chore(maintenance): migrate metrics utility to biome (#2816)

Co-authored-by: Andrea Amorosi <dreamorosi@gmail.com>

Author: daschaa

packages/metrics/package.json

@@ -19,8 +19,8 @@
     "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/metrics#readme",
@@ -52,10 +52,7 @@
         "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",
@@ -74,9 +71,7 @@
       "optional": true
     }
   },
-  "files": [
-    "lib"
-  ],
+  "files": ["lib"],
   "repository": {
     "type": "git",
     "url": "git+https://github.com/aws-powertools/powertools-lambda-typescript.git"
@@ -87,12 +82,5 @@
   "dependencies": {
     "@aws-lambda-powertools/commons": "^2.5.0"
   },
-  "keywords": [
-    "aws",
-    "lambda",
-    "powertools",
-    "metrics",
-    "serverless",
-    "nodejs"
-  ]
+  "keywords": ["aws", "lambda", "powertools", "metrics", "serverless", "nodejs"]
 }

packages/metrics/src/Metrics.ts

@@ -1,28 +1,28 @@
-import type { Callback, Context, Handler } from 'aws-lambda';
 import { Console } from 'node:console';
 import { Utility } from '@aws-lambda-powertools/commons';
 import type { HandlerMethodDecorator } from '@aws-lambda-powertools/commons/types';
+import type { Callback, Context, Handler } from 'aws-lambda';
 import { EnvironmentVariablesService } from './config/EnvironmentVariablesService.js';
 import {
+  COLD_START_METRIC,
+  DEFAULT_NAMESPACE,
   MAX_DIMENSION_COUNT,
   MAX_METRICS_SIZE,
-  DEFAULT_NAMESPACE,
-  COLD_START_METRIC,
   MAX_METRIC_VALUES_SIZE,
-  MetricUnit as MetricUnits,
   MetricResolution as MetricResolutions,
+  MetricUnit as MetricUnits,
 } from './constants.js';
-import {
-  type MetricsOptions,
-  type Dimensions,
-  type EmfOutput,
-  type StoredMetrics,
-  type ExtraOptions,
-  type MetricDefinition,
-  type ConfigServiceInterface,
-  type MetricsInterface,
-  type MetricUnit,
-  type MetricResolution,
+import type {
+  ConfigServiceInterface,
+  Dimensions,
+  EmfOutput,
+  ExtraOptions,
+  MetricDefinition,
+  MetricResolution,
+  MetricUnit,
+  MetricsInterface,
+  MetricsOptions,
+  StoredMetrics,
 } from './types/index.js';
 
 /**
@@ -167,9 +167,9 @@ class Metrics extends Utility implements MetricsInterface {
    */
   public addDimensions(dimensions: { [key: string]: string }): void {
     const newDimensions = { ...this.dimensions };
-    Object.keys(dimensions).forEach((dimensionName) => {
+    for (const dimensionName of Object.keys(dimensions)) {
       newDimensions[dimensionName] = dimensions[dimensionName];
-    });
+    }
     if (Object.keys(newDimensions).length > MAX_DIMENSION_COUNT) {
       throw new RangeError(
         `Unable to add ${
@@ -337,10 +337,7 @@ class Metrics extends Utility implements MetricsInterface {
     }
 
     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
@@ -359,8 +356,6 @@ class Metrics extends Utility implements MetricsInterface {
         let result: unknown;
         try {
           result = await originalMethod.apply(this, [event, context, callback]);
-        } catch (error) {
-          throw error;
         } finally {
           metricsRef.publishStoredMetrics();
         }
@@ -598,9 +593,8 @@ class Metrics extends Utility implements MetricsInterface {
       }
 
       return false;
-    } else {
-      return true;
     }
+    return true;
   }
 
   /**

packages/metrics/src/config/EnvironmentVariablesService.ts

@@ -1,5 +1,5 @@
-import type { 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/metrics/src/middleware/middy.ts

@@ -1,10 +1,10 @@
 import { METRICS_KEY } from '@aws-lambda-powertools/commons';
-import type { Metrics } from '../Metrics.js';
-import type { ExtraOptions } from '../types/Metrics.js';
 import type {
   MiddlewareLikeObj,
   MiddyLikeRequest,
 } from '@aws-lambda-powertools/commons/types';
+import type { Metrics } from '../Metrics.js';
+import type { ExtraOptions } from '../types/Metrics.js';
 
