perf: remove unnecessary base64 encode+decode from OTLP export

CHANGELOG.md

@@ -15,6 +15,8 @@ For experimental package changes, see the [experimental CHANGELOG](experimental/
 
 ### :rocket: (Enhancement)
 
+* perf(otlp-transformer): skip unnecessary base64 encode of span contexts [#4343](https://github.com/open-telemetry/opentelemetry-js/pull/4343) @seemk
+
 ### :books: (Refine Doc)
 
 ### :house: (Internal)

experimental/packages/otlp-transformer/src/common/index.ts

@@ -16,7 +16,7 @@
 
 import type { OtlpEncodingOptions, Fixed64, LongBits } from './types';
 import { HrTime } from '@opentelemetry/api';
-import { hexToBase64, hrTimeToNanoseconds } from '@opentelemetry/core';
+import { hexToBinary, hrTimeToNanoseconds } from '@opentelemetry/core';
 
 const NANOSECONDS = BigInt(1_000_000_000);
 
@@ -44,10 +44,12 @@ const encodeTimestamp =
   typeof BigInt !== 'undefined' ? encodeAsString : hrTimeToNanoseconds;
 
 export type HrTimeEncodeFunction = (hrTime: HrTime) => Fixed64;
-export type SpanContextEncodeFunction = (spanContext: string) => string;
+export type SpanContextEncodeFunction = (
+  spanContext: string
+) => string | Uint8Array;
 export type OptionalSpanContextEncodeFunction = (
   spanContext: string | undefined
-) => string | undefined;
+) => string | Uint8Array | undefined;
 
 export interface Encoder {
   encodeHrTime: HrTimeEncodeFunction;
@@ -59,15 +61,15 @@ function identity<T>(value: T): T {
   return value;
 }
 
-function optionalHexToBase64(str: string | undefined): string | undefined {
+function optionalHexToBinary(str: string | undefined): Uint8Array | undefined {
   if (str === undefined) return undefined;
-  return hexToBase64(str);
+  return hexToBinary(str);
 }
 
 const DEFAULT_ENCODER: Encoder = {
   encodeHrTime: encodeAsLongBits,
-  encodeSpanContext: hexToBase64,
-  encodeOptionalSpanContext: optionalHexToBase64,
+  encodeSpanContext: hexToBinary,
+  encodeOptionalSpanContext: optionalHexToBinary,
 };
 
 export function getOtlpEncoder(options?: OtlpEncodingOptions): Encoder {
@@ -79,7 +81,7 @@ export function getOtlpEncoder(options?: OtlpEncodingOptions): Encoder {
   const useHex = options.useHex ?? false;
   return {
     encodeHrTime: useLongBits ? encodeAsLongBits : encodeTimestamp,
-    encodeSpanContext: useHex ? identity : hexToBase64,
-    encodeOptionalSpanContext: useHex ? identity : optionalHexToBase64,
+    encodeSpanContext: useHex ? identity : hexToBinary,
+    encodeOptionalSpanContext: useHex ? identity : optionalHexToBinary,
   };
 }

experimental/packages/otlp-transformer/src/logs/types.ts

@@ -92,10 +92,10 @@ export interface ILogRecord {
   flags?: number;
 
   /** LogRecord traceId */
-  traceId?: string;
+  traceId?: string | Uint8Array;
 
   /** LogRecord spanId */
-  spanId?: string;
+  spanId?: string | Uint8Array;
 }
 
 /**

experimental/packages/otlp-transformer/src/metrics/types.ts

@@ -287,10 +287,10 @@ export interface IExemplar {
   asInt?: number;
 
   /** Exemplar spanId */
-  spanId?: string;
+  spanId?: string | Uint8Array;
 
   /** Exemplar traceId */
-  traceId?: string;
+  traceId?: string | Uint8Array;
 }
 
 /**

experimental/packages/otlp-transformer/src/trace/types.ts

@@ -63,16 +63,16 @@ export interface IScopeSpans {
 /** Properties of a Span. */
 export interface ISpan {
   /** Span traceId */
-  traceId: string;
+  traceId: string | Uint8Array;
 
