feat(logger): Support for external observability providers

docs/snippets/logger/bringYourOwnFormatterClass.ts

@@ -3,13 +3,17 @@ import {
   LogAttributes,
   UnformattedAttributes,
 } from '@aws-lambda-powertools/logger/lib/types';
+import { LogItem } from '@aws-lambda-powertools/logger/lib/log';
 
 // Replace this line with your own type
 type MyCompanyLog = LogAttributes;
 
 class MyCompanyLogFormatter extends LogFormatter {
-  public formatAttributes(attributes: UnformattedAttributes): MyCompanyLog {
-    return {
+  public formatAttributes(
+    attributes: UnformattedAttributes,
+    additionalLogAttributes: LogAttributes
+  ): LogItem {
+    const baseAttributes: MyCompanyLog = {
       message: attributes.message,
       service: attributes.serviceName,
       environment: attributes.environment,
@@ -31,6 +35,11 @@ class MyCompanyLogFormatter extends LogFormatter {
         sampleRateValue: attributes.sampleRateValue,
       },
     };
+
+    const logItem = new LogItem({ attributes: baseAttributes });
+    logItem.addAttributes(additionalLogAttributes); // add any attributes not explicitly defined
+
+    return logItem;
   }
 }
 

packages/logger/src/Logger.ts

@@ -2,7 +2,7 @@ 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, PowertoolLogFormatter } from './formatter';
+import { LogFormatterInterface, PowertoolsLogFormatter } from './formatter';
 import { LogItem } from './log';
 import merge from 'lodash.merge';
 import { ConfigServiceInterface, EnvironmentVariablesService } from './config';
@@ -617,16 +617,13 @@ class Logger extends Utility implements ClassThatLogs {
       this.getPowertoolLogData()
     );
 
-    const logItem = new LogItem({
-      baseAttributes: this.getLogFormatter().formatAttributes(
-        unformattedBaseAttributes
-      ),
-      persistentAttributes: this.getPersistentLogAttributes(),
-    });
-
-    // Add ephemeral attributes
+    let additionalLogAttributes: LogAttributes = {};
+    additionalLogAttributes = merge(
+      additionalLogAttributes,
+      this.getPersistentLogAttributes()
+    );
     if (typeof input !== 'string') {
-      logItem.addAttributes(input);
+      additionalLogAttributes = merge(additionalLogAttributes, input);
     }
     extraInput.forEach((item: Error | LogAttributes | string) => {
       const attributes: LogAttributes =
@@ -636,9 +633,14 @@ class Logger extends Utility implements ClassThatLogs {
           ? { extra: item }
           : item;
 
-      logItem.addAttributes(attributes);
+      additionalLogAttributes = merge(additionalLogAttributes, attributes);
     });
 
+    const logItem = this.getLogFormatter().formatAttributes(
+      unformattedBaseAttributes,
+      additionalLogAttributes
+    );
+
     return logItem;
   }
 
@@ -915,7 +917,7 @@ class Logger extends Utility implements ClassThatLogs {
    * @returns {void}
    */
   private setLogFormatter(logFormatter?: LogFormatterInterface): void {
-    this.logFormatter = logFormatter || new PowertoolLogFormatter();
+    this.logFormatter = logFormatter || new PowertoolsLogFormatter();
   }
 
   /**

packages/logger/src/formatter/LogFormatter.ts

@@ -1,5 +1,6 @@
 import { LogFormatterInterface } from '.';
 import { LogAttributes, UnformattedAttributes } from '../types';
+import { LogItem } from '../log';
 
 /**
  * This class defines and implements common methods for the formatting of log attributes.
@@ -13,11 +14,13 @@ abstract class LogFormatter implements LogFormatterInterface {
    * It formats key-value pairs of log attributes.
    *
    * @param {UnformattedAttributes} attributes
-   * @returns {LogAttributes}
+   * @param {LogAttributes} additionalLogAttributes
+   * @returns {LogItem}
    */
   public abstract formatAttributes(
-    attributes: UnformattedAttributes
-  ): LogAttributes;
+    attributes: UnformattedAttributes,
+    additionalLogAttributes: LogAttributes
+  ): LogItem;
 
