feat(logger): introduce loglevel constant (#2787)

Author: marlapativ

Diff for: packages/logger/src/constants.ts

@@ -14,4 +14,13 @@ const LogJsonIndent = {
   COMPACT: 0,
 } as const;
 
-export { LogJsonIndent };
+const LogLevel = {
+  DEBUG: 'DEBUG',
+  INFO: 'INFO',
+  WARN: 'WARN',
+  ERROR: 'ERROR',
+  SILENT: 'SILENT',
+  CRITICAL: 'CRITICAL',
+} as const;
+
+export { LogJsonIndent, LogLevel };

Diff for: packages/logger/src/index.ts

@@ -1,3 +1,4 @@
 export { Logger } from './Logger.js';
 export { LogFormatter } from './formatter/LogFormatter.js';
 export { LogItem } from './formatter/LogItem.js';
+export { LogLevel } from './constants.js';

Diff for: packages/logger/src/types/Log.ts

@@ -1,27 +1,11 @@
 import type { EnvironmentVariablesService } from '../config/EnvironmentVariablesService.js';
 import type { LogItem } from '../formatter/LogItem.js';
 import type { UnformattedAttributes } from './Logger.js';
-
-type LogLevelDebug = 'DEBUG';
-type LogLevelInfo = 'INFO';
-type LogLevelWarn = 'WARN';
-type LogLevelError = 'ERROR';
-type LogLevelSilent = 'SILENT';
-type LogLevelCritical = 'CRITICAL';
+import { LogLevel } from '../constants.js';
 
 type LogLevel =
-  | LogLevelDebug
-  | Lowercase<LogLevelDebug>
-  | LogLevelInfo
-  | Lowercase<LogLevelInfo>
-  | LogLevelWarn
-  | Lowercase<LogLevelWarn>
-  | LogLevelError
-  | Lowercase<LogLevelError>
-  | LogLevelSilent
-  | Lowercase<LogLevelSilent>
-  | LogLevelCritical
-  | Lowercase<LogLevelCritical>;
+  | (typeof LogLevel)[keyof typeof LogLevel]
+  | Lowercase<(typeof LogLevel)[keyof typeof LogLevel]>;
 
 type LogLevelThresholds = {
   [key in Uppercase<LogLevel>]: number;

Diff for: packages/logger/tests/unit/Logger.test.ts

@@ -5,11 +5,14 @@
  */
 import context from '@aws-lambda-powertools/testing-utils/context';
 import type { LambdaInterface } from '@aws-lambda-powertools/commons/types';
-import { Logger, LogFormatter } from '../../src/index.js';
+import { Logger, LogFormatter, LogLevel } from '../../src/index.js';
 import { ConfigServiceInterface } from '../../src/types/ConfigServiceInterface.js';
 import { EnvironmentVariablesService } from '../../src/config/EnvironmentVariablesService.js';
 import { PowertoolsLogFormatter } from '../../src/formatter/PowertoolsLogFormatter.js';
-import { LogLevelThresholds, LogLevel } from '../../src/types/Log.js';
+import {
+  LogLevelThresholds,
+  type LogLevel as LogLevelType,
+} from '../../src/types/Log.js';
 import {
   type LogFunction,
   type ConstructorOptions,
@@ -598,7 +601,7 @@ describe('Class: Logger', () => {
         test(`when the level is DEBUG, it ${debugAction} print to stdout`, () => {
           // Prepare
           const logger = new Logger({
-            logLevel: 'DEBUG',
+            logLevel: LogLevel.DEBUG,
           });
           const consoleSpy = jest.spyOn(
             logger['console'],
@@ -656,7 +659,7 @@ describe('Class: Logger', () => {
         test(`when the log level is WARN, it ${warnAction} print to stdout`, () => {
           // Prepare
           const logger = new Logger({
-            logLevel: 'WARN',
+            logLevel: LogLevel.WARN,
           });
           const consoleSpy = jest.spyOn(
             logger['console'],
@@ -714,7 +717,7 @@ describe('Class: Logger', () => {
         test('when the log level is SILENT, it DOES NOT print to stdout', () => {
           // Prepare
           const logger = new Logger({
-            logLevel: 'SILENT',
+            logLevel: LogLevel.SILENT,
           });
           const consoleSpy = jest.spyOn(
             logger['console'],
@@ -2347,7 +2350,7 @@ describe('Class: Logger', () => {
     test('when logEvent is enabled, it logs the event in the first log', async () => {
       // Prepare
       const logger = new Logger({
-        logLevel: 'DEBUG',
+        logLevel: LogLevel.DEBUG,
       });
       const consoleSpy = jest.spyOn(logger['console'], 'info');
       class LambdaFunction implements LambdaInterface {
@@ -3141,7 +3144,7 @@ describe('Class: Logger', () => {
       const logger = new Logger();
 
       // Act
-      logger.setLogLevel('ERROR');
+      logger.setLogLevel(LogLevel.ERROR);
 
       // Assess
       expect(logger.level).toBe(20);
@@ -3153,7 +3156,7 @@ describe('Class: Logger', () => {
       const logger = new Logger();
 
       // Act & Assess
-      expect(() => logger.setLogLevel('INVALID' as LogLevel)).toThrow(
+      expect(() => logger.setLogLevel('INVALID' as LogLevelType)).toThrow(
         'Invalid log level: INVALID'
       );
     });
@@ -3240,7 +3243,7 @@ describe('Class: Logger', () => {
       process.env.POWERTOOLS_LOGGER_SAMPLE_RATE = '1';
 
       const logger: Logger = new Logger({
-        logLevel: 'ERROR',
+        logLevel: LogLevel.ERROR,
       });
 
       // Assess
@@ -3396,7 +3399,7 @@ describe('Class: Logger', () => {
     test('when sample rate in constructor is out of expected range, it should be ignored', () => {
       // Prepare
       const logger: Logger = new Logger({
-        logLevel: 'INFO',
+        logLevel: LogLevel.INFO,
         sampleRateValue: 42,
       });
       const consoleSpy = jest.spyOn(logger['console'], 'info');
@@ -3498,7 +3501,7 @@ describe('Class: Logger', () => {
       test('when sample rate calculation is refreshed, it DOES NOT overwrite the sample rate value', () => {
         // Prepare
         const logger = new Logger({
-          logLevel: 'INFO',
+          logLevel: LogLevel.INFO,
           sampleRateValue: 1,
         });
         const consoleSpy = jest.spyOn(logger['console'], 'info');