chore(maintenance): migrate tracer utility to biome

packages/tracer/package.json

@@ -20,8 +20,8 @@
     "build:cjs": "tsc --build tsconfig.json && echo '{ \"type\": \"commonjs\" }' > lib/cjs/package.json",
     "build:esm": "tsc --build tsconfig.esm.json && echo '{ \"type\": \"module\" }' > lib/esm/package.json",
     "build": "npm run build:esm & npm run build:cjs",
-    "lint": "eslint --ext .ts,.js --no-error-on-unmatched-pattern .",
-    "lint-fix": "eslint --fix --ext .ts,.js --no-error-on-unmatched-pattern .",
+    "lint": "biome lint .",
+    "lint:fix": "biome check --write .",
     "prepack": "node ../../.github/scripts/release_patch_package_json.js ."
   },
   "homepage": "https://github.com/aws-powertools/powertools-lambda-typescript/tree/main/packages/tracer#readme",
@@ -69,17 +69,12 @@
         "lib/cjs/middleware/middy.d.ts",
         "lib/esm/middleware/middy.d.ts"
       ],
-      "types": [
-        "lib/cjs/types/index.d.ts",
-        "lib/esm/types/index.d.ts"
-      ]
+      "types": ["lib/cjs/types/index.d.ts", "lib/esm/types/index.d.ts"]
     }
   },
   "types": "./lib/cjs/index.d.ts",
   "main": "./lib/cjs/index.js",
-  "files": [
-    "lib"
-  ],
+  "files": ["lib"],
   "repository": {
     "type": "git",
     "url": "git+https://github.com/aws-powertools/powertools-lambda-typescript.git"

packages/tracer/src/Tracer.ts

@@ -1,24 +1,24 @@
-import type { Handler } from 'aws-lambda';
 import { Utility } from '@aws-lambda-powertools/commons';
 import type {
   AsyncHandler,
-  SyncHandler,
   HandlerMethodDecorator,
+  SyncHandler,
 } from '@aws-lambda-powertools/commons/types';
+import type { Handler } from 'aws-lambda';
+import type { Segment, Subsegment } from 'aws-xray-sdk-core';
+import xraySdk from 'aws-xray-sdk-core';
 import { EnvironmentVariablesService } from './config/EnvironmentVariablesService.js';
+import { ProviderService } from './provider/ProviderService.js';
 import type { ConfigServiceInterface } from './types/ConfigServiceInterface.js';
+import type { ProviderServiceInterface } from './types/ProviderService.js';
 import type {
-  TracerInterface,
-  TracerOptions,
   AnyClass,
-  MethodDecorator,
   CaptureLambdaHandlerOptions,
   CaptureMethodOptions,
+  MethodDecorator,
+  TracerInterface,
+  TracerOptions,
 } from './types/Tracer.js';
-import { ProviderService } from './provider/ProviderService.js';
-import type { ProviderServiceInterface } from './types/ProviderService.js';
-import type { Segment, Subsegment } from 'aws-xray-sdk-core';
-import xraySdk from 'aws-xray-sdk-core';
 const { Subsegment: XraySubsegment } = xraySdk;
 
 /**
@@ -372,22 +372,16 @@ class Tracer extends Utility implements TracerInterface {
     options?: CaptureLambdaHandlerOptions
   ): HandlerMethodDecorator {
     return (_target, _propertyKey, descriptor) => {
-      /**
-       * The descriptor.value is the method this decorator decorates, it cannot be undefined.
-       */
-      // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+      // biome-ignore lint/style/noNonNullAssertion: The descriptor.value is the method this decorator decorates, it cannot be undefined.
       const originalMethod = descriptor.value!;
 
       // eslint-disable-next-line @typescript-eslint/no-this-alias
       const tracerRef = this;
       // Use a function() {} instead of an () => {} arrow function so that we can
       // access `myClass` as `this` in a decorated `myClass.myMethod()`.
       descriptor.value = function (this: Handler, event, context, callback) {
-        // eslint-disable-next-line @typescript-eslint/no-this-alias
-        const handlerRef: Handler = this;
-
         if (!tracerRef.isTracingEnabled()) {
-          return originalMethod.apply(handlerRef, [event, context, callback]);
+          return originalMethod.apply(this, [event, context, callback]);
         }
 