 /**
  * A middy middleware automating capture of metadata and annotations on segments or subsegments for a Lambda Handler.
@@ -38,7 +38,7 @@ const logMetrics = (
   target: Metrics | Metrics[],
   options: ExtraOptions = {}
 ): MiddlewareLikeObj => {
-  const metricsInstances = target instanceof Array ? target : [target];
+  const metricsInstances = Array.isArray(target) ? target : [target];
 
   /**
    * Set the cleanup function to be called in case other middlewares return early.
@@ -53,7 +53,7 @@ const logMetrics = (
   };
 
   const logMetricsBefore = async (request: MiddyLikeRequest): Promise<void> => {
-    metricsInstances.forEach((metrics: Metrics) => {
+    for (const metrics of metricsInstances) {
       metrics.setFunctionName(request.context.functionName);
       const { throwOnEmptyMetrics, defaultDimensions, captureColdStartMetric } =
         options;
@@ -66,15 +66,15 @@ const logMetrics = (
       if (captureColdStartMetric) {
         metrics.captureColdStartMetric();
       }
-    });
+    }
 
     setCleanupFunction(request);
   };
 
   const logMetricsAfterOrError = async (): Promise<void> => {
-    metricsInstances.forEach((metrics: Metrics) => {
+    for (const metrics of metricsInstances) {
       metrics.publishStoredMetrics();
-    });
+    }
   };
 
   return {

packages/metrics/src/types/Metrics.ts

@@ -1,5 +1,8 @@
+import type {
+  MetricResolution as MetricResolutionList,
+  MetricUnit as MetricUnitList,
+} from '../constants.js';
 import type { ConfigServiceInterface } from './ConfigServiceInterface.js';
-import { MetricResolution, MetricUnit } from '../constants.js';
 
 type Dimensions = Record<string, string>;
 
@@ -49,9 +52,9 @@ type ExtraOptions = {
 };
 
 type MetricResolution =
-  (typeof MetricResolution)[keyof typeof MetricResolution];
+  (typeof MetricResolutionList)[keyof typeof MetricResolutionList];
 
-type MetricUnit = (typeof MetricUnit)[keyof typeof MetricUnit];
+type MetricUnit = (typeof MetricUnitList)[keyof typeof MetricUnitList];
 
 type StoredMetric = {
   name: string;

packages/metrics/src/types/MetricsInterface.ts

@@ -1,11 +1,11 @@
-import type { Metrics } from '../Metrics.js';
 import type { HandlerMethodDecorator } from '@aws-lambda-powertools/commons/types';
+import type { Metrics } from '../Metrics.js';
 import type {
-  EmfOutput,
   Dimensions,
-  MetricsOptions,
+  EmfOutput,
   MetricResolution,
   MetricUnit,
+  MetricsOptions,
 } from './Metrics.js';
 
 interface MetricsInterface {

packages/metrics/tests/e2e/basicFeatures.decorator.test.functionCode.ts

@@ -1,7 +1,7 @@
-import { Metrics, MetricUnit } from '../../src/index.js';
-import type { MetricUnit as MetricUnitType } from '../../src/types/index.js';
-import type { Context } from 'aws-lambda';
 import type { LambdaInterface } from '@aws-lambda-powertools/commons/types';
+import type { Context } from 'aws-lambda';
+import { MetricUnit, Metrics } from '../../src/index.js';
+import type { MetricUnit as MetricUnitType } from '../../src/types/index.js';
 
 const namespace = process.env.EXPECTED_NAMESPACE ?? 'CdkExample';
 const serviceName =
@@ -35,7 +35,7 @@ class Lambda implements LambdaInterface {
   // eslint-disable-next-line @typescript-eslint/ban-ts-comment
   // @ts-ignore
   public async handler(_event: unknown, _context: Context): Promise<void> {
-    metrics.addMetric(metricName, metricUnit, parseInt(metricValue));
+    metrics.addMetric(metricName, metricUnit, Number.parseInt(metricValue));
     metrics.addDimension(
       Object.entries(JSON.parse(extraDimension))[0][0],
       Object.entries(JSON.parse(extraDimension))[0][1] as string
@@ -54,7 +54,7 @@ class Lambda implements LambdaInterface {
     metricWithItsOwnDimensions.addMetric(
       singleMetricName,
       singleMetricUnit,
-      parseInt(singleMetricValue)
+      Number.parseInt(singleMetricValue)
     );
   }
 }

