refactor(parameters): replace EnvironmentVariablesService class with helper functions in Parameters (#4168)

Co-authored-by: Stefano Vozza <svozza@amazon.com>

Author: JonkaSusaki

packages/parameters/src/appconfig/AppConfigProvider.ts

@@ -1,3 +1,4 @@
+import { getServiceName } from '@aws-lambda-powertools/commons/utils/env';
 import type { StartConfigurationSessionCommandInput } from '@aws-sdk/client-appconfigdata';
 import {
   AppConfigDataClient,
@@ -206,7 +207,7 @@ class AppConfigProvider extends BaseProvider {
     });
 
     const { application, environment } = options;
-    this.application = application ?? this.envVarsService.getServiceName();
+    this.application = application ?? getServiceName();
     if (!this.application || this.application.trim().length === 0) {
       throw new Error(
         'Application name is not defined or POWERTOOLS_SERVICE_NAME is not set'

packages/parameters/src/base/BaseProvider.ts

@@ -5,7 +5,6 @@ import {
   isSdkClient,
   isString,
 } from '@aws-lambda-powertools/commons';
-import { EnvironmentVariablesService } from '../config/EnvironmentVariablesService.js';
 import { GetParameterError, TransformParameterError } from '../errors.js';
 import type {
   BaseProviderConstructorOptions,
@@ -38,7 +37,6 @@ import { transformValue } from './transformValue.js';
  * this should be an acceptable tradeoff.
  */
 abstract class BaseProvider implements BaseProviderInterface {
-  public envVarsService: EnvironmentVariablesService;
   protected client: unknown;
   protected store: Map<string, ExpirableValue>;
 
@@ -48,7 +46,6 @@ abstract class BaseProvider implements BaseProviderInterface {
     awsSdkV3ClientPrototype,
   }: BaseProviderConstructorOptions) {
     this.store = new Map();
-    this.envVarsService = new EnvironmentVariablesService();
     if (awsSdkV3Client) {
       if (!isSdkClient(awsSdkV3Client) && awsSdkV3ClientPrototype) {
         console.warn(
@@ -96,7 +93,7 @@ abstract class BaseProvider implements BaseProviderInterface {
     name: string,
     options?: GetOptionsInterface
   ): Promise<unknown | undefined> {
-    const configs = new GetOptions(this.envVarsService, options);
+    const configs = new GetOptions(options);
     const key = [name, configs.transform].toString();
 
     if (!configs.forceFetch && !this.hasKeyExpiredInCache(key)) {
@@ -135,7 +132,7 @@ abstract class BaseProvider implements BaseProviderInterface {
     path: string,
     options?: GetMultipleOptionsInterface
   ): Promise<unknown> {
-    const configs = new GetMultipleOptions(this.envVarsService, options);
+    const configs = new GetMultipleOptions(options);
     const key = [path, configs.transform].toString();
 
     if (!configs.forceFetch && !this.hasKeyExpiredInCache(key)) {

packages/parameters/src/base/GetMultipleOptions.ts

@@ -1,4 +1,3 @@
-import type { EnvironmentVariablesService } from '../config/EnvironmentVariablesService.js';
 import type { GetMultipleOptionsInterface } from '../types/BaseProvider.js';
 import { GetOptions } from './GetOptions.js';
 
@@ -13,11 +12,8 @@ class GetMultipleOptions
 {
   public throwOnTransformError = false;
 
-  public constructor(
-    envVarsService: EnvironmentVariablesService,
-    options: GetMultipleOptionsInterface = {}
-  ) {
-    super(envVarsService, options);
+  public constructor(options: GetMultipleOptionsInterface = {}) {
+    super(options);
 
     if (options.throwOnTransformError !== undefined) {
       this.throwOnTransformError = options.throwOnTransformError;

packages/parameters/src/base/GetOptions.ts

@@ -1,4 +1,4 @@
-import type { EnvironmentVariablesService } from '../config/EnvironmentVariablesService.js';
+import { getNumberFromEnv } from '@aws-lambda-powertools/commons/utils/env';
 import { DEFAULT_MAX_AGE_SECS } from '../constants.js';
 import type {
   GetOptionsInterface,
@@ -16,15 +16,14 @@ class GetOptions implements GetOptionsInterface {
   public sdkOptions?: unknown;
   public transform?: TransformOptions;
 
-  public constructor(
-    envVarsService: EnvironmentVariablesService,
-    options: GetOptionsInterface = {}
-  ) {
+  public constructor(options: GetOptionsInterface = {}) {
     Object.assign(this, options);
 
     if (options.maxAge === undefined) {
-      this.maxAge =
-        envVarsService.getParametersMaxAge() ?? DEFAULT_MAX_AGE_SECS;
+      this.maxAge = getNumberFromEnv({
+        key: 'POWERTOOLS_PARAMETERS_MAX_AGE',
+        defaultValue: DEFAULT_MAX_AGE_SECS,
+      });
     }
   }
 }

packages/parameters/src/config/EnvironmentVariablesService.ts

@@ -1,4 +1,5 @@
 import type { JSONValue } from '@aws-lambda-powertools/commons/types';
+import { getBooleanFromEnv } from '@aws-lambda-powertools/commons/utils/env';
 import type {
   GetParameterCommandInput,
   GetParametersByPathCommandInput,
@@ -843,13 +844,12 @@ class SSMProvider extends BaseProvider {
     if (options?.decrypt !== undefined) return options.decrypt;
     if (sdkOptions?.WithDecryption !== undefined)
       return sdkOptions.WithDecryption;
-    if (this.envVarsService.getSSMDecrypt() !== '') {
-      return this.envVarsService.isValueTrue(
-        this.envVarsService.getSSMDecrypt()
-      );
-    }
 
-    return undefined;
+    return getBooleanFromEnv({
+      key: 'POWERTOOLS_PARAMETERS_SSM_DECRYPT',
+      defaultValue: false,
+      extendedParsing: true,
+    });
   }
 
   /**

packages/parameters/src/ssm/SSMProvider.ts

@@ -7,7 +7,6 @@ import {
   GetMultipleOptions,
   GetOptions,
 } from '../../src/base/index.js';
-import type { EnvironmentVariablesService } from '../../src/config/EnvironmentVariablesService.js';
 import { DEFAULT_MAX_AGE_SECS } from '../../src/constants.js';
 import {
   clearCaches,
@@ -550,9 +549,7 @@ describe('Class: GetOptions', () => {
     const envVarsService = {
       getParametersMaxAge: vi.fn(),
     };
-    const options = new GetOptions(
-      envVarsService as unknown as EnvironmentVariablesService
-    );
+    const options = new GetOptions();
 
     // Assess
     expect(options.maxAge).toBe(DEFAULT_MAX_AGE_SECS);
@@ -565,9 +562,7 @@ describe('Class: GetMultipleOptions', () => {
     const envVarsService = {
       getParametersMaxAge: vi.fn(),
     };
-    const options = new GetMultipleOptions(
-      envVarsService as unknown as EnvironmentVariablesService
-    );
+    const options = new GetMultipleOptions();
 
     // Assess
     expect(options.throwOnTransformError).toBe(false);