   /** Span spanId */
-  spanId: string;
+  spanId: string | Uint8Array;
 
   /** Span traceState */
   traceState?: string | null;
 
   /** Span parentSpanId */
-  parentSpanId?: string;
+  parentSpanId?: string | Uint8Array;
 
   /** Span name */
   name: string;
@@ -181,10 +181,10 @@ export interface IEvent {
 /** Properties of a Link. */
 export interface ILink {
   /** Link traceId */
-  traceId: string;
+  traceId: string | Uint8Array;
 
   /** Link spanId */
-  spanId: string;
+  spanId: string | Uint8Array;
 
   /** Link traceState */
   traceState?: string;

experimental/packages/otlp-transformer/test/common.test.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { hexToBase64 } from '@opentelemetry/core';
+import { hexToBinary } from '@opentelemetry/core';
 import { getOtlpEncoder } from '../src';
 import { toAnyValue } from '../src/common/internal';
 import * as assert from 'assert';
@@ -70,19 +70,19 @@ describe('common', () => {
   });
 
   describe('otlp encoder', () => {
-    it('defaults to long timestamps and base64 encoding given no options', () => {
+    it('defaults to long timestamps and binary encoding given no options', () => {
       const encoder = getOtlpEncoder();
       assert.deepStrictEqual(encoder.encodeHrTime([1697978649, 99870675]), {
         low: 3352011219,
         high: 395341461,
       });
       assert.deepStrictEqual(
         encoder.encodeSpanContext(traceId),
-        hexToBase64(traceId)
+        hexToBinary(traceId)
       );
       assert.deepStrictEqual(
         encoder.encodeOptionalSpanContext(spanId),
-        hexToBase64(spanId)
+        hexToBinary(spanId)
       );
       assert.deepStrictEqual(
         encoder.encodeOptionalSpanContext(undefined),
@@ -98,11 +98,11 @@ describe('common', () => {
       });
       assert.deepStrictEqual(
         encoder.encodeSpanContext(traceId),
-        hexToBase64(traceId)
+        hexToBinary(traceId)
       );
       assert.deepStrictEqual(
         encoder.encodeOptionalSpanContext(spanId),
-        hexToBase64(spanId)
+        hexToBinary(spanId)
       );
       assert.deepStrictEqual(
         encoder.encodeOptionalSpanContext(undefined),

experimental/packages/otlp-transformer/test/logs.test.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 import { HrTime, TraceFlags } from '@opentelemetry/api';
-import { InstrumentationScope, hexToBase64 } from '@opentelemetry/core';
+import { InstrumentationScope, hexToBinary } from '@opentelemetry/core';
 import { Resource } from '@opentelemetry/resources';
 import * as assert from 'assert';
 import {
@@ -28,8 +28,8 @@ import { SeverityNumber } from '@opentelemetry/api-logs';
 function createExpectedLogJson(useHex: boolean): IExportLogsServiceRequest {
   const traceId = useHex
     ? '00000000000000000000000000000001'
-    : hexToBase64('00000000000000000000000000000001');
-  const spanId = useHex ? '0000000000000002' : hexToBase64('0000000000000002');
+    : hexToBinary('00000000000000000000000000000001');
+  const spanId = useHex ? '0000000000000002' : hexToBinary('0000000000000002');
 
   return {
     resourceLogs: [

experimental/packages/otlp-transformer/test/trace.test.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 import { SpanKind, SpanStatusCode, TraceFlags } from '@opentelemetry/api';
-import { TraceState, hexToBase64 } from '@opentelemetry/core';
+import { TraceState, hexToBinary } from '@opentelemetry/core';
 import { Resource } from '@opentelemetry/resources';
 import { ReadableSpan } from '@opentelemetry/sdk-trace-base';
 import * as assert from 'assert';
@@ -41,17 +41,17 @@ function createExpectedSpanJson(options: OtlpEncodingOptions) {
 
