeterSelector';
 import { View } from './view/View';
 import { MetricCollector } from './state/MetricCollector';
 
-// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#meterprovider
-
-export type MeterProviderOptions = {
+/**
+ * MeterProviderOptions provides an interface for configuring a MeterProvider.
+ */
+export interface MeterProviderOptions {
+  /** Resource associated with metric telemetry  */
   resource?: Resource;
-};
+}
 
-export class MeterProvider {
+/**
+ * This class implements the {@link metrics.MeterProvider} interface.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#meterprovider
+ */
+export class MeterProvider implements metrics.MeterProvider {
   private _sharedState: MeterProviderSharedState;
   private _shutdown = false;
 
@@ -39,6 +45,9 @@ export class MeterProvider {
     this._sharedState = new MeterProviderSharedState(options?.resource ?? Resource.empty());
   }
 
+  /**
+   * Get a meter with the configuration of the MeterProvider.
+   */
   getMeter(name: string, version = '', options: metrics.MeterOptions = {}): metrics.Meter {
     // https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#meter-creation
     if (this._shutdown) {
@@ -49,6 +58,12 @@ export class MeterProvider {
     return new Meter(this._sharedState, { name, version, schemaUrl: options.schemaUrl });
   }
 
+  /**
+   * Register a {@link MetricReader} to the meter provider. After the
+   * registration, the MetricReader can start metrics collection.
+   *
+   * @param metricReader the metric reader to be registered.
+   */
   addMetricReader(metricReader: MetricReader) {
     const collector = new MetricCollector(this._sharedState, metricReader);
     metricReader.setMetricProducer(collector);
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/ObservableResult.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/ObservableResult.ts
index c10bf7514ed..7ca9f9aea1d 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/ObservableResult.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/ObservableResult.ts
@@ -17,9 +17,18 @@
 import * as metrics from '@opentelemetry/api-metrics-wip';
 import { AttributeHashMap } from './state/HashMap';
 
+/**
+ * The class implements {@link metrics.observableResult} interface.
+ */
 export class ObservableResult implements metrics.ObservableResult {
+  /**
+   * @internal
+   */
   buffer = new AttributeHashMap<number>();
 
+  /**
+   * Observe a measurement of the value associated with the given attributes.
+   */
   observe(value: number, attributes: metrics.Attributes = {}): void {
     this.buffer.set(attributes, value);
   }
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/export/AggregationTemporality.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/export/AggregationTemporality.ts
index 744d936d012..6ecb2bb9734 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/export/AggregationTemporality.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/export/AggregationTemporality.ts
@@ -17,7 +17,7 @@
 /**
  * AggregationTemporality indicates the way additive quantities are expressed.
  *
- * https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/datamodel.md#temporality
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/datamodel.md#temporality
  */
 export enum AggregationTemporality {
   DELTA,
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/export/MetricData.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/export/MetricData.ts
index d989baa0b7d..e8d9c71a5ef 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/export/MetricData.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/export/MetricData.ts
@@ -21,31 +21,63 @@ import { Resource } from '@opentelemetry/resources';
 import { InstrumentDescriptor } from '../InstrumentDescriptor';
 import { Histogram } from '../aggregator/types';
 
+/**
+ * Basic metric data fields.
+ */
 export interface BaseMetricData {
+  /**
+   * Resource associated with metric telemetry
+   */
   readonly resource: Resource;
+  /**
+   * InstrumentationLibrary which created the metric instrument.
+   */
   readonly instrumentationLibrary: InstrumentationLibrary;
+  /**
+   * InstrumentDescriptor which describes the metric instrument.
+   */
   readonly instrumentDescriptor: InstrumentDescriptor;
+  /**
+   * PointDataType of the metric instrument.
+   */
   readonly pointDataType: PointDataType,
 }
 
+/**
+ * Represents a metric data aggregated by either a LastValueAggregation or
+ * SumAggregation.
+ */
 export interface SingularMetricData extends BaseMetricData {
   readonly pointDataType: PointDataType.SINGULAR,
   readonly pointData: PointData<number>[],
 }
 
