feat(logger): add esmodule support (#1734)

* feat(logger): add esm build output

* fix(Logger): Remove barrel files update references

* test(Logger): update jest/ts-jest to use ESM

* chore(Logger): remove unused lodash.merge

* fix(logger): reinstate lodash.merge

* chore(logger): revert TS assertion

* chore(logger): revert format changes

* chore(logger): update postbuild to remove incremental tsbuildinfo files

* fix(logger): correct reference to types output

* feat(logging): add middleware export

* chore(logger): replace postbuild script with echo statement

* feat(logger): add typesVersions property and barrel files to /types

* chore(logger): file not used, can be added back if needed

* chore(logger): add space back to README

* chore(logger): revert space in README

.gitignore

@@ -49,4 +49,5 @@ site
 tmp
 
 # TS build files
-tsconfig.tsbuildinfo
+tsconfig.tsbuildinfo
+tsconfig.esm.tsbuildinfo

packages/logger/README.md

@@ -114,4 +114,4 @@ Credits for the Powertools for AWS Lambda (TypeScript) idea go to [DAZN](https:/
 
 ## License
 
-This library is licensed under the MIT-0 License. See the LICENSE file.
+This library is licensed under the MIT-0 License. See the LICENSE file.

packages/logger/jest.config.js → packages/logger/jest.config.cjs

@@ -4,9 +4,17 @@ module.exports = {
     color: 'cyan',
   },
   runner: 'groups',
-  preset: 'ts-jest',
+  extensionsToTreatAsEsm: ['.ts'],
+  moduleNameMapper: {
+    '^(\\.{1,2}/.*)\\.js$': '$1',
+  },
   transform: {
-    '^.+\\.ts?$': 'ts-jest',
+    '^.+\\.[tj]sx?$': [
+      'ts-jest',
+      {
+        useESM: true,
+      },
+    ],
   },
   moduleFileExtensions: ['js', 'ts'],
   collectCoverageFrom: ['**/src/**/*.ts', '!**/node_modules/**'],

packages/logger/package.json

@@ -16,19 +16,55 @@
     "test:e2e:nodejs18x": "RUNTIME=nodejs18x jest --group=e2e",
     "test:e2e": "jest --group=e2e",
     "watch": "jest --watch --group=unit",
-    "build": "tsc --build --force",
+    "build:cjs": "tsc --build --force && echo '{ \"type\": \"commonjs\" }' > lib/cjs/package.json",
+    "build:esm": "tsc --project 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 .",
     "prebuild": "rimraf ./lib",
+    "postbuild": "rimraf ./lib/*.tsbuildinfo",
     "prepack": "node ../../.github/scripts/release_patch_package_json.js ."
   },
   "lint-staged": {
     "*.{js,ts}": "npm run lint-fix"
   },
   "homepage": "https://github.com/aws-powertools/powertools-lambda-typescript/tree/main/packages/logger#readme",
   "license": "MIT-0",
-  "main": "./lib/index.js",
-  "types": "./lib/index.d.ts",
+  "type": "module",
+  "exports": {
+    ".": {
+      "require": {
+        "types": "./lib/cjs/index.d.ts",
+        "default": "./lib/cjs/index.js"
+      },
+      "import": {
+        "types": "./lib/esm/index.d.ts",
+        "default": "./lib/esm/index.js"
+      }
+    },
+    "./middleware": {
+      "import": "./lib/esm/middleware/middy.js",
+      "require": "./lib/cjs/middleware/middy.js"
+    },
+    "./types": {
+      "import": "./lib/esm/types/index.js",
+      "require": "./lib/cjs/types/index.js"
+    }
+  },
+  "typesVersions": {
+    "*": {
+      "middleware": [
+        "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/index.d.ts",
+  "main": "./lib/cjs/index.js",
   "devDependencies": {
     "@aws-lambda-powertools/testing-utils": "file:../testing",
     "@types/lodash.merge": "^4.6.7"
@@ -64,4 +100,4 @@
     "serverless",
     "nodejs"
   ]
-}
+}

packages/logger/src/Logger.ts

@@ -2,26 +2,29 @@ import { randomInt } from 'node:crypto';
 import { Console } from 'node:console';
 import type { Context, Handler } from 'aws-lambda';
 import { Utility } from '@aws-lambda-powertools/commons';
-import { LogFormatterInterface, PowertoolsLogFormatter } from './formatter';
-import { LogItem } from './log';
+import { PowertoolsLogFormatter } from './formatter/PowertoolsLogFormatter.js';
+import { LogFormatterInterface } from './formatter/LogFormatterInterface.js';
+import { LogItem } from './log/LogItem.js';
 import merge from 'lodash.merge';
-import { ConfigServiceInterface, EnvironmentVariablesService } from './config';
-import { LogJsonIndent } from './types';
+import { ConfigServiceInterface } from './config/ConfigServiceInterface.js';
+import { EnvironmentVariablesService } from './config/EnvironmentVariablesService.js';
+import { LogJsonIndent } from './types/Logger.js';
 import type {
-  ClassThatLogs,
   Environment,
+  LogAttributes,
+  LogLevel,
+  LogLevelThresholds,
+} from './types/Log.js';
+import type {
+  ClassThatLogs,
   HandlerMethodDecorator,
   LambdaFunctionContext,
-  LogAttributes,
   ConstructorOptions,
   LogItemExtraInput,
   LogItemMessage,
-  LogLevel,
-  LogLevelThresholds,
   PowertoolLogData,
   HandlerOptions,
-} from './types';
-
+} from './types/Logger.js';
 /**
  * ## Intro
  * The Logger utility provides an opinionated logger with output structured as JSON.

packages/logger/src/config/EnvironmentVariablesService.ts

@@ -1,4 +1,4 @@
-import { ConfigServiceInterface } from './ConfigServiceInterface';
+import { ConfigServiceInterface } from './ConfigServiceInterface.js';
 import { EnvironmentVariablesService as CommonEnvironmentVariablesService } from '@aws-lambda-powertools/commons';
 
 /**

packages/logger/src/formatter/LogFormatter.ts

@@ -1,6 +1,7 @@
-import { LogFormatterInterface } from '.';
-import { LogAttributes, UnformattedAttributes } from '../types';
-import { LogItem } from '../log';
+import { LogFormatterInterface } from './LogFormatterInterface.js';
+import { LogAttributes } from '../types/Log.js';
+import { UnformattedAttributes } from '../types/Logger.js';
+import { LogItem } from '../log/LogItem.js';
 
 /**
  * Typeguard to monkey patch Error to add a cause property.