fix(sdk-metrics): ignore in accumulation instead

Author: pichlermarc

packages/sdk-metrics/src/Instruments.ts

@@ -54,12 +54,6 @@ export class SyncInstrument {
       );
       return;
     }
-    if (Number.isNaN(value)) {
-      diag.warn(
-        `NaN provided to metric ${this._descriptor.name}, ignoring to preserve the integrity of the metrics stream`
-      );
-      return;
-    }
     if (
       this._descriptor.valueType === ValueType.INT &&
       !Number.isInteger(value)

packages/sdk-metrics/src/aggregator/ExponentialHistogram.ts

@@ -193,6 +193,12 @@ export class ExponentialHistogramAccumulation implements Accumulation {
    * @param increment
    */
   updateByIncrement(value: number, increment: number) {
+    // NaN does not fall into any bucket, is not zero and should not be counted,
+    // NaN is never greater than max nor less than min, therefore return as there's nothing for us to do.
+    if (Number.isNaN(value)) {
+      return;
+    }
+
     if (value > this._max) {
       this._max = value;
     }

packages/sdk-metrics/src/aggregator/Histogram.ts

@@ -72,6 +72,12 @@ export class HistogramAccumulation implements Accumulation {
   ) {}
 
   record(value: number): void {
+    // NaN does not fall into any bucket, is not zero and should not be counted,
+    // NaN is never greater than max nor less than min, therefore return as there's nothing for us to do.
+    if (Number.isNaN(value)) {
+      return;
+    }
+
     this._current.count += 1;
     this._current.sum += value;
 

packages/sdk-metrics/test/Instruments.test.ts

@@ -135,7 +135,6 @@ describe('Instruments', () => {
       counter.add(1.2, { foo: 'bar' });
       // non-number values should be ignored.
       counter.add('1' as any);
-      counter.add(NaN);
 
       await validateExport(cumulativeReader, {
         dataPointType: DataPointType.SUM,
@@ -248,7 +247,6 @@ describe('Instruments', () => {
       upDownCounter.add(1.1, { foo: 'bar' });
       // non-number values should be ignored.
       upDownCounter.add('1' as any);
-      upDownCounter.add(NaN);
 
       await validateExport(deltaReader, {
         dataPointType: DataPointType.SUM,

packages/sdk-metrics/test/aggregator/ExponentialHistogram.test.ts

@@ -215,6 +215,20 @@ describe('ExponentialHistogramAccumulation', () => {
         }
       });
     });
+
+    it('ignores NaN', () => {
+      const accumulation = new ExponentialHistogramAccumulation([0, 0], 1);
+
+      accumulation.record(NaN);
+
+      assert.strictEqual(accumulation.scale, 0);
+      assert.strictEqual(accumulation.max, -Infinity);
+      assert.strictEqual(accumulation.min, Infinity);
+      assert.strictEqual(accumulation.sum, 0);
+      assert.strictEqual(accumulation.count, 0);
+      assert.deepStrictEqual(getCounts(accumulation.positive), []);
+      assert.deepStrictEqual(getCounts(accumulation.negative), []);
+    });
   });
   describe('merge', () => {
     it('handles simple (even) case', () => {

packages/sdk-metrics/test/aggregator/Histogram.test.ts

@@ -257,6 +257,19 @@ describe('HistogramAccumulation', () => {
         accumulation.record(value);
       }
     });
+
+    it('ignores NaN', () => {
+      const accumulation = new HistogramAccumulation([0, 0], [1, 10, 100]);
+
+      accumulation.record(NaN);
+
+      const pointValue = accumulation.toPointValue();
+      assert.strictEqual(pointValue.max, -Infinity);
+      assert.strictEqual(pointValue.min, Infinity);
+      assert.strictEqual(pointValue.sum, 0);
+      assert.strictEqual(pointValue.count, 0);
+      assert.deepStrictEqual(pointValue.buckets.counts, [0, 0, 0, 0]);
+    });
   });
 
   describe('setStartTime', () => {