+/**
+ * Represents a metric data aggregated by a HistogramAggregation.
+ */
 export interface HistogramMetricData extends BaseMetricData {
   readonly pointDataType: PointDataType.HISTOGRAM,
   readonly pointData: PointData<Histogram>[],
 }
 
+/**
+ * Represents an aggregated metric data.
+ */
 export type MetricData = SingularMetricData | HistogramMetricData;
 
+/**
+ * The aggregated point data type
+ */
 export enum PointDataType {
   SINGULAR,
   HISTOGRAM,
   EXPONENTIAL_HISTOGRAM,
 }
 
+/**
+ * Represents an aggregated point data with start time, end time and their
+ * associated attributes and points.
+ */
 export interface PointData<T> {
   /**
    * The start epoch timestamp of the PointData, usually the time when
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/index.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/index.ts
index 35622792a2f..ba9b60de026 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/index.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/index.ts
@@ -14,6 +14,15 @@
  * limitations under the License.
  */
 
-export { MeterProvider, MeterProviderOptions } from './MeterProvider';
+export * from './export/AggregationTemporality';
+export * from './export/MetricData';
 export * from './export/MetricExporter';
+export * from './export/MetricProducer';
 export * from './export/MetricReader';
+export * from './export/PeriodicExportingMetricReader';
+export { InstrumentDescriptor, InstrumentType } from './InstrumentDescriptor';
+export * from './Instruments';
+export * from './Meter';
+export * from './MeterProvider';
+export * from './ObservableResult';
+export { TimeoutError } from './utils';
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/view/Aggregation.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/view/Aggregation.ts
index b2b7b6a32ce..923126b146a 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/view/Aggregation.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/view/Aggregation.ts
@@ -17,16 +17,15 @@
 import * as api from '@opentelemetry/api';
 import { Aggregator, SumAggregator, DropAggregator, LastValueAggregator, HistogramAggregator } from '../aggregator';
 import { Accumulation } from '../aggregator/types';
-import { InstrumentDescriptor } from '../InstrumentDescriptor';
-import { InstrumentType } from '../Instruments';
+import { InstrumentDescriptor, InstrumentType } from '../InstrumentDescriptor';
 import { Maybe } from '../utils';
 
-// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#aggregation
-
 /**
- * Configures how measurements are combined into metrics for {@link View}s.
+ * Configures how measurements are combined into metrics for views.
  *
  * Aggregation provides a set of built-in aggregations via static methods.
+ *
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#aggregation
  */
 export abstract class Aggregation {
   abstract createAggregator(instrument: InstrumentDescriptor): Aggregator<Maybe<Accumulation>>;
@@ -52,6 +51,10 @@ export abstract class Aggregation {
   }
 }
 
+/**
+ * The default drop aggregation.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#drop-aggregation
+ */
 export class DropAggregation extends Aggregation {
   private static DEFAULT_INSTANCE = new DropAggregator();
   createAggregator(_instrument: InstrumentDescriptor) {
@@ -59,6 +62,10 @@ export class DropAggregation extends Aggregation {
   }
 }
 
+/**
+ * The default sum aggregation.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#sum-aggregation
+ */
 export class SumAggregation extends Aggregation {
   private static DEFAULT_INSTANCE = new SumAggregator();
   createAggregator(_instrument: InstrumentDescriptor) {
@@ -66,6 +73,10 @@ export class SumAggregation extends Aggregation {
   }
 }
 
+/**
+ * The default last value aggregation.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#last-value-aggregation
+ */
 export class LastValueAggregation extends Aggregation {
   private static DEFAULT_INSTANCE = new LastValueAggregator();
   createAggregator(_instrument: InstrumentDescriptor) {
@@ -73,15 +84,25 @@ export class LastValueAggregation extends Aggregation {
   }
 }
 
