feat!(metrics): remove batch observer

examples/metrics/metrics/observer.js

@@ -27,66 +27,12 @@ meter.createObservableGauge('cpu_core_usage', {
   description: 'Example of a sync observable gauge with callback',
 }, async (observableResult) => { // this callback is called once per each interval
   await new Promise((resolve) => {
-    setTimeout(()=> {resolve()}, 50);
+    setTimeout(() => { resolve(); }, 50);
   });
   observableResult.observe(getRandomValue(), { core: '1' });
   observableResult.observe(getRandomValue(), { core: '2' });
 });
 
-// no callback as they will be updated in batch observer
-const tempMetric = meter.createObservableGauge('cpu_temp_per_app', {
-  description: 'Example of sync observable gauge used with async batch observer',
-});
-
-// no callback as they will be updated in batch observer
-const cpuUsageMetric = meter.createObservableGauge('cpu_usage_per_app', {
-  description: 'Example of sync observable gauge used with async batch observer',
-});
-
-meter.createBatchObserver((batchObserverResult) => {
-    Promise.all([
-      someAsyncMetrics(),
-      // simulate waiting
-      new Promise((resolve, reject) => {
-        setTimeout(resolve, 300);
-      }),
-    ]).then(([apps, waiting]) => {
-      apps.forEach(app => {
-        batchObserverResult.observe({ app: app.name, core: '1' }, [
-          tempMetric.observation(app.core1.temp),
-          cpuUsageMetric.observation(app.core1.usage),
-        ]);
-        batchObserverResult.observe({ app: app.name, core: '2' }, [
-          tempMetric.observation(app.core2.temp),
-          cpuUsageMetric.observation(app.core2.usage),
-        ]);
-      });
-    });
-  }, {
-    maxTimeoutUpdateMS: 500,
-  },
-);
-
-function someAsyncMetrics() {
-  return new Promise((resolve) => {
-    setTimeout(() => {
-      const stats = [
-        {
-          name: 'app1',
-          core1: { usage: getRandomValue(), temp: getRandomValue() * 100 },
-          core2: { usage: getRandomValue(), temp: getRandomValue() * 100 },
-        },
-        {
-          name: 'app2',
-          core1: { usage: getRandomValue(), temp: getRandomValue() * 100 },
-          core2: { usage: getRandomValue(), temp: getRandomValue() * 100 },
-        },
-      ];
-      resolve(stats);
-    }, 200);
-  });
-}
-
 function getRandomValue() {
   return Math.random();
 }

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

@@ -14,7 +14,6 @@
  * limitations under the License.
  */
 
-import { BatchObserverResult } from './types/BatchObserverResult';
 import { Meter } from './types/Meter';
 import {
   MetricOptions,
@@ -111,17 +110,6 @@ export class NoopMeter implements Meter {
   ): ObservableUpDownCounter {
     return NOOP_OBSERVABLE_UP_DOWN_COUNTER_METRIC;
   }
-
-  /**
-   * Returns constant noop batch observer.
-   * @param name the name of the metric.
-   * @param callback the batch observer callback
-   */
-  createBatchObserver(
-    _callback: (batchObserverResult: BatchObserverResult) => void
-  ): NoopBatchObserver {
-    return NOOP_BATCH_OBSERVER;
-  }
 }
 
 export class NoopMetric<T> implements UnboundMetric<T> {
@@ -185,8 +173,6 @@ export class NoopObservableBaseMetric
   }
 }
 
-export class NoopBatchObserver {}
-
 export class NoopBoundCounter implements BoundCounter {
   add(_value: number): void {
     return;
@@ -224,5 +210,3 @@ export const NOOP_OBSERVABLE_UP_DOWN_COUNTER_METRIC = new NoopObservableBaseMetr
 export const NOOP_OBSERVABLE_COUNTER_METRIC = new NoopObservableBaseMetric(
   NOOP_BOUND_OBSERVABLE_BASE
 );
-
-export const NOOP_BATCH_OBSERVER = new NoopBatchObserver();

experimental/packages/opentelemetry-api-metrics/src/index.ts

@@ -16,7 +16,6 @@
 
 export * from './NoopMeter';
 export * from './NoopMeterProvider';
-export * from './types/BatchObserverResult';
 export * from './types/BoundInstrument';
 export * from './types/Meter';
 export * from './types/MeterProvider';

experimental/packages/opentelemetry-api-metrics/src/types/Meter.ts

@@ -14,13 +14,11 @@
  * limitations under the License.
  */
 
-import { BatchObserverResult } from './BatchObserverResult';
 import {
   MetricOptions,
   Counter,
   Histogram,
   ObservableGauge,
-  BatchObserverOptions,
   UpDownCounter,
   ObservableCounter,
   ObservableUpDownCounter,
@@ -105,15 +103,4 @@ export interface Meter {
     options?: MetricOptions,
     callback?: (observableResult: ObservableResult) => void
   ): ObservableUpDownCounter;
-
-  /**
-   * Creates a new `BatchObserver`, can be used to update many metrics
-   * at the same time and when operations needs to be async
-   * @param callback the batch observer callback
-   * @param [options] the batch observer options.
-   */
-  createBatchObserver(
-    callback: (batchObserverResult: BatchObserverResult) => void,
-    options?: BatchObserverOptions
-  ): void;
 }

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

@@ -68,13 +68,6 @@ export interface MetricOptions {
   aggregationTemporality?: AggregationTemporality;
 }
 
-export interface BatchObserverOptions {
-  /**
-   * Indicates how long the batch metric should wait to update before cancel
-   */
-  maxTimeoutUpdateMS?: number;
-}
-
 /** The Type of value. It describes how the data is reported. */
 export enum ValueType {
   INT,

experimental/packages/opentelemetry-sdk-metrics-base/README.md

@@ -191,60 +191,6 @@ function getRandomValue() {
 }
 ```
 
-### Batch Observer
-
-Choose this kind of metric when you need to update multiple observables with the results of a single async calculation.
-
-```js
-const { MeterProvider } = require('@opentelemetry/sdk-metrics-base');
-const { PrometheusExporter } = require('@opentelemetry/exporter-prometheus');
-
-const exporter = new PrometheusExporter(
-  {
-    startServer: true,
-  },
-  () => {
-    console.log('prometheus scrape endpoint: http://localhost:9464/metrics');
-  },
-);
-
-const meter = new MeterProvider({
-  exporter,
-  interval: 3000,
-}).getMeter('example-observer');
-
-const cpuUsageMetric = meter.createObservableGauge('cpu_usage_per_app', {
-  description: 'CPU',
-});
-
-const MemUsageMetric = meter.createObservableGauge('mem_usage_per_app', {
-  description: 'Memory',
-});
-
-meter.createBatchObserver((batchObserverResult) => {
-  getSomeAsyncMetrics().then(metrics => {
-    batchObserverResult.observe({ app: 'myApp' }, [
-      cpuUsageMetric.observation(metrics.value1),
-      MemUsageMetric.observation(metrics.value2)
-    ]);
-  });
-});
-
-function getSomeAsyncMetrics() {
-  return new Promise((resolve, reject) => {
-    setTimeout(() => {
-      resolve({
-        value1: Math.random(),
-        value2: Math.random(),
-      });
-    }, 100)
-  });
-}
-
-```
-
-See [examples/prometheus](https://github.com/open-telemetry/opentelemetry-js/tree/main/examples/prometheus) for a short example.
-
 ### Histogram
 
 `Histogram` is a non-additive synchronous instrument useful for recording any non-additive number, positive or negative.