build(logger): reduce node_modules size

package.json

@@ -45,7 +45,6 @@
   "devDependencies": {
     "@types/aws-lambda": "^8.10.72",
     "@types/jest": "^27.0.0",
-    "@types/lodash": "^4.14.168",
     "@types/node": "^17.0.0",
     "@typescript-eslint/eslint-plugin": "^5.5.0",
     "@typescript-eslint/parser": "^5.5.0",

packages/logger/package.json

@@ -42,7 +42,9 @@
   "typedocMain": "src/index.ts",
   "devDependencies": {
     "@types/jest": "^27.0.0",
-    "@types/lodash": "^4.14.168",
+    "@types/lodash.clonedeep": "^4.5.6",
+    "@types/lodash.merge": "^4.6.6",
+    "@types/lodash.pickby": "^4.6.6",
     "@types/node": "^16.0.0",
     "@typescript-eslint/eslint-plugin": "^5.4.0",
     "@typescript-eslint/parser": "^5.4.0",
@@ -69,8 +71,8 @@
     "@aws-lambda-powertools/commons": "0.2.0",
     "@middy/core": "^2.5.3",
     "@types/aws-lambda": "^8.10.72",
-    "lodash": "^4.17.21",
     "lodash.clonedeep": "^4.5.0",
-    "lodash.merge": "^4.6.2"
+    "lodash.merge": "^4.6.2",
+    "lodash.pickby": "^4.6.0"
   }
-}
+}

packages/logger/src/Logger.ts

@@ -1,7 +1,8 @@
 import type { Context } from 'aws-lambda';
 import { LogFormatterInterface, PowertoolLogFormatter } from './formatter';
 import { LogItem } from './log';
-import { cloneDeep, merge } from 'lodash/fp';
+import cloneDeep from 'lodash.clonedeep';
+import merge from 'lodash.merge';
 import { ConfigServiceInterface, EnvironmentVariablesService } from './config';
 import type {
   Environment,
@@ -69,7 +70,7 @@ class Logger implements ClassThatLogs {
   }
 
   public addPersistentLogAttributes(attributes?: LogAttributes): void {
-    this.persistentLogAttributes = merge(this.getPersistentLogAttributes(), attributes);
+    this.persistentLogAttributes = merge(attributes, this.getPersistentLogAttributes());
   }
 
   public appendKeys(attributes?: LogAttributes): void {
@@ -148,16 +149,16 @@ class Logger implements ClassThatLogs {
 
   private addToPowertoolLogData(...attributesArray: Array<Partial<PowertoolLogData>>): void {
     attributesArray.forEach((attributes: Partial<PowertoolLogData>) => {
-      this.powertoolLogData = merge(this.getPowertoolLogData(), attributes);
+      this.powertoolLogData = merge(attributes, this.getPowertoolLogData());
     });
   }
 
   private createAndPopulateLogItem(logLevel: LogLevel, input: LogItemMessage, extraInput: LogItemExtraInput): LogItem {
-    const unformattedBaseAttributes = merge(this.getPowertoolLogData(), {
+    const unformattedBaseAttributes = merge({
       logLevel,
       timestamp: new Date(),
       message: typeof input === 'string' ? input : input.message,
-    });
+    }, this.getPowertoolLogData());
 
     const logItem = new LogItem({
       baseAttributes: this.getLogFormatter().formatAttributes(unformattedBaseAttributes),

packages/logger/src/log/LogItem.ts

@@ -1,4 +1,5 @@
-import { pickBy, merge } from 'lodash';
+import pickBy from 'lodash.pickby';
+import merge from 'lodash.merge';
 import { LogItemInterface } from '.';
 import { LogAttributes } from '../types';
 

packages/logger/tests/unit/Logger.test.ts

@@ -650,6 +650,8 @@ describe('Class: Logger', () => {
       class LambdaFunction implements LambdaInterface {
 
         @logger.injectLambdaContext()
+        // eslint-disable-next-line @typescript-eslint/ban-ts-comment
+        // @ts-ignore
         public async handler<TEvent>(_event: TEvent, _context: Context): Promise<string> {
           logger.info('This is an INFO log with some context');