packages/metrics/tests/e2e/basicFeatures.decorators.test.ts

@@ -3,27 +3,27 @@
  *
  * @group e2e/metrics/decorator
  */
+import { join } from 'node:path';
 import {
-  invokeFunction,
   TestStack,
+  invokeFunction,
 } from '@aws-lambda-powertools/testing-utils';
 import {
   CloudWatchClient,
   GetMetricStatisticsCommand,
 } from '@aws-sdk/client-cloudwatch';
-import { join } from 'node:path';
 import { getMetrics, sortDimensions } from '../helpers/metricsUtils.js';
 import { MetricsTestNodejsFunction } from '../helpers/resources.js';
 import {
-  commonEnvironmentVars,
   ONE_MINUTE,
   RESOURCE_NAME_PREFIX,
   SETUP_TIMEOUT,
   TEARDOWN_TIMEOUT,
   TEST_CASE_TIMEOUT,
+  commonEnvironmentVars,
 } from './constants.js';
 
-describe(`Metrics E2E tests, basic features decorator usage`, () => {
+describe('Metrics E2E tests, basic features decorator usage', () => {
   const testStack = new TestStack({
     stackNameProps: {
       stackNamePrefix: RESOURCE_NAME_PREFIX,
@@ -205,7 +205,7 @@ describe(`Metrics E2E tests, basic features decorator usage`, () => {
           ? metricStat.Datapoints[0]
           : {};
         expect(singleDataPoint?.Sum).toBeGreaterThanOrEqual(
-          parseInt(expectedMetricValue) * invocations
+          Number.parseInt(expectedMetricValue) * invocations
         );
       },
       TEST_CASE_TIMEOUT

packages/metrics/tests/e2e/basicFeatures.manual.test.functionCode.ts

@@ -1,6 +1,6 @@
-import { Metrics, MetricUnit } from '../../src/index.js';
-import type { MetricUnit as MetricUnitType } from '../../src/types/index.js';
 import type { Context } from 'aws-lambda';
+import { MetricUnit, Metrics } from '../../src/index.js';
+import type { MetricUnit as MetricUnitType } from '../../src/types/index.js';
 
 const namespace = process.env.EXPECTED_NAMESPACE ?? 'CdkExample';
 const serviceName =
@@ -32,7 +32,7 @@ export const handler = async (
   metrics.captureColdStartMetric();
   metrics.throwOnEmptyMetrics();
   metrics.setDefaultDimensions(JSON.parse(defaultDimensions));
-  metrics.addMetric(metricName, metricUnit, parseInt(metricValue));
+  metrics.addMetric(metricName, metricUnit, Number.parseInt(metricValue));
   metrics.addDimension(
     Object.entries(JSON.parse(extraDimension))[0][0],
     Object.entries(JSON.parse(extraDimension))[0][1] as string
@@ -46,7 +46,7 @@ export const handler = async (
   metricWithItsOwnDimensions.addMetric(
     singleMetricName,
     singleMetricUnit,
-    parseInt(singleMetricValue)
+    Number.parseInt(singleMetricValue)
   );
 
   metrics.publishStoredMetrics();

packages/metrics/tests/e2e/basicFeatures.manual.test.ts

@@ -3,27 +3,27 @@
  *
  * @group e2e/metrics/standardFunctions
  */
+import { join } from 'node:path';
 import {
-  invokeFunction,
   TestStack,
+  invokeFunction,
 } from '@aws-lambda-powertools/testing-utils';
 import {
   CloudWatchClient,
   GetMetricStatisticsCommand,
 } from '@aws-sdk/client-cloudwatch';
-import { join } from 'node:path';
 import { getMetrics, sortDimensions } from '../helpers/metricsUtils.js';
 import { MetricsTestNodejsFunction } from '../helpers/resources.js';
 import {
-  commonEnvironmentVars,
   ONE_MINUTE,
   RESOURCE_NAME_PREFIX,
   SETUP_TIMEOUT,
   TEARDOWN_TIMEOUT,
   TEST_CASE_TIMEOUT,
+  commonEnvironmentVars,
 } from './constants.js';
 
-describe(`Metrics E2E tests, manual usage`, () => {
+describe('Metrics E2E tests, manual usage', () => {
   const testStack = new TestStack({
     stackNameProps: {
       stackNamePrefix: RESOURCE_NAME_PREFIX,
@@ -191,7 +191,7 @@ describe(`Metrics E2E tests, manual usage`, () => {
           ? metricStat.Datapoints[0]
           : {};
         expect(singleDataPoint.Sum).toBeGreaterThanOrEqual(
-          parseInt(expectedMetricValue) * invocations
+          Number.parseInt(expectedMetricValue) * invocations
         );
       },
       TEST_CASE_TIMEOUT