         return tracerRef.provider.captureAsyncFunc(
@@ -397,7 +391,7 @@ class Tracer extends Utility implements TracerInterface {
             tracerRef.addServiceNameAnnotation();
             let result: unknown;
             try {
-              result = await originalMethod.apply(handlerRef, [
+              result = await originalMethod.apply(this, [
                 event,
                 context,
                 callback,
@@ -413,7 +407,7 @@ class Tracer extends Utility implements TracerInterface {
                 subsegment?.close();
               } catch (error) {
                 console.warn(
-                  `Failed to close or serialize segment %s. We are catching the error but data might be lost.`,
+                  'Failed to close or serialize segment %s. We are catching the error but data might be lost.',
                   subsegment?.name,
                   error
                 );
@@ -469,8 +463,7 @@ class Tracer extends Utility implements TracerInterface {
     options?: CaptureMethodOptions
   ): MethodDecorator<T> {
     return (_target, propertyKey, descriptor) => {
-      // The descriptor.value is the method this decorator decorates, it cannot be undefined.
-      // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+      // biome-ignore lint/style/noNonNullAssertion: The descriptor.value is the method this decorator decorates, it cannot be undefined.
       const originalMethod = descriptor.value!;
 
       // eslint-disable-next-line @typescript-eslint/no-this-alias
@@ -490,7 +483,8 @@ class Tracer extends Utility implements TracerInterface {
         return tracerRef.provider.captureAsyncFunc(
           subsegmentName,
           async (subsegment) => {
-            let result;
+            // biome-ignore lint/suspicious/noExplicitAny: we don't know the type of the result because we're decorating arbitrary functions
+            let result: any;
             try {
               result = await originalMethod.apply(this, [...args]);
               if (options?.captureResponse ?? true) {
@@ -505,7 +499,7 @@ class Tracer extends Utility implements TracerInterface {
                 subsegment?.close();
               } catch (error) {
                 console.warn(
-                  `Failed to close or serialize segment %s. We are catching the error but data might be lost.`,
+                  'Failed to close or serialize segment %s. We are catching the error but data might be lost.',
                   subsegment?.name,
                   error
                 );
@@ -702,7 +696,7 @@ class Tracer extends Utility implements TracerInterface {
   public setSegment(segment: Segment | Subsegment): void {
     if (!this.isTracingEnabled()) return;
 
-    return this.provider.setSegment(segment);
+    this.provider.setSegment(segment);
   }
 
   /**

packages/tracer/src/config/EnvironmentVariablesService.ts

@@ -1,5 +1,5 @@
-import { ConfigServiceInterface } from '../types/ConfigServiceInterface.js';
 import { EnvironmentVariablesService as CommonEnvironmentVariablesService } from '@aws-lambda-powertools/commons';
+import type { ConfigServiceInterface } from '../types/ConfigServiceInterface.js';
 
 class EnvironmentVariablesService
   extends CommonEnvironmentVariablesService

packages/tracer/src/middleware/middy.ts

@@ -1,11 +1,11 @@
 import { TRACER_KEY } from '@aws-lambda-powertools/commons';
-import type { Tracer } from '../Tracer.js';
-import type { Segment, Subsegment } from 'aws-xray-sdk-core';
-import type { CaptureLambdaHandlerOptions } from '../types/Tracer.js';
 import type {
   MiddlewareLikeObj,
   MiddyLikeRequest,
 } from '@aws-lambda-powertools/commons/types';
+import type { Segment, Subsegment } from 'aws-xray-sdk-core';
+import type { Tracer } from '../Tracer.js';
+import type { CaptureLambdaHandlerOptions } from '../types/Tracer.js';
 
 /**
  * A middy middleware automating capture of metadata and annotations on segments or subsegments for a Lambda Handler.
@@ -75,7 +75,7 @@ const captureLambdaHandler = (
       handlerSegment.close();
     } catch (error) {
       console.warn(
-        `Failed to close or serialize segment %s. We are catching the error but data might be lost.`,
+        'Failed to close or serialize segment %s. We are catching the error but data might be lost.',
         handlerSegment.name,
         error
       );