   const traceId = useHex
     ? '00000000000000000000000000000001'
-    : hexToBase64('00000000000000000000000000000001');
-  const spanId = useHex ? '0000000000000002' : hexToBase64('0000000000000002');
+    : hexToBinary('00000000000000000000000000000001');
+  const spanId = useHex ? '0000000000000002' : hexToBinary('0000000000000002');
   const parentSpanId = useHex
     ? '0000000000000001'
-    : hexToBase64('0000000000000001');
+    : hexToBinary('0000000000000001');
   const linkSpanId = useHex
     ? '0000000000000003'
-    : hexToBase64('0000000000000003');
+    : hexToBinary('0000000000000003');
   const linkTraceId = useHex
     ? '00000000000000000000000000000002'
-    : hexToBase64('00000000000000000000000000000002');
+    : hexToBinary('00000000000000000000000000000002');
 
   return {
     resourceSpans: [

packages/opentelemetry-core/src/common/hex-to-binary.ts

@@ -0,0 +1,43 @@
+/*
+ * Copyright The 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.
+ */
+
+function intValue(charCode: number): number {
+  // 0-9
+  if (charCode >= 48 && charCode <= 57) {
+    return charCode - 48;
+  }
+
+  // a-f
+  if (charCode >= 97 && charCode <= 102) {
+    return charCode - 87;
+  }
+
+  // A-F
+  return charCode - 55;
+}
+
+export function hexToBinary(hexStr: string): Uint8Array {
+  const buf = new Uint8Array(hexStr.length / 2);
+  let offset = 0;
+
+  for (let i = 0; i < hexStr.length; i += 2) {
+    const hi = intValue(hexStr.charCodeAt(i));
+    const lo = intValue(hexStr.charCodeAt(i + 1));
+    buf[offset++] = (hi << 4) | lo;
+  }
+
+  return buf;
+}

packages/opentelemetry-core/src/index.ts

@@ -21,6 +21,7 @@ export * from './common/global-error-handler';
 export * from './common/logging-error-handler';
 export * from './common/time';
 export * from './common/types';
+export * from './common/hex-to-binary';
 export * from './ExportResult';
 export * as baggageUtils from './baggage/utils';
 export * from './platform';

packages/opentelemetry-core/src/platform/browser/hex-to-base64.ts

@@ -13,13 +13,9 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
+import { hexToBinary } from '../../common/hex-to-binary';
+
 export function hexToBase64(hexStr: string): string {
-  const hexStrLen = hexStr.length;
-  let hexAsciiCharsStr = '';
-  for (let i = 0; i < hexStrLen; i += 2) {
-    const hexPair = hexStr.substring(i, i + 2);
-    const hexVal = parseInt(hexPair, 16);
-    hexAsciiCharsStr += String.fromCharCode(hexVal);
-  }
-  return btoa(hexAsciiCharsStr);
+  return btoa(String.fromCharCode(...hexToBinary(hexStr)));
 }

packages/opentelemetry-core/src/platform/node/hex-to-base64.ts

@@ -13,40 +13,8 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-function intValue(charCode: number): number {
-  // 0-9
-  if (charCode >= 48 && charCode <= 57) {
-    return charCode - 48;
-  }
-
-  // a-f
-  if (charCode >= 97 && charCode <= 102) {
-    return charCode - 87;
-  }
-
-  // A-F
-  return charCode - 55;
-}
-
-const buf8 = Buffer.alloc(8);
-const buf16 = Buffer.alloc(16);
+import { hexToBinary } from '../../common/hex-to-binary';
 
 export function hexToBase64(hexStr: string): string {
-  let buf;
-  if (hexStr.length === 16) {
-    buf = buf8;
-  } else if (hexStr.length === 32) {
-    buf = buf16;
-  } else {
-    buf = Buffer.alloc(hexStr.length / 2);
-  }
-  let offset = 0;
-
-  for (let i = 0; i < hexStr.length; i += 2) {
-    const hi = intValue(hexStr.charCodeAt(i));
-    const lo = intValue(hexStr.charCodeAt(i + 1));
-    buf.writeUInt8((hi << 4) | lo, offset++);
-  }
-
-  return buf.toString('base64');
+  return Buffer.from(hexToBinary(hexStr)).toString('base64');
 }