+/**
+ * The default histogram aggregation.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#histogram-aggregation
+ */
 export class HistogramAggregation extends Aggregation {
-  // https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#histogram-aggregation
   private static DEFAULT_INSTANCE = new HistogramAggregator([0, 5, 10, 25, 50, 75, 100, 250, 500, 1000]);
   createAggregator(_instrument: InstrumentDescriptor) {
     return HistogramAggregation.DEFAULT_INSTANCE;
   }
 }
 
+/**
+ * The explicit bucket histogram aggregation.
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#explicit-bucket-histogram-aggregation
+ */
 export class ExplicitBucketHistogramAggregation extends Aggregation {
+  /**
+   * @param _boundaries the bucket boundaries of the histogram aggregation
+   */
   constructor(private _boundaries: number[]) {
     super();
   }
@@ -91,7 +112,9 @@ export class ExplicitBucketHistogramAggregation extends Aggregation {
   }
 }
 
-// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#default-aggregation
+/**
+ * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#default-aggregation
+ */
 export class DefaultAggregation extends Aggregation {
   private _resolve(instrument: InstrumentDescriptor): Aggregation {
     // cast to unknown to disable complaints on the (unreachable) fallback.
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/view/InstrumentSelector.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/view/InstrumentSelector.ts
index c7dc6fa28e5..e7bec3a44a2 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/view/InstrumentSelector.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/view/InstrumentSelector.ts
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { InstrumentType } from '../Instruments';
+import { InstrumentType } from '../InstrumentDescriptor';
 import { PatternPredicate, Predicate } from './Predicate';
 
 export interface InstrumentSelectorCriteria {
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/test/util.ts b/experimental/packages/opentelemetry-sdk-metrics-base/test/util.ts
index 301a2a9e447..917277e4363 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/test/util.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/test/util.ts
@@ -18,8 +18,8 @@ import { Attributes, ValueType } from '@opentelemetry/api-metrics';
 import { InstrumentationLibrary } from '@opentelemetry/core';
 import { Resource } from '@opentelemetry/resources';
 import * as assert from 'assert';
-import { InstrumentDescriptor } from '../src/InstrumentDescriptor';
-import { Histogram, InstrumentType } from '../src/Instruments';
+import { InstrumentDescriptor, InstrumentType } from '../src/InstrumentDescriptor';
+import { Histogram } from '../src/Instruments';
 import { MetricData, PointData, PointDataType } from '../src/export/MetricData';
 import { Measurement } from '../src/Measurement';
 import { isNotNullish } from '../src/utils';
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/test/view/Aggregation.test.ts b/experimental/packages/opentelemetry-sdk-metrics-base/test/view/Aggregation.test.ts
index 717c74a1ad0..6ce420a5114 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/test/view/Aggregation.test.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/test/view/Aggregation.test.ts
@@ -22,8 +22,7 @@ import {
   LastValueAggregator,
   SumAggregator,
 } from '../../src/aggregator';
-import { InstrumentDescriptor } from '../../src/InstrumentDescriptor';
-import { InstrumentType } from '../../src/Instruments';
+import { InstrumentDescriptor, InstrumentType } from '../../src/InstrumentDescriptor';
 import {
   Aggregation,
   DefaultAggregation,
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/test/view/ViewRegistry.test.ts b/experimental/packages/opentelemetry-sdk-metrics-base/test/view/ViewRegistry.test.ts
index dd1321a400c..db5e0cf3808 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/test/view/ViewRegistry.test.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/test/view/ViewRegistry.test.ts
@@ -15,7 +15,7 @@
  */
 
 import * as assert from 'assert';
-import { InstrumentType } from '../../src/Instruments';
+import { InstrumentType } from '../../src/InstrumentDescriptor';
 import { ViewRegistry } from '../../src/view/ViewRegistry';
 import { View } from '../../src/view/View';
 import { InstrumentSelector } from '../../src/view/InstrumentSelector';

From 8d77102927d0cf173dd051312c7eabb0f758f90a Mon Sep 17 00:00:00 2001
From: legendecas <legendecas@gmail.com>
Date: Mon, 24 Jan 2022 11:01:50 +0800
Subject: [PATCH 2/3] fixup!