packages/tracer/src/provider/ProviderService.ts

@@ -1,11 +1,11 @@
+import type { Logger, Segment, Subsegment } from 'aws-xray-sdk-core';
+import xraySdk from 'aws-xray-sdk-core';
 import type { Namespace } from 'cls-hooked';
 import type {
-  ProviderServiceInterface,
   ContextMissingStrategy,
   HttpSubsegment,
+  ProviderServiceInterface,
 } from '../types/ProviderService.js';
-import type { Segment, Subsegment, Logger } from 'aws-xray-sdk-core';
-import xraySdk from 'aws-xray-sdk-core';
 const {
   captureAWS,
   captureAWSClient,
@@ -21,16 +21,16 @@ const {
   setDaemonAddress,
   setLogger,
 } = xraySdk;
-import { addUserAgentMiddleware } from '@aws-lambda-powertools/commons';
 import { subscribe } from 'node:diagnostics_channel';
+import http from 'node:http';
+import https from 'node:https';
+import { addUserAgentMiddleware } from '@aws-lambda-powertools/commons';
+import type { DiagnosticsChannel } from 'undici-types';
 import {
   findHeaderAndDecode,
   getOriginURL,
   isHttpSubsegment,
 } from './utilities.js';
-import type { DiagnosticsChannel } from 'undici-types';
-import http from 'node:http';
-import https from 'node:https';
 
 class ProviderService implements ProviderServiceInterface {
   /**
@@ -50,8 +50,7 @@ class ProviderService implements ProviderServiceInterface {
   public captureAWSv3Client<T>(service: T): T {
     addUserAgentMiddleware(service, 'tracer');
 
-    // Type must be aliased as any because of this https://github.com/aws/aws-xray-sdk-node/issues/439#issuecomment-859715660
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    // biome-ignore lint/suspicious/noExplicitAny: Type must be aliased as any because of this https://github.com/aws/aws-xray-sdk-node/issues/439#issuecomment-859715660
     return captureAWSv3Client(service as any);
   }
 
@@ -150,7 +149,7 @@ class ProviderService implements ProviderServiceInterface {
           response: {
             status,
             ...(contentLenght && {
-              content_length: parseInt(contentLenght),
+              content_length: Number.parseInt(contentLenght),
             }),
           },
         };

packages/tracer/src/provider/utilities.ts

@@ -1,6 +1,6 @@
-import type { HttpSubsegment } from '../types/ProviderService.js';
-import type { Segment, Subsegment } from 'aws-xray-sdk-core';
 import { URL } from 'node:url';
+import type { Segment, Subsegment } from 'aws-xray-sdk-core';
+import type { HttpSubsegment } from '../types/ProviderService.js';
 
 const decoder = new TextDecoder();
 

packages/tracer/src/types/ProviderService.ts

@@ -1,5 +1,5 @@
-import type { Namespace } from 'cls-hooked';
 import type { Segment, Subsegment } from 'aws-xray-sdk-core';
+import type { Namespace } from 'cls-hooked';
 
 type ContextMissingStrategy =
   | 'LOG_ERROR'

packages/tracer/src/types/Tracer.ts

@@ -1,6 +1,6 @@
-import type { ConfigServiceInterface } from './ConfigServiceInterface.js';
 import type { HandlerMethodDecorator } from '@aws-lambda-powertools/commons/types';
 import type { Segment, Subsegment } from 'aws-xray-sdk-core';
+import type { ConfigServiceInterface } from './ConfigServiceInterface.js';
 
 /**
  * Options for the tracer class to be used during initialization.
@@ -99,9 +99,9 @@ type CaptureMethodOptions = {
   captureResponse?: boolean;
 };
 
-// eslint-disable-next-line  @typescript-eslint/no-explicit-any
+// biome-ignore lint/suspicious/noExplicitAny: this is a generic type that is intentionally open
 type AnyClassMethod = (...args: any[]) => any;
-// eslint-disable-next-line  @typescript-eslint/no-explicit-any
+// biome-ignore lint/suspicious/noExplicitAny: this is a generic type that is intentionally open
 type AnyClass = new (...args: any[]) => any;
 
 type MethodDecorator<T extends AnyClass> = (
@@ -115,9 +115,9 @@ interface TracerInterface {
   addResponseAsMetadata(data?: unknown, methodName?: string): void;
   addServiceNameAnnotation(): void;
   annotateColdStart(): void;
-  captureAWS<T>(aws: T): void | T;
-  captureAWSv3Client<T>(service: T): void | T;
-  captureAWSClient<T>(service: T): void | T;
+  captureAWS<T>(aws: T): undefined | T;
+  captureAWSv3Client<T>(service: T): undefined | T;
+  captureAWSClient<T>(service: T): undefined | T;
   captureLambdaHandler(
     options?: CaptureLambdaHandlerOptions
   ): HandlerMethodDecorator;