   /**
    * It formats a given Error parameter.

packages/logger/src/formatter/LogFormatterInterface.ts

@@ -1,4 +1,5 @@
 import { LogAttributes, UnformattedAttributes } from '../types';
+import { LogItem } from '../log';
 
 /**
  * @interface
@@ -8,9 +9,13 @@ interface LogFormatterInterface {
    * It formats key-value pairs of log attributes.
    *
    * @param {UnformattedAttributes} attributes
-   * @returns {PowertoolLog}
+   * @param {LogAttributes} additionalLogAttributes
+   * @returns {LogItem}
    */
-  formatAttributes(attributes: UnformattedAttributes): LogAttributes;
+  formatAttributes(
+    attributes: UnformattedAttributes,
+    additionalLogAttributes: LogAttributes
+  ): LogItem;
 
   /**
    * It formats a given Error parameter.

packages/logger/src/formatter/PowertoolLogFormatter.ts → packages/logger/src/formatter/PowertoolsLogFormatter.ts

@@ -1,6 +1,7 @@
 import { LogFormatter } from '.';
-import { UnformattedAttributes } from '../types';
-import { PowertoolLog } from '../types/formats';
+import { LogAttributes, UnformattedAttributes } from '../types';
+import { PowertoolsLog } from '../types/formats';
+import { LogItem } from '../log';
 
 /**
  * This class is used to transform a set of log key-value pairs
@@ -9,15 +10,19 @@ import { PowertoolLog } from '../types/formats';
  * @class
  * @extends {LogFormatter}
  */
-class PowertoolLogFormatter extends LogFormatter {
+class PowertoolsLogFormatter extends LogFormatter {
   /**
    * It formats key-value pairs of log attributes.
    *
    * @param {UnformattedAttributes} attributes
-   * @returns {PowertoolLog}
+   * @param {LogAttributes} additionalLogAttributes
+   * @returns {PowertoolsLog}
    */
-  public formatAttributes(attributes: UnformattedAttributes): PowertoolLog {
-    return {
+  public formatAttributes(
+    attributes: UnformattedAttributes,
+    additionalLogAttributes: LogAttributes
+  ): LogItem {
+    const baseAttributes: PowertoolsLog = {
       cold_start: attributes.lambdaContext?.coldStart,
       function_arn: attributes.lambdaContext?.invokedFunctionArn,
       function_memory_size: attributes.lambdaContext?.memoryLimitInMB,
@@ -30,7 +35,13 @@ class PowertoolLogFormatter extends LogFormatter {
       timestamp: this.formatTimestamp(attributes.timestamp),
       xray_trace_id: attributes.xRayTraceId,
     };
+
+    const powertoolLogItem = new LogItem({ attributes: baseAttributes });
+
+    powertoolLogItem.addAttributes(additionalLogAttributes);
+
+    return powertoolLogItem;
   }
 }
 
-export { PowertoolLogFormatter };
+export { PowertoolsLogFormatter };

packages/logger/src/formatter/index.ts

@@ -1,3 +1,3 @@
 export * from './LogFormatter';
 export * from './LogFormatterInterface';
-export * from './PowertoolLogFormatter';
+export * from './PowertoolsLogFormatter';

packages/logger/src/log/LogItem.ts

@@ -5,16 +5,12 @@ import { LogAttributes } from '../types';
 class LogItem implements LogItemInterface {
   private attributes: LogAttributes = {};
 