---
 .../opentelemetry-sdk-metrics-base/src/Instruments.ts    | 3 ---
 .../packages/opentelemetry-sdk-metrics-base/src/Meter.ts | 1 -
 .../opentelemetry-sdk-metrics-base/src/MeterProvider.ts  | 1 -
 .../exemplar/AlignedHistogramBucketExemplarReservoir.ts  | 3 +--
 .../src/export/AggregationTemporality.ts                 | 2 --
 .../src/export/MetricData.ts                             | 4 ++--
 .../src/view/Aggregation.ts                              | 9 +--------
 7 files changed, 4 insertions(+), 19 deletions(-)

diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/Instruments.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/Instruments.ts
index 309bea68059..60dbc9e364a 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/Instruments.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/Instruments.ts
@@ -33,7 +33,6 @@ export class SyncInstrument {
 
 /**
  * The class implements {@link metrics.UpDownCounter} interface.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#updowncounter
  */
 export class UpDownCounter extends SyncInstrument implements metrics.UpDownCounter {
   /**
@@ -46,7 +45,6 @@ export class UpDownCounter extends SyncInstrument implements metrics.UpDownCount
 
 /**
  * The class implements {@link metrics.Counter} interface.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#counter
  */
 export class Counter extends SyncInstrument implements metrics.Counter {
   /**
@@ -64,7 +62,6 @@ export class Counter extends SyncInstrument implements metrics.Counter {
 
 /**
  * The class implements {@link metrics.Histogram} interface.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#histogram
  */
 export class Histogram extends SyncInstrument implements metrics.Histogram {
   /**
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/Meter.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/Meter.ts
index de09deb3910..cc4c54545c3 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/Meter.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/Meter.ts
@@ -30,7 +30,6 @@ import { AsyncMetricStorage } from './state/AsyncMetricStorage';
 
 /**
  * This class implements the {@link metrics.Meter} interface.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#meter
  */
 export class Meter implements metrics.Meter {
   private _metricStorageRegistry = new Map<string, MetricStorage>();
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/MeterProvider.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/MeterProvider.ts
index a72deacf3e8..d9e6d951a1e 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/MeterProvider.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/MeterProvider.ts
@@ -35,7 +35,6 @@ export interface MeterProviderOptions {
 
 /**
  * This class implements the {@link metrics.MeterProvider} interface.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#meterprovider
  */
 export class MeterProvider implements metrics.MeterProvider {
   private _sharedState: MeterProviderSharedState;
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/exemplar/AlignedHistogramBucketExemplarReservoir.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/exemplar/AlignedHistogramBucketExemplarReservoir.ts
index 9c09abf9cfe..f69487ec066 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/exemplar/AlignedHistogramBucketExemplarReservoir.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/exemplar/AlignedHistogramBucketExemplarReservoir.ts
@@ -22,9 +22,8 @@ import { FixedSizeExemplarReservoirBase } from './ExemplarReservoir';
 
 /**
  * AlignedHistogramBucketExemplarReservoir takes the same boundaries
- * configuration of a Histogram. This alogorithm keeps the last seen measurement
+ * configuration of a Histogram. This algorithm keeps the last seen measurement
  * that falls within a histogram bucket.
- * https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#exemplar-defaults
  */
 export class AlignedHistogramBucketExemplarReservoir extends FixedSizeExemplarReservoirBase {
   private _boundaries: number[];
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/export/AggregationTemporality.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/export/AggregationTemporality.ts
index 6ecb2bb9734..6cc6d1231bf 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/export/AggregationTemporality.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/export/AggregationTemporality.ts
@@ -16,8 +16,6 @@
 