packages/tracer/tests/e2e/allFeatures.decorator.test.functionCode.ts

@@ -1,6 +1,6 @@
-import { Tracer } from '../../src/Tracer.js';
 import type { Callback, Context } from 'aws-lambda';
 import AWS from 'aws-sdk';
+import { Tracer } from '../../src/Tracer.js';
 import { httpRequest } from '../helpers/httpRequest.js';
 
 const serviceName =
@@ -41,7 +41,7 @@ export class MyFunctionBase {
     event: CustomEvent,
     _context: Context,
     _callback: Callback<unknown>
-  ): void | Promise<unknown> {
+  ): unknown {
     tracer.putAnnotation(customAnnotationKey, customAnnotationValue);
     tracer.putMetadata(customMetadataKey, customMetadataValue);
 
@@ -84,7 +84,7 @@ class MyFunctionWithDecorator extends MyFunctionBase {
     event: CustomEvent,
     _context: Context,
     _callback: Callback<unknown>
-  ): void | Promise<unknown> {
+  ): unknown {
     return super.handler(event, _context, _callback);
   }
 
@@ -103,7 +103,7 @@ class MyFunctionWithDecoratorCaptureResponseFalse extends MyFunctionBase {
     event: CustomEvent,
     _context: Context,
     _callback: Callback<unknown>
-  ): void | Promise<unknown> {
+  ): unknown {
     return super.handler(event, _context, _callback);
   }
 

packages/tracer/tests/e2e/allFeatures.decorator.test.ts

@@ -3,9 +3,9 @@
  *
  * @group e2e/tracer/decorator
  */
+import { join } from 'node:path';
 import { TestStack } from '@aws-lambda-powertools/testing-utils';
 import { TestDynamodbTable } from '@aws-lambda-powertools/testing-utils/resources/dynamodb';
-import { join } from 'node:path';
 import { TracerTestNodejsFunction } from '../helpers/resources.js';
 import {
   assertAnnotation,
@@ -19,11 +19,11 @@ import {
   splitSegmentsByName,
 } from '../helpers/tracesUtils.js';
 import {
-  commonEnvironmentVars,
   RESOURCE_NAME_PREFIX,
   SETUP_TIMEOUT,
   TEARDOWN_TIMEOUT,
   TEST_CASE_TIMEOUT,
+  commonEnvironmentVars,
 } from './constants.js';
 
 /**
@@ -35,7 +35,7 @@ import {
  * Each stack must use a unique `serviceName` as it's used to for retrieving the trace.
  * Using the same one will result in traces from different test cases mixing up.
  */
-describe(`Tracer E2E tests, all features with decorator instantiation`, () => {
+describe('Tracer E2E tests, all features with decorator instantiation', () => {
   const testStack = new TestStack({
     stackNameProps: {
       stackNamePrefix: RESOURCE_NAME_PREFIX,
@@ -265,14 +265,14 @@ describe(`Tracer E2E tests, all features with decorator instantiation`, () => {
         if (!metadata) {
           fail('metadata is missing');
         }
-        expect(metadata['AllFlagsOn'][expectedCustomMetadataKey]).toEqual(
+        expect(metadata.AllFlagsOn[expectedCustomMetadataKey]).toEqual(
           expectedCustomMetadataValue
         );
 
         const shouldThrowAnError = i === invocationCount - 1;
         if (!shouldThrowAnError) {
           // Assert that the metadata object contains the response
-          expect(metadata['AllFlagsOn']['index.handler response']).toEqual(
+          expect(metadata.AllFlagsOn['index.handler response']).toEqual(
             expectedCustomResponseValue
           );
         }

packages/tracer/tests/e2e/allFeatures.manual.test.functionCode.ts

@@ -1,7 +1,7 @@
-import { Tracer } from '../../src/index.js';
 import type { Context } from 'aws-lambda';
 import AWS from 'aws-sdk';
 import type { Subsegment } from 'aws-xray-sdk-core';
+import { Tracer } from '../../src/index.js';
 import { httpRequest } from '../helpers/httpRequest.js';
 
 const serviceName =