-  public constructor(params: {
-    baseAttributes: LogAttributes;
-    persistentAttributes: LogAttributes;
-  }) {
+  public constructor(params: { attributes: LogAttributes }) {
     // Add attributes in the log item in this order:
     // - Base attributes supported by the Powertool by default
-    // - Persistent attributes provided by developer, not formatted
+    // - Persistent attributes provided by developer, not formatted (done later)
     // - Ephemeral attributes provided as parameters for a single log item (done later)
-    this.addAttributes(params.baseAttributes);
-    this.addAttributes(params.persistentAttributes);
+    this.addAttributes(params.attributes);
   }
 
   public addAttributes(attributes: LogAttributes): LogItem {

packages/logger/src/types/formats/PowertoolLog.ts → packages/logger/src/types/formats/PowertoolsLog.ts

@@ -1,6 +1,6 @@
 import type { LogAttributes, LogLevel } from '..';
 
-type PowertoolLog = LogAttributes & {
+type PowertoolsLog = LogAttributes & {
   /**
    * timestamp
    *
@@ -90,4 +90,4 @@ type PowertoolLog = LogAttributes & {
   lambda_request_id?: string;
 };
 
-export type { PowertoolLog };
+export type { PowertoolsLog };

packages/logger/src/types/formats/index.ts

@@ -1 +1 @@
-export * from './PowertoolLog';
+export * from './PowertoolsLog';

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

@@ -10,7 +10,7 @@ import {
 } from '@aws-lambda-powertools/commons';
 import { createLogger, Logger } from '../../src';
 import { EnvironmentVariablesService } from '../../src/config';
-import { PowertoolLogFormatter } from '../../src/formatter';
+import { PowertoolsLogFormatter } from '../../src/formatter';
 import {
   ClassThatLogs,
   LogJsonIndent,
@@ -798,7 +798,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: 0,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1621,7 +1621,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1644,7 +1644,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1667,7 +1667,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1733,7 +1733,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1756,7 +1756,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1782,7 +1782,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1805,7 +1805,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 20,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1849,7 +1849,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1872,7 +1872,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1902,7 +1902,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: INDENTATION,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1943,7 +1943,7 @@ describe('Class: Logger', () => {
         envVarsService: expect.any(EnvironmentVariablesService),
         logEvent: false,
         logIndentation: 0,
-        logFormatter: expect.any(PowertoolLogFormatter),
+        logFormatter: expect.any(PowertoolsLogFormatter),
         logLevel: 8,
         logLevelThresholds: {
           ...logLevelThresholds,
@@ -1970,7 +1970,7 @@ describe('Class: Logger', () => {
 
     test('child logger should have the same logFormatter as its parent', () => {
       // Prepare
-      class MyCustomLogFormatter extends PowertoolLogFormatter {}
+      class MyCustomLogFormatter extends PowertoolsLogFormatter {}
       const parentLogger = new Logger({
         logFormatter: new MyCustomLogFormatter(),
       });
@@ -1988,7 +1988,7 @@ describe('Class: Logger', () => {
 
     test('child logger with custom logFormatter in options should have provided logFormatter', () => {
       // Prepare
-      class MyCustomLogFormatter extends PowertoolLogFormatter {}
+      class MyCustomLogFormatter extends PowertoolsLogFormatter {}
       const parentLogger = new Logger();
 
       // Act
@@ -1999,7 +1999,7 @@ describe('Class: Logger', () => {
       // Assess
       expect(parentLogger).toEqual(
         expect.objectContaining({
-          logFormatter: expect.any(PowertoolLogFormatter),
+          logFormatter: expect.any(PowertoolsLogFormatter),
         })
       );
 
@@ -2012,7 +2012,7 @@ describe('Class: Logger', () => {
 
     test('child logger should have exact same attributes as the parent logger created with all non-default options', () => {
       // Prepare
-      class MyCustomLogFormatter extends PowertoolLogFormatter {}
+      class MyCustomLogFormatter extends PowertoolsLogFormatter {}
       class MyCustomEnvironmentVariablesService extends EnvironmentVariablesService {}
 
       const options: ConstructorOptions = {