 /**
  * AggregationTemporality indicates the way additive quantities are expressed.
- *
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/datamodel.md#temporality
  */
 export enum AggregationTemporality {
   DELTA,
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/export/MetricData.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/export/MetricData.ts
index e8d9c71a5ef..736c83034ac 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/export/MetricData.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/export/MetricData.ts
@@ -26,7 +26,7 @@ import { Histogram } from '../aggregator/types';
  */
 export interface BaseMetricData {
   /**
-   * Resource associated with metric telemetry
+   * Resource associated with metric telemetry.
    */
   readonly resource: Resource;
   /**
@@ -66,7 +66,7 @@ export interface HistogramMetricData extends BaseMetricData {
 export type MetricData = SingularMetricData | HistogramMetricData;
 
 /**
- * The aggregated point data type
+ * The aggregated point data type.
  */
 export enum PointDataType {
   SINGULAR,
diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/view/Aggregation.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/view/Aggregation.ts
index 923126b146a..601461238a3 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/view/Aggregation.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/view/Aggregation.ts
@@ -24,8 +24,6 @@ import { Maybe } from '../utils';
  * Configures how measurements are combined into metrics for views.
  *
  * Aggregation provides a set of built-in aggregations via static methods.
- *
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#aggregation
  */
 export abstract class Aggregation {
   abstract createAggregator(instrument: InstrumentDescriptor): Aggregator<Maybe<Accumulation>>;
@@ -53,7 +51,6 @@ export abstract class Aggregation {
 
 /**
  * The default drop aggregation.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#drop-aggregation
  */
 export class DropAggregation extends Aggregation {
   private static DEFAULT_INSTANCE = new DropAggregator();
@@ -64,7 +61,6 @@ export class DropAggregation extends Aggregation {
 
 /**
  * The default sum aggregation.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#sum-aggregation
  */
 export class SumAggregation extends Aggregation {
   private static DEFAULT_INSTANCE = new SumAggregator();
@@ -75,7 +71,6 @@ export class SumAggregation extends Aggregation {
 
 /**
  * The default last value aggregation.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#last-value-aggregation
  */
 export class LastValueAggregation extends Aggregation {
   private static DEFAULT_INSTANCE = new LastValueAggregator();
@@ -86,7 +81,6 @@ export class LastValueAggregation extends Aggregation {
 
 /**
  * The default histogram aggregation.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#histogram-aggregation
  */
 export class HistogramAggregation extends Aggregation {
   private static DEFAULT_INSTANCE = new HistogramAggregator([0, 5, 10, 25, 50, 75, 100, 250, 500, 1000]);
@@ -97,7 +91,6 @@ export class HistogramAggregation extends Aggregation {
 
 /**
  * The explicit bucket histogram aggregation.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#explicit-bucket-histogram-aggregation
  */
 export class ExplicitBucketHistogramAggregation extends Aggregation {
   /**
@@ -113,7 +106,7 @@ export class ExplicitBucketHistogramAggregation extends Aggregation {
 }
 
 /**
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#default-aggregation
+ * The default aggregation.
  */
 export class DefaultAggregation extends Aggregation {
   private _resolve(instrument: InstrumentDescriptor): Aggregation {

From b7774be08de7a72e307969b2fd37129356769289 Mon Sep 17 00:00:00 2001
From: legendecas <legendecas@gmail.com>
Date: Mon, 24 Jan 2022 11:11:40 +0800
Subject: [PATCH 3/3] fixup!

---
 .../opentelemetry-sdk-metrics-base/src/InstrumentDescriptor.ts   | 1 -
 1 file changed, 1 deletion(-)

diff --git a/experimental/packages/opentelemetry-sdk-metrics-base/src/InstrumentDescriptor.ts b/experimental/packages/opentelemetry-sdk-metrics-base/src/InstrumentDescriptor.ts
index ecb7543a5a5..92ba0f70174 100644
--- a/experimental/packages/opentelemetry-sdk-metrics-base/src/InstrumentDescriptor.ts
+++ b/experimental/packages/opentelemetry-sdk-metrics-base/src/InstrumentDescriptor.ts
@@ -19,7 +19,6 @@ import { View } from './view/View';
 
 /**
  * Supported types of metric instruments.
- * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/api.md#instrument
  */
  export enum InstrumentType {
   COUNTER = 